Interview Questions

1. What is a Hypervisor?
It is a program that allows multiple operating systems to share a single hardware host. Each operating system appears to have the host's processor, memory, and other resources all to itself. However, the hypervisor is actually controlling the host processor and resources, allocating what is needed to each operating system in turn and making sure that the guest operating systems (called virtual machines) cannot disrupt each other.

2. What is the hardware version used in VMware ESXi 5.5?
Version 10

Below is the table showing the different version of hardware used in different VMware products along with their release version
Virtual Hardware Version
Products
10
ESXi 5.5, Fusion 6.x, Workstation 10.x, Player 6.x
9
ESXi 5.1, Fusion 5.x, Workstation 9.x, Player 5.x
8
ESXi 5.0, Fusion 4.x, Workstation 8.x, Player 4.x
7
ESXi/ESX 4.x, Fusion 2.x/3.x Workstation 6.5.x/7.x,Player 3.x
6
Workstation 6.0.x
4
ACE 2.x, ESX 3.x, Fusion 1.x, Player 2.x
3 and 4
ACE 1.x, Player 1.x, Server 1.x, Workstation 5.x, Workstation 4.x
3
ESX 2.x, GSX Server 3.x

3. What is the difference between the vSphere ESX and ESXi architectures?
VMware ESX and ESXi are both bare metal hypervisor architectures that install directly on the server hardware.
Although neither hypervisor architectures relies on an OS for resource management, the vSphere ESX architecture relied on a Linux operating system, called the Console OS (COS) or service console, to perform two management functions: executing scripts and installing third-party agents for hardware monitoring, backup or systems management.
In the vSphere ESXi architecture, the service console has been removed. The smaller code base of vSphere ESXi represents a smaller “attack surface” and less code to patch, improving reliability and security.

For Complete Differences: http://thecloudwiki.blogspot.in/2014/11/vmware-esxi-server-compare-to-esx-server.html

4. What is a .vmdk file?
This isn't the file containing the raw data. Instead it is the disk descriptor file which describes the size and geometry of the virtual disk file. This file is in text format and contains the name of the –flat.vmdk file for which it is associated with and also the hard drive adapter type, drive sectors, heads and cylinders, etc. One of these files will exist for each virtual hard drive that is assigned to your virtual machine. You can tell which –flat.vmdk file it is associated with by opening the file and looking at the Extent Description field.

Follow the below link for more details

5. What are the different types of virtualization?
Server Virtualization – consolidating multiple physical servers into virtual servers that run on a single physical server.

Application Virtualization – an application runs on another host from where it is installed in a variety of ways. It could be done by application streaming, desktop virtualization or VDI, or a VM package (like VMware ACE creates with a player). Microsoft Softgrid is an example of Application virtualization.

Presentation Virtualization – This is what Citrix Met frame (and the ICA protocol) as well as Microsoft Terminal Services (and RDP) are able to create. With presentation virtualization, an application actually runs on another host and all that you see on the client is the screen from where it is run.

Network Virtualization – with network virtualization, the network is “carved up” and can be used for multiple purposes such as running a protocol analyzer inside an Ethernet switch. Components of a virtual network could include NICs, switches, VLANs, network storage devices, virtual network containers, and network media.

Storage Virtualization – with storage virtualization, the disk/data storage for your data is consolidated to and managed by a virtual storage system. The servers connected to the storage system aren’t aware of where the data really is. Storage virtualization is sometimes described as “abstracting the logical storage from the physical storage.

6. What is VMware vMotion and what are its requirements?
VMware VMotion enables the live migration of running virtual machines from one physical server to another with zero downtime.

VMotion lets you:
  • Automatically optimize and allocate entire pools of resources for maximum hardware utilization and
  • availability.
  • Perform hardware maintenance without any scheduled downtime.
  • Proactively migrate virtual machines away from failing or under performing servers.
Below are the pre-requisites for configuring vMotion
  • Each host must be correctly licensed for vMotion
  • Each host must meet shared storage requirements
    • vMotion migrates the vm from one host to another which is only possible with both the host are sharing a common storage or to any storage accessible by both the source and target hosts. 
    • A shared storage can be on a Fibre Channel storage area network (SAN), or can be implemented using iSCSI SAN and NAS.
    • If you use vMotion to migrate virtual machines with raw device mapping (RDM) files, make sure to maintain consistent LUN IDs for RDMs across all participating hosts.
  • Each host must meet the networking requirements
    • Configure a VMkernel port on each host.
    • Dedicate at least one GigE adapter for vMotion.
    • Use at least one 10 GigE adapter if you migrate workloads that have many memory operations.
    • Use jumbo frames for best vMotion performance.
    • Ensure that jumbo frames are enabled on all network devices that are on the vMotion path including physical NICs, physical switches and virtual switches.

7. What is the difference between clone and template in VMware?
Clone
  • A clone is a copy of virtual machine.
  • You cannot convert back the cloned Virtual Machine.
  • A Clone of a Virtual Machine can be created when the Virtual Machine is powered on
  • Cloning can be done in two ways namely Full Clone and Linked Clone.
  • A full clone is an independent copy of a virtual machine that shares nothing with the parent virtual machine after the cloning operation. Ongoing operation of a full clone is entirely separate from the parent virtual machine.
  • A linked clone is a copy of a virtual machine that shares virtual disks with the parent virtual machine in an ongoing manner. This conserves disk space, and allows multiple virtual machines to use the same software installation.
  • Cloning a virtual machine can save time if you are deploying many similar virtual machines. You can create, configure, and install software on a single virtual machine, and then clone it multiple times, rather than creating and configuring each virtual machine individually.

Template
  • A template is a master copy or a baseline image of a virtual machine that can be used to create many clones.
  • Templates cannot be powered on or edited, and are more difficult to alter than ordinary virtual machine.
  • You can convert the template back to Virtual Machine to update the base template with the latest released patches and updates and to install or upgrade any software and again convert back to template to be used for future deployment of Virtual Machines with the latest patches.
  • Convert virtual Machine to template cannot be performed, when Virtual machine is powered on.  Only Clone to Template can be performed when the Virtual Machine is powered on.
  • A template offers a more secure way of preserving a virtual machine configuration that you want to deploy many times.
  • When you clone a virtual machine or deploy a virtual machine from a template, the resulting cloned virtual machine is independent of the original virtual machine or template.

8. What is promiscuous mode in Vmware?
  • Promiscuous mode is a security policy which can be defined at the virtual switch or portgroup level
  • A virtual machine, Service Console or VMkernel network interface in a portgroup which allows use of promiscuous mode can see all network traffic traversing the virtual switch.
  • If this mode is set to reject, the packets are sent to intended port so that the intended virtual machine will only be able to see the communication.
  • Example: In case you are using a virtual xp inside any Windows VM. If promiscuous mode is set to reject then the virtual xp won't be able to connect the network unless promiscuous mode is enabled for the Windows VM.

9. What is the difference between Thick provision Lazy Zeroed, Thick provision Eager Zeroed and Thin provision?
Thick Provision Lazy Zeroed
  • Creates a virtual disk in a default thick format.
  • Space required for the virtual disk is allocated when the virtual disk is created.
  • Data remaining on the physical device is not erased during creation, but is zeroed out on demand at a later time on first write from the virtual machine.
  • Using the default flat virtual disk format does not zero out or eliminate the possibility of recovering deleted files or restoring old data that might be present on this allocated space.
  • You cannot convert a flat disk to a thin disk.

Thick Provision Eager Zeroed
  • A type of thick virtual disk that supports clustering features such as Fault Tolerance.
  • Space required for the virtual disk is allocated at creation time.
  • In contrast to the flat format, the data remaining on the physical device is zeroed out when the virtual disk is created.
  • It might take much longer to create disks in this format than to create other types of disks.

Thin Provision
  • It provides on on-demand allocation of blocks of data.
  • All the space allocated at the time of creation of virtual disk is not utilized on the hard disk, rather only the size with utilized data is locked and the size increases as the amount of data is increased on the disk.
  • With thin provisioning, storage capacity utilization efficiency can be automatically driven up towards 100% with very little administrative overhead.

10. What is a snapshot?
A snapshot is a “point in time image” of a virtual guest operating system (VM). That snapshot contains an image of the VMs disk, RAM, and devices at the time the snapshot was taken. With the snapshot, you can return the VM to that point in time, whenever you choose. You can take snapshots of your VMs, no matter what guest OS you have and the snapshot functionality can be used for features like performing image level backups of the VMs without ever shutting them down.

11. What is VDI?
  • VDI stands for Virtual Desktop Infrastructure where end user physical machine like desktop or laptop are virtualized due to which VMware described VDI as "delivering desktops from the data center”.
  • Once VDI is used the end user connect to their desktop using a device called thin client.
  • The end user can also connect to their desktop using VMware Horizon View installed on any desktop or mobile devices

12. What is VMware HA?
  • VMware HA i.e. High Availability which works on the host level and is configured on the Cluster.
  • A Cluster configured with HA will migrate and restart all the vms running under any of the host in case of any host-level failure automatically to another host under the same cluster.
  • VMware HA continuously monitors all ESX Server hosts in a cluster and detects failures.
  • VMware HA agent placed on each host maintains a heartbeat with the other hosts in the cluster using the service console network. Each server sends heartbeats to the others servers in the cluster at five-second intervals. If any servers lose heartbeat over three consecutive heartbeat intervals, VMware HA initiates the failover action of restarting all affected virtual machines on other hosts.
  • You can set virtual machine restart priority in case of any host failure depending upon the critical nature of the vm.
NOTE: Using HA in case of any host failure with RESTART the vms on different host so the vms state will be interrupted and it is not a live migration

13. What is the difference between VMware HA and vMotion?
VMware HA is used in the event when any of the hosts inside a cluster fails then all the virtual machines running under it are restarted on different host in the same cluster.
Now HA is completely dependent on vMotion to migrate the vms to different host so vMotion is just used for the migration purpose between multiple hosts. vMotion also has the capability to migrate any vm without interrupting its state to any of the host inside cluster.

14. What is storage vMotion?
  • Storage vMotion is similar to vMotion in the sense that "something" related to the VM is moved and there is no downtime to the VM guest and end users. However, with SVMotion the VM Guest stays on the server that it resides on but the virtual disk for that VM is what moves.
  • With Storage vMotion, you can migrate a virtual machine and its disk files from one datastore to another while the virtual machine is running.
  • You can choose to place the virtual machine and all its disks in a single location, or select separate locations for the virtual machine configuration file and each virtual disk.
  • During a migration with Storage vMotion, you can transform virtual disks from Thick-Provisioned Lazy Zeroed or Thick-Provisioned Eager Zeroed to Thin-Provisioned or the reverse.
  • Perform live migration of virtual machine disk files across any Fibre Channel, iSCSI, FCoE and NFS storage

15. What is VMware DRS and how does it works?
  • Here DRS stands for Distributed Resource Scheduler which dynamically balances resource across various host under Cluster or resource pool.
  • VMware DRS allows users to define the rules and policies that decide how virtual machines share resources and how these resources are prioritized among multiple virtual machines.
  • Resources are allocated to the virtual machine by either migrating it to another server with more available resources or by making more “space” for it on the same server by migrating other virtual machines to different servers.
  • The live migration of virtual machines to different physical servers is executed completely transparent to end-users through VMware VMotion
  • VMware DRS can be configured to operate in either automatic or manual mode. In automatic mode, VMware DRS determines the best possible distribution of virtual machines among different physical servers and automatically migrates virtual machines to the most appropriate physical servers. In manual mode, VMware DRS provides a recommendation for optimal placement of virtual machines, and leaves it to the system administrator to decide whether to make the change.

16. What is VMware Fault Tolerance?
  • VMware Fault Tolerance provides continuous availability to applications running in a virtual machine, preventing downtime and data loss in the event of server failures.
  • VMware Fault Tolerance, when enabled for a virtual machine, creates a live shadow instance of the primary, running on another physical server.
  • The two instances are kept in virtual lockstep with each other using VMware vLockstep technology
  • The two virtual machines play the exact same set of events, because they get the exact same set of inputs at any given time.
  • The two virtual machines constantly heartbeat against each other and if either virtual machine instance loses the heartbeat, the other takes over immediately. The heartbeats are very frequent, with millisecond intervals, making the failover instantaneous with no loss of data or state.
  • VMware Fault Tolerance requires a dedicated network connection, separate from the VMware VMotion network, between the two physical servers.

17. In a cluster with more than 3 hosts, can you tell Fault Tolerance where to put the Fault Tolerance virtual machine or does it chose on its own?
You can place the original (or Primary virtual machine). You have full control with DRS or vMotion to assign it to any node. The placement of the Secondary, when created, is automatic based on the available hosts. But when the Secondary is created and placed, you can vMotion it to the preferred host.

18. How many virtual CPUs can I use on a Fault Tolerant virtual machine ?
vCenter Server 4.x and vCenter Server 5.x support 1 virtual CPU per protected virtual machine.

19. What happens if vCenter Server is offline when a failover event occurs?
When Fault Tolerance is configured for a virtual machine, vCenter Server need not be online for FT to work. Even if vCenter Server is offline, failover still occurs from the Primary to the Secondary virtual machine. Additionally, the spawning of a new Secondary virtual machine also occurs without vCenter Server.

20. What is the difference between Type 1 and Type 2 Hypervisor?
Type 1 Hypervisor
  • This is also known as Bare Metal or Embedded or Native Hypervisor.
  • It works directly on the hardware of the host and can monitor operating systems that run above the hypervisor.
  • It is completely independent from the Operating System.
  • The hypervisor is small as its main task is sharing and managing hardware resources between different operating systems.
  • A major advantage is that any problems in one virtual machine or guest operating system do not affect the other guest operating systems running on the hypervisor.
  • Examples: VMware ESXi Server, Microsoft Hyper-V, Citrix/Xen Server

Type 2 Hypervisor
  • This is also known as Hosted Hypervisor.
  • In this case, the hypervisor is installed on an operating system and then supports other operating systems above it.
  • It is completely dependent on host Operating System for its operations
  • While having a base operating system allows better specification of policies, any problems in the base operating system a ffects the entire system as well even if the hypervisor running above the base OS is secure.
  • Examples: VMware Workstation, Microsoft Virtual PC, Oracle Virtual Box
21. How does vSphere HA works?
When we configure multiple hosts for HA cluster, a single host is automatically elected as the master host. The master host communicates with vCenter Server and monitors the state of all protected virtual machines and of the slave hosts. When you add a host to a vSphere HA cluster, an agent is uploaded to the host and configured to communicate with other agents in the cluster.

22. What are the monitoring methods used for vSphere HA?
The Master and Slave hosts uses two types of monitoring the status of the hosts
  • Datastore Heartbeat
  • Network Heartbeat
23. What are the roles of master host in vSphere HA?
  • Monitoring the state of slave hosts. If a slave host fails or becomes unreachable, the master host identifies which virtual machines need to be restarted.
  • Monitoring the power state of all protected virtual machines. If one virtual machine fails, the master host ensures that it is restarted. Using a local placement engine, the master host also determines where the restart should be done.
  • Managing the lists of cluster hosts and protected virtual machines.
  • Acting as vCenter Server management interface to the cluster and reporting the cluster health state.
24. How is a Master host elected in vSphere HA environment?
When vSphere HA is enabled for a cluster, all active hosts (those not in standby or maintenance mode, or not disconnected) participate in an election to choose the cluster's master host. The host that mounts the greatest number of datastores has an advantage in the election. Only one master host typically exists per cluster and all other hosts are slave hosts.

If the master host fails, is shut down or put in standby mode, or is removed from the cluster a new election is held.

25. If the vCenterserver goes down with a situation that it was pre configured with vSphere HA and DRS, so after power down will HA and DRS perform their task?
vSphere HA is not dependent on vCenterserver for its operations as when HA is configured it installs an agent into each host which does its part and is not dependent on vCenterserver. Also HA doesnot uses vMotion, it justs restarts the vms into another host in any case of host failure.

Further vSphere DRS is very much dependent on vCenterserver as it uses vMotion for its action for live migration of vms between multiple hosts so in case vCenterserver goes down the vMotion won't work leading to failure of DRS.

26. What is the use of vmware tools?
VMware Tools is a suite of utilities that enhances the performance of the virtual machine's guest operating system and improves management of the virtual machine. Without VMware Tools installed in your guest operating system, guest performance lacks important functionality. Installing VMware Tools eliminates or improves these issues:
  • Low video resolution
  • Inadequate color depth
  • Incorrect display of network speed
  • Restricted movement of the mouse
  • Inability to copy and paste and drag-and-drop files
  • Missing sound
  • Provides the ability to take quiesced snapshots of the guest OS
  • Synchronizes the time in the guest operating system with the time on the host
  • Provides support for guest-bound calls created with the VMware VIX API
=============================================================================================
1. VMWare Kernel is a Proprietary Kenral and is not based on any of the UNIX operating systems, it's a kernel developed by VMWare Company. 

2. The VMKernel can't boot it by itself, so that it takes the help of the 3rd party operating system. In VMWare case the kernel is booted by RedHat Linux operating system which is known as service console. 


3. The service console is developed based up on Redhat Linux Operating system, it is used to manage the VMKernel  


4. To restart webaccess service on vmware
service vmware-webaccess restart – this will restart apache tomcat app 


5. To restart ssh service on vmware
service sshd restart 


6. To restart host agent(vmware-hostd) on vmware esx server
service mgmt-vmware restart 


7. Path for the struts-config.xml
/usr/lib/vmware/webAccess/tomcat/apache-tomcat-5.5.17/webapps/ui/WEB-INF/ 


8. To start the scripted install the command is
    esx ks=nfs:111.222.333.444:/data/KS.config ksdevice=eth0
               location                                             device name


9. Virtual Network in Simple……………….

Virtual Nic(s) on Virtual Machine(s) -----> 

Physical Nic on the ESX Server (Virtual Switch - 56 Ports)  ----->

Physical Switch Port Should be trunked with all the VLANS to which the VM's need access  

All the ESX servers should be configured with Same number of Physical Nics (vSwitches) and Connectivity also should be same, So that vMotion succeeds
All the Virtual Machines are connected to one vSwitch with Different VLANS, this means the Physical Nic(vSwitch) needs to be trunked with the same VLANS on the Physical Switch Port



10 What are the three port groups present in ESX server networking
   1. Virtual Machine Port Group - Used for Virtual Machine Network
   2. Service Console Port Group - Used for Service Console Communications
   3. VMKernel Port Group - Used for VMotion, iSCSI, NFS Communications


11. What is the use of a Port Group?
The port group segregates the type of communication.


12. What are the type of communications which requires an IP address for sure ?
   Service Console and VMKernel (VMotion and iSCSI), these communications does not happen without an ip address (Whether it is a single or dedicated)


13. In the ESX Server licensing features VMotion License is showing as Not used, why?
    Even though the license box is selected, it shows as "License Not Used" until, you enable the VMotion option for specific vSwitch

 14. How the Virtual Machineort group communication works ? 
     All the vm's which are configured in VM Port Group are able to connect to the physical machines on the network. So this port group enables communication between vSwitch and Physical Switch to connect vm's to Physical Machine's


15. What is a VLAN ?
     A VLAN is a logical configuration on the switch port to segment the IP Traffic. For this to happen, the port must be trunked with the correct VLAN ID.


16. Does the vSwitches support VLAN Tagging? Why? 
     Yes, The vSwitches support VLAN Tagging, otherwise if the virtual machines in an esx host are connected to different VLANS, we need to install a separate physical nic (vSwitch) for every VLAN. That is the reason vmware included the VLANtagging for vSwitches. So every vSwitch supports upto 1016 ports, and BTW they can support 1016 VLANS if needed, but an ESX server doesn’t support that many VM’s. :)  


17. What is Promiscuous Mode on vSwitch ? What happens if it sets to Accept?
     If the promiscuous mode set to Accept, all the communication is visible to all the virtual machines, in other words all the packets are sent to all the ports on vSwitch
     If the promiscuous mode set to Reject, the packets are sent to inteded port, so that the intended virtual machine was able to see the communication.

18. What is MAC address Changes ? What happens if it is set to Accept ?
When we create a virtual machine the configuration wizard generates a MAC address for that machine, you can see it in the .vmx (VM Config) file. If it doesn't matches with the MAC address in the OS this setting does not allow incoming traffic to the VM. So by setting Reject Option both MAC addresses will be remains same, and the incoming traffic will be allowed to the VM.


19. What is Forged Transmits ? What happens if it is set to Accept ?
When we create a virtual machine the configuration wizard generates a MAC address for that machine, you can see it in the .vmx (VM Config) file. If it doesn't matches with the MAC address in the OS this setting does not allow outgoing traffic from the VM. So by setting Reject Option both MAC addresses will be remains same, and the outgoing traffic will be allowed from the VM.

NOTE: Configuring VMware vSwitch security settings: Don’t trust defaults


20. What are the core services of VC ?
VM provisioning , Task Scheduling and Event Logging


21. Can we do vMotion between two datacenters ? If possible how it will be?
Yes we can do vMotion between two datacenters, but the mandatory requirement is the VM should be powered off.


22. What is VC agent? and what service it is corresponded to? What are the minimum req's for VC agent installation ?
VC agent is an agent installed on ESX server which enables communication between VC and ESX server.
The daemon  associated with it is called vmware-hostd , and the service which corresponds to it is called as mgmt-vmware, in the event of VC agent failure just restart the service by typing the following command at the service console       

     " service mgmt-vmware restart " 
VC agent installed on the ESX server when we add it to the VC, so at the time of installtion if you are getting an error like " VC Agent service failed to install ", check the /Opt size whether it is sufficient or not.


23. How can you edit VI Client Settings and VC Server Settings ?
Click Edit Menu on VC and Select Client Settings to change VI settings
Click Administration Menu on VC and Select VC Management Server Configuration to Change VC Settings

24. What are the files that make a Virtual Machine  ?
     .vmx - Virtual Machine Configuration File
     .nvram - Virtual Machine BIOS
     .vmdk - Virtual Machine Disk file
     .vswp - Virtual Machine Swap File
     .vmsd - Virtual MAchine Snapshot Database
     .vmsn - Virtual Machine Snapshot file
     .vmss - Virtual Machine Suspended State file
     .vmware.log - Current Log File
     .vmware-#.log - Old Log file


25. What are the devices that can be added while the virtual Machine running
In VI 3.5 we can add Hard Disk and NIC's while the machine running.

In vSphere 4.0 we can add Memory and Processor along with HDD and NIC's while the machine running 


26. How to set the time delay for BIOS screen for a Virtual Machine?
Right Click on VM, select edit settings, choose options tab and select boot option, set the delay how much you want.


27. What is a template ?
We can convert a VM into Template, and it cannot be powered on once its changed to template. This is used to quick provisioning of VM's.


23. What to do to customize the windows virtual machine clone,?
copy the sysprep files to Virtual center directory on the server, so that the wizard will take the advantage of it.


24. What to do to customize the linux/unix virtual machine clone,?
VC itself includes the customization tools, as these operating systems are available as open source.


25. Does cloning from template happens between two datacenters ?
Yes.. it can, if the template in one datacenter, we can deploy the vm from that template in another datacenter without any problem.

26. What are the common issues with snapshots? What stops from taking a snapshot and how to fix it ?
If you configure the VM with Mapped LUN's, then the snapshot failed. If it is mapped as virtual then we can take a snapshot of it.
If you configure the VM with Mapped LUN's as physical, you need to remove it to take a snapshot.


27. What are the settings that are taken into to consideration when we initiate a snapshot ?
Virtual Machine Configuration (What hardware is attached to it)
State of the Virtual Machine Hard Disk file ( To revert back if needed)
State of the Virtual Machine Memory (if it is powered on)


28. What are the requirements for Converting a Physical machine to VM ?
An agent needs to be installed on the Physical machine
VI client needs to be installed with Converter Plug-in
A server to import/export virtual machines


29. What is VMWare consolidated backup ?
It is a backup framework, that supports 3rd party utilities to take backups of ESX servers and Virtual Machines. Its not a backup service.


30. To open the guided consolidation tool, what are the user requirements ?
The user must be member of administrator, The user should have "Logon as service" privileges - To give a user these privileges,open local sec policy, select Logon as service policy and add the user the user should have read access to AD to send queries
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VMware 4.1 Questions
1. What is HA?
VMware HA delivers the availability needed by many applications running in virtual machines, independent of the operating system and application running in it. VMware HA provides uniform, cost-effective failover protection against hardware and operating system failures within your virtualized IT environment. 
• Monitors virtual machines to detect operating system and hardware failures. 
• Restarts virtual machines on other physical servers in the resource pool without manual intervention when server failure is detected.
• Protects applications from operating system failures by automatically restarting virtual machines when an operating system failure is detected.

2. How HA works?
VMware HA continuously monitors all servers in a resource pool and detects server failures. An agent placed on each server maintains a “heartbeat” with the other servers in the resource pool and a loss of “heartbeat” initiates the restart process of all affected virtual machines on other servers. VMware HA ensures that sufficient resources are available in the resource pool at all times to be able to restart virtual machines on different physical servers in the event of server failure. Restart of virtual machines is made possible by the Virtual Machine File System (VMFS) clustered file system which gives multiple ESX Server instances read-write access to the same virtual machine files, concurrently. VMware HA is easily configured for a resource pool through VirtualCenter.
Key Features of VMware HA

• Automatic detection of server failures. Automate the monitoring of physical server availability. HA detects server failures and initiates the virtual machine restart without any human intervention.

• Resource checks. Ensure that capacity is always available in order to restart all virtual machines affected by server failure. HA continuously monitors capacity utilization and “reserves” spare
capacity to be able to restart virtual machines.

• Automatic restart of virtual machines. Protect any application with automatic restart in a different physical server in the resource pool.

• Intelligent choice of servers (when used with VMware Distributed Resource Scheduler (DRS)). Automate the optimal placement of virtual machines restarted after server failure.

The VMware HA Solution
With VMware HA, a set of ESX Server hosts is combined into a cluster with a shared pool of resources. VMware HA monitors all hosts in the cluster. If one of the hosts fails, VMware HA immediately responds by restarting each affected virtual machine on a different host.

Using VMware HA has a number of advantages:
• Minimal setup and startup. The New Cluster wizard is used for initial setup. Hosts and new virtual machines can be added using the Virtual Infrastructure Client.
• Reduced hardware cost and setup. In a traditional clustering solution, duplicate hardware and software must be available, and the components must be connected and configured properly. When using VMware HA clusters, you must have sufficient resources to accommodate the number of hosts for which you want to guarantee failover. However, the VirtualCenter Server takes care of all other aspects of the resource management.
• VMware HA "democratizes" high availability by making it available and cost-justifiable for any application, regardless of hardware and operating system platform. VMware HA is focused on hardware failure, not on operating system or software failure. If you need greater levels and guarantees of availability to handle those situations, you can consider using both VMware HA and traditional high availability approaches together.

VMware HA Features
Using a cluster enabled for VMware HA provides the following features:
• Automatic failover is provided on ESX Server host hardware failure for all running virtual machines within the bounds of failover capacity.
VMware HA provides automatic detection of server failures and initiates the virtual machine restart without any human intervention.
• VMware HA can take advantage of DRS to provide for dynamic and intelligent resource allocation and optimization of virtual machines after failover. After a host has failed and virtual machines have been restarted on other hosts, DRS can provide further migration recommendations or migrate virtual machines for more optimum host placement andbalanced resource allocation.
• VMware HA supports easy-to-use configuration and monitoring using VirtualCenter. HA ensures that capacity is always available (within the limits of specified failover capacity) in order to restart all virtual machines affected by server failure (based on resource reservations configured for the virtual machines.)
• HA continuously monitors capacity utilization and "reserves" spare capacity to be able to restart virtual machines. Virtual Machines can fully utilize spare failover capacity when there hasn't been a failure.

3. What is DRS?

Align Resources to Meet Business Needs
VMware DRS continuously monitors utilization across resource pools and intelligently aligns resources with business needs, enabling us to:
• Dynamically allocate IT resources to the highest priority applications. Create rules and policies to prioritize how resources are allocated to virtual machines. 
• Give IT autonomy to business organizations. Provide dedicated IT infrastructure to business units while still achieving higher hardware utilization through resource pooling.
• Empower business units to build and manage virtual machines within their resource pool while giving central IT control over hardware resources.

Balance Your Computing Capacity
VMware DRS continuously balances computing capacity in resource pools to deliver the performance, scalability and availability not possible with physical infrastructure. VMware DRS allows us to:
• Improve service levels for all applications. VMware DRS continuously balance capacity will ensure that each virtual machine has access to appropriate resources at any point in time.
• Easily deploy new capacity. VMware DRS will seamlessly take advantage of the additional capacity of new servers added to a resource pool by redistributing virtual machines without system disruption.
• Automate planned server maintenance. VMware DRS can automatically migrate all virtual machines off physical servers to enable scheduled server maintenance with zero downtime.
• Dramatically increase system administrator productivity. Enable system administrators to monitor and effectively manage more IT infrastructure.

Reduce Energy Consumption in the Datacenter
VMware Distributed Power Management (DPM) continuously optimizes power consumption in the datacenter. When virtual machines in a DRS cluster need fewer resources, such as during nights and weekends, DPM consolidates workloads onto fewer servers and powers off the rest to reduce power consumption. When virtual machine resource requirements increase (such as when users log into applications in the morning), DPM brings powered-down hosts back online to ensure service levels are met.
VMware Distributed Power Management allows IT organizations to:
• Cut ongoing power and cooling costs by up to 20% in the datacenter during low utilization time periods. 
• Automate management of energy efficiency in the datacenter
VMware DRS (with DPM) is included in the VMware vSphere Enterprise and Enterprise Plus edition. DRS and DPM leverage VMware vMotion (live migration) to balance load and optimize power consumption with no downtime. 
Features
The following is a list of the key features of VMware DRS.
• Aggregation of physical server resources. Manage CPU and memory across a group of physical servers as a uniform shared pool of resources.
• Flexible hierarchical organization. Organize resource pools hierarchically to match available IT resources to the business organization. VMware DRS ensures that resource utilization is maximized while business units retain control and autonomy of their infrastructure. Resource pools can be flexibly added, removed, or reorganized as business needs or organization change. 
• Priority Settings. Assign priorities in the form of shares or reservations to virtual machines within resource pools and to sub resource pools to reflect business priorities. For example, the production sub resource pool can have higher shares of the total resources in a cluster and business critical applications within the production resource pool can have fixed guarantees(reservations) of CPU bandwidth and memory,
• Management of sets of virtual machines running a distributed application. Optimize the service level of distributed applications by controlling the aggregate allocation of resources for the entire set of virtual machines running the distributed application.
• Affinity Rules. Create rules that govern placement of virtual machines on physical servers. For example, a group of virtual machines can be set to always run on the same server for performance reasons. Alternatively, certain virtual machines can be set to always run on different servers to increase availability. New in vSphere 4.1 is the ability to restrict placement of virtual machines to a group of physical servers in a cluster. This is useful for controlling the mobility of virtual machines that run software licensed for a specific group of physical servers. In addition, this feature can be used to keep sets of virtual machines on different racks or blade systems for availability reasons. 
• Power Management. Reduce energy consumption in the datacenter by using the Distributed Power Management (DPM) feature of DRS to consolidate workloads and power off servers when they are not needed by the virtual machines in the cluster. When resource requirements of virtual machines increase, DPM brings hosts back online so service levels can be met.
• Manual and Automatic Mode. VMware DRS collects resource usage information from servers and virtual machines, and then generates recommendations to optimize virtual machine allocation. These recommendations can be executed automatically or manually. 
o Initial placement. When a virtual machine is first powered on, VMware DRS either automatically places the virtual machine on the most appropriate physical server or makes a recommendation. 
o Continuous optimization. VMware DRS continuously optimizes resource allocations based on defined resource allocation rules and resource utilization. The resource allocation changes can be automatically executed by performing live migration of virtual machines through vMotion. Alternatively, in manual mode, VMware DRS provides execution recommendations for system administrators.
• Maintenance mode for servers. Perform maintenance on physical servers without disruption to virtual machines and end users. When a physical server is placed in maintenance mode, VMware DRS identifies alternative servers where the virtual machines can run. Based on automation mode settings, the virtual machines are either automatically moved to use the alternative servers, or the system administrator performs the move manually using the VMware DRS recommendations as a guideline.
• Large-scale management. Manage CPU and memory across up to 32 servers and 1280 virtual machines per DRS cluster.

4. What is vMotion?

Experience Game-changing Virtual Machine Mobility
VMware vMotion technology, leverages the complete virtualization of servers, storage and networking to move an entire running virtual machine instantaneously from one server to another. VMware vMotion uses VMware’s cluster file system to control access to a virtual machine’s storage. During a vMotion, the active memory and precise execution state of a virtual machine is rapidly transmitted over a high speed network from one physical server to another and access to the virtual machines disk storage is instantly switched to the new physical host. Since the network is also virtualized by the VMware host, the virtual machine retains its network identity and connections, ensuring a seamless migration process.

VMware vMotion allows you to:
• Perform live migrations with zero downtime, undetectable to the user.
• Continuously and automatically optimize virtual machines within resource pools.
• Perform hardware maintenance without scheduling downtime and disrupting business operations.
• Proactively move virtual machines away from failing or underperforming servers.



Reliably Manage Live Migrations with Ease
Benefit from the reliability and manageability derived from a production-proven product used by thousands of customers for years. Live migration of virtual machines across your infrastructure is surprisingly simple with functionality that lets you:
• Perform multiple concurrent migrations to continuously optimize a virtual IT environment.
• Identify the optimal placement for a virtual machine in seconds with a migration wizard providing real-time availability information.
• Migrate any virtual machine running any operating system across any type of hardware and storage supported by vSphere, including Fibre Channel SAN, NAS and iSCSI SAN.
• Prioritize live migrations to ensure that mission-critical virtual machines maintain access to the resources they need.
• Schedule migrations to happen at pre-defined times, and without an administrator’s presence.
• Maintain an audit trail with a detailed record of migrations.

How Does VMware VMotion Work?

Live migration of a virtual machine from one physical server to another with VMware VMotion is enabled by three
underlying technologies.

First, the entire state of a virtual machine is encapsulated by a set of files stored on shared storage such as Fibre Channel or iSCSI Storage Area Network (SAN) or Network Attached Storage (NAS). VMware vStorage VMFS allows multiple installations of VMware ESX® to access the same virtual machine files concurrently.

Second, the active memory and precise execution state of the virtual machine is rapidly transferred over a high speed network, allowing the virtual machine to instantaneously switch from running on the source ESX host to the destination ESX host. VMotion keeps the transfer period imperceptible to users by keeping track of on-going memory transactions in a bitmap.
Once the entire memory and system state has been copied over to the target ESX host, VMotion suspends the source virtual machine, copies the bitmap to the target ESX host, and resumes the virtual machine on the target ESX host. This entire process takes less than two seconds on a Gigabit Ethernet network.

Third, the networks being used by the virtual machine are also virtualized by the underlying ESX host, ensuring that even after the migration, the virtual machine network identity and network connections are preserved. VMotion manages the virtual MAC address as part of the process. Once the destination machine is activated, VMotion pings the network router to ensure that it is aware of the new physical location of the virtual MAC address.
Since the migration of a virtual machine with VMotion preserves the precise execution state, the network identity, and the active network connections, the result is zero downtime and no disruption to users.

Key Features of vMotion.

Reliability.
Proven by thousands of customers in production environments since 2004, VMotion continues to set the standard for the most dependable live migration capabilities.

Performance.
Perform live migrations with downtime unnoticeable to the end users. Optimal use of CPU and network resources ensures that the live migrations occur quickly and efficiently.

Interoperability.
Migrate virtual machines running any operating system across any type of hardware and storage supported by VMware ESX.
• Support for Fibre Channel SAN.
Implement live migration of virtual machines utilizing a wide range of up to 4GB Fibre Channel SAN storage systems.
• NAS and iSCSI SAN support. Implement live migration of virtual machines with lower-cost,
more easily managed shared storage.
• Customizable CPU compatibility settings. Ensure that virtual machines can be migrated across different
versions of hardware. Enable virtual machines to benefit from the latest CPU innovations.
• New - Enhanced VMotion Compatibility. Live migrate virtual machines across different generations of
hardware. Migrate virtual machines from older servers to new ones without disruption or downtime.

Manageability
• Migration wizard.
Quickly identify the best destination for a virtual machine using real-time information provided by migration wizard.
• Multiple concurrent migrations.
Perform multiple concurrent migrations to continuously optimize virtual machine placement across the entire
IT environment.
• Priority levels.
Assign a priority to each live migration operation to ensure that the most important virtual machines always have access to the resources they need.
• Scheduled migration tasks.
Automate migrations to happen at pre-defined times, and without an administrator’s presence.
• Migration audit trail.
Maintain a detailed record of migration operations, including date/time and the administrators responsible for initiating them.

5. What is VMware Storage VMotion?

VMware Storage VMotion is a component of VMware vSphere™ that provides an intuitive interface for live migration of virtual machine disk files within and across storage arrays with no downtime or disruption in service. Storage VMotion relocates virtual machine disk files from one shared storage location to another shared storage location with zero downtime, continuous service availability and complete transaction integrity. Storage VMotion enables organizations to perform proactive storage migrations, simplify array migrations, improve virtual machine
storage performance and free up valuable storage capacity. Storage VMotion is fully integrated with VMware vCenter Server to provide easy migration and monitoring.

How is VMware Storage VMotion Used in the Enterprise?

Customers use VMware Storage VMotion to:

• Simplify array migrations and storage upgrades.
The traditional process of moving data to new storage is cumbersome, time-consuming and disruptive. With Storage VMotion, IT organizations can accelerate migrations while minimizing or eliminating associated service disruptions, making it easier, faster and more cost-effective to embrace new storage platforms and file formats, take advantage of flexible leasing models, retire older, hard-to-manage storage arrays and to conduct storage upgrades and migrations based on usage and priority policies. Storage VMotion works with any operating system and storage hardware platform supported by VMware ESX™, enabling customers to use a heterogeneous mix
of datastores and file formats.

• Dynamically optimize storage I/O performance.
Optimizing storage I/O performance often requires reconfiguration and reallocation of storage, which can be a
highly disruptive process for both administrators and users and often requires scheduling downtime. With Storage
VMotion, IT administrators can move virtual machine disk files to alternative LUNs that are properly configured to
deliver optimal performance without the need for scheduled downtime, eliminating the time and cost associated with traditional methods.

• Efficiently manage storage capacity.
Increasing or decreasing storage allocation requires multiple manual steps, including coordination between groups, scheduling downtime and adding additional storage. This is then followed by a lengthy migration of virtual machine disk files to the new datastore, resulting in significant service downtime. Storage VMotion improves this process by enabling administrators to take advantage of newly allocated storage in a non-disruptive manner. Storage VMotion can also be used as a storage tiering tool by moving data to different types of storage platforms based the data value, performance requirements and storage costs.

How Does VMware Storage VMotion Work?

VMware Storage VMotion allows virtual machine storage disks to be relocated to different datastore locations with no downtime, while being completely transparent to the virtual machine or the end user.

Before moving a virtual machines disk file, Storage VMotion moves the “home directory” of the virtual machine to the new location. The home directory contains meta data about the virtual machine (configuration, swap and log files). After relocating the home directory, Storage VMotion copies the contents of the entire virtual machine storage disk file to the destination storage host, leveraging “changed block tracking” to maintain data integrity during the migration process. Next, the software queries the changed block tracking module to determine what regions of the disk were written to during the first iteration, and then performs a second iteration of copy, where those regions that were changed during the first iteration copy (there can be several more iterations). 

Once the process is complete, the virtual machine is quickly suspended and resumed so that it can begin using the virtual machine home directory and disk file on the destination datastore location. Before VMware ESX allows the virtual machine to start running again, the final changed regions of the source disk are copied over to the destination and the source home and disks are removed. 

This approach guarantees complete transactional integrity and is fast enough to be unnoticeable to the end user.

Key Features of VMware Storage VMotion

Complete transaction integrity.
No interruption or downtime for users and applications during virtual machine storage disk migrations.

Interoperability.
Storage VMotion can migrate storage disk files for virtual machines running any operating system across any type of hardware and storage supported by VMware ESX.









1) How we manage the licenses, i.e. timely updating licenses, briefly explain?


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2) If we found HA issue, what are steps we should follow to resolve the issues?

To troubleshoot HA errors:

Note: Most of these troubleshooting steps are done on the ESX console. 
1.Run this command to verify that host name is in lowercase and is fully qualified:

hostname


2.Run this command to verify that hostname is shortname only and is in lowercase:

hostname –s


3.Run this command to verify that the correct service console IP is displayed:

hostname –i


4.Verify that the host name in /etc/hosts is lowercase and both FQDN and shortname are present. 
5.Verify that the search domain is present in the /etc/resolv.conf file and is in lowercase. 
6.Verify that the host name in /etc/sysconfig/network is FQDN and is in lowercase. 
7.Verify that the host name in the /etc/vmware/esx.conf file is FQDN and is in lowercase. 
8.Verify that the system name returned by the uname -a command is in lowercase. 
9.Verify that the host name is in your DNS server and is in lowercase. To do this, run these commands: 
a.nslookup 

Where is the name of the host.

This command should return the service console IP.


b.nslookup 

Where is the FQDN name of the host.

This command should return the service console IP.


c.nslookup 

Where is the IP address of the host.

This command should return the FQDN of the host


10.Make sure the route for the service console is correct. To do this, from each host, ping the other hosts in the environment.
11.Verify that all primary service consoles have the same name.
12.Verify that all primary service consoles are in the same IP subnet.
13.If the vmkernel port group of vMotion is on same vSwitch as primary Service Console port group, add das.allowVmotionNetworks=1 to the advanced settings of
HA.
14.If the host has multiple service consoles, add das.allowNetwork0 to the Advanced HA Settings of the cluster to ensure that only the primary service
console is allowed. For more information, see Incompatible HA Networks appearing when attempting to configure HA (High Availability) (1006541).
15.Verify that you have the appropriate licenses available for HA. To do this, in LM Tools, perform a status enquiry and verify that you have VC_DAS licenses
available.
If you are unable to configure HA after verifying these troubleshooting steps:
1.Run this command on the ESX host to stop vpxa:

service vmware-vpxa stop

The host appears as not responding in the vCenter Server after a while.


2.Run these commands to uninstall aam:
1.rpm -qa | grep aam
2.rpm -e (package names output from command above)
3.rpm -e (other package names output from command above)
4.find / -name aam

Note: Ensure to delete the directories listed by this command.


3.Disconnect the ESX host from the vCenter Server.
4.Re-connect the host to the vCenter Server. This forces the VPXA package and the the HA packages to re-deploy.
5.Re-configure all the hosts for HA.
6.Upgrade to ESX 3.5 U4 or later and vCenter Server 2.5U4 or later.
7.After upgrading, add das.bypassNetCompatCheck=true to the Advanced HA Settings of the cluster, if it continues to have issues.
If your issue continues to exist after performing these steps, contact your network or storage administrator.

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3) Redundancy between NICs in an ESX server & how many minimum NICs required for esx


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4) Minimum requirements for VMotion configure?


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5) How licenses calculated/purchased for VMware environment?


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6) What are the partitions of an ESX server?

Service Console Partitions and Sizes for Each ESX Server Host

Mount Point Partition Size Description

/dev/sda (Primary)

/boot ext3 250 MB Change for additional space for upgrades

N/A swap 1600 MB Change for maximum service console swap size

/ ext3 5120 MB Change for additional space in root

/dev/sda (Extended)

/var ext3 4096 MB Create partition to avoid overfilling root with log files

/tmp ext3 1024 MB Create partition to avoid overfilling root with temporary files

/opt ext3 2048 MB Create partition to avoid overfilling root with VMware HA log files

/home ext3 1024 MB Create partition to avoid overfilling root with agent / user files

vmkcore 100 MB Pre-configured

Free Space (Optional) Auto-configured and used for local VMFS-3 volume (needed for virtual machines running Microsoft’s Clustering Software.


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7) Whether we need licenses for HA, DRS feature?
Yes,

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8) What should be the main reason for purple screen errors?

Purple Screen of Death

A Purple Screen of Death as seen in VMware ESX Server 3.0 In the event of a hardware error, the vmkernel can 'catch' a Machine Check Exception.This results
in an error message displayed on a purple console screen. This is colloquially known as a PSOD, or Purple Screen of Death.

Upon displaying a PSOD, the vmkernel writes debug information to the core dump partition. This information, together with the error codes displayed on the
PSOD can be used by VMware support to determine the cause of the problem.



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9) How to configure virtual switches & what is port-group & what is VLAN?


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10) Whether HA use VMotion or not?

No, it requires DRS.

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11) Whether DRS use VMotion or not?

yes

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12) What are processes & port numbers for virtual center, HA running in ESX?

Ports and descriptions:

80 – Required for direct HTTP connections. Port 80 redirects requests to HTTPS port 443.

443 - Listens for connections from the vSphere Client, vSphere Web Access Client, and other SDK clients. Open port 443 in the firewall to enable the vCenter
Server system to receive data from the vSphere Client.

389 - This port is used for Lightweight Directory Access Protocol (LDAP) services. Who says LDAP, says Active Directory Services for the vCenter Server
group.

636 – SSL port of the local instance for vCenter Linked Mode. It’s the port of the local vCenter Server ADAM Instance.

902 - Used to send data to managed hosts. To send data to your ESX or ESXi hosts. Also this port is used for remote console access to virtual machines from
vSphere Client. This port must not be blocked by firewalls between the server and the hosts or between hosts.

902/903 - Used by the vSphere Client to display virtual machine consoles.

8080 – vCenter Management Webservices HTTP.

8443 - Secure connections for vCenter Management Webservices HTTPS.

60099 - Used to stream inventory object changes to SDK clients. Firewall rules for this port on the vCenter Server can be set to block all, except from and
to localhosts if the clients are installed on the same host as the vCenter Server service.

--------Various services are installed when you deploy vCenter, in total 5 services are installed----------

1.VMware VirtualCenter Server: Heart of vCenter
2.VMware mount service for VirtualCenter: used during cloning operation or while deploying from template
3.VMware VirtualCenter management webservices: Web management services run on it.
4.VMwareVCMSDS:ADAM services for linked mode
5.VMware vCenter orchestrator configuration: use for vCenter orchestrator

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13) In ESX2.5.2 how we take backups of vm files?


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14) Explain the purpose of Redo log files?


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15) VM is not able to power off, how to trouble shoot d issues?

Powering off the virtual machine

To determine if you must use the command line, attempt to power off the virtual machine:
1.Connect VMware Infrastructure (VI) Client to the Virtual Center Server. Right-click on the virtual machine and click Power off.
2.Connect VI Client directly to the ESX host. Right-click on the virtual machine and click Power off.

If this does not work, you must use the command line method.
Determining the virtual machine's state
1.Determine the host on which the virtual machine is running. This information is available in the virtual machine's Summary tab when viewed in the VI Client
page.
2.Log in as root to the ESX host using an SSH client.
3.Run the following command to verify that the virtual machine is running on this host:

# vmware-cmd -l

The output of this command returns the full path to each virtual machine running on the ESX host. Verify that the virtual machine is listed, and record the
full path for use in this process. For example:

# /vmfs/volumes///.vmx


4.Run the following command to determine the state in which the ESX host believes the virtual machine to be operating:

# vmware-cmd getstate

If the output from this command is getstate() = on, the VirtualCenter Server may not be communicating with the host properly. This issue must be addressed in
order to complete the shutdown process.

If the output from this command is getstate() = off, the ESX host may be unaware it is still running the virtual machine. This article provides additional
assistance in addressing this issue.
Powering off the virtual machine while collecting diagnostic information using the vm-support script

Use the following procedure when you want to investigate the cause of the issue. This command attempts to power off the virtual machine while collecting
diagnostic information. Perform these steps in order, as they are listed in order of potential impact to the system if performed incorrectly.

Perform these steps first:
1.Determine the WorldID with the command:

# vm-support -x


2.Kill the virtual machine by using the following command in the home directory of the virtual machine:

# vm-support -X 

This can take upwards of 30 minutes to terminate the virtual machine.

Note: This command uses several different methods to stop the virtual machine. When attempting each method, the command waits for a pre-determined amount of
time. The timeout value can be configured to be 0 by adding -d0 to switch to the vm-support command.
If the preceding steps fail, perform the following steps for an ESX 3.x host:
1.List all running virtual machines to find the VMID of the affected virtual machine with the command:

# cat /proc/vmware/vm/*/names


2.Determine the master world ID with the command:

# less -S /proc/vmware/vm/####/cpu/status


3.Scroll to the right with the arrow keys until you see the group field. It appears similar to:

Group
vm.####


4.Run the following command to shut the virtual machine down with the group ID:

# /usr/lib/vmware/bin/vmkload_app -k 9 ####
If the preceding steps fail, perform the following steps for an ESX 4.x host:
1.List all running virtual machines to find the vmxCartelID of the affected virtual machine with the command:

# /usr/lib/vmware/bin/vmdumper -l


2.Scroll through the list until you see your virtual machine's name. The output appears similar to:

vmid=5151 pid=-1 cfgFile="/vmfs/volumes/4a16a48a-d807aa7e-e674-001e4ffc52e9/mdineeen_test/vm_test.vmx" uuid="56 4d a6 db 0a e2 e5 3e-a9 2b 31 4b 69
29 15 19" displayName="vm_test" vmxCartelID=####


3.Run the following command to shut the virtual machine down with the vmxCartelID:

# /usr/lib/vmware/bin/vmkload_app -k 9 ####
Powering off the virtual machine using the vmware-cmd command

This procedure uses the ESX command line tool, and attempts to gracefully power off the virtual machine. It works if the virtual machine's process is running
properly and is accessible. If unsuccessful, the virtual machine's process may not be running properly and may require further troubleshooting.
1.From the Service Console of the ESX host, run the following command:

vmware-cmd stop

Note: is the complete path to the configuration file, as determined in the previous section. To verify that it is stopped, run the command:

# vmware-cmd getstate


2.From the Service Console of the ESX host, run the command:

# vmware-cmd stop hard

Note: is the complete path to the configuration file, as determined in the previous section. To verify that it is stopped, run the command:

# vmware-cmd getstate


3.If the virtual machine is still inaccessible, proceed to the next section.
Using the ESX command line to kill the virtual machine

If the virtual machine does not power off using the steps in this article, it has likely lost control of its process. You need to manually kill the process
at the command line.

Caution: This procedure is potentially hazardous to the ESX host. If you do not identify the appropriate process id (PID), and kill the wrong process, it may
have unanticipated results. If you are not comfortable with the following procedure, contact VMware Technical Support and open a Service Request. Please
refer to this article when you create the SR.
1.To determine if the virtual machine process is running on the ESX host, run the command:

# ps auxwww |grep -i .vmx

The output of this command appears similar to the following if the .vmx process is running:

root 3093 0.0 0.3 2016 860 ? S< Jul30 0:17 /usr/lib/vmware/bin/vmkload_app /usr/lib/vmware/bin/vmware-vmx -ssched.group=host/user -# name=VMware ESX Server;version=3.5.0;licensename=VMware ESX Server;licenseversion=2.0 build-158874; -@ pipe=/tmp/vmhsdaemon-0/vmx569228e44baf49d1; /vmfs/volumes/49392e30- 162037d0-17c6-001f29e9abec//.vmx

The process ID (PID) for this process is in bold. In this example, the PID is 3093. Take note of this number for use in the following steps.

Caution: Ensure that you identify the line specific only to the virtual machine you are attempting to repair. If you continue this process for another
virtual machine the one in question, you can cause downtime for the other virtual machine.

If the .vmx process is listed, it is possible that the virtual machine has lost control of the process and that it must be stopped manually.


2.To kill the process, run the command:

# kill 


3.Wait 30 seconds and check for the process again.
4.If it is not terminated, run the command:

# kill -9 


5.Wait 30 seconds and check for the process again.
6.If it is not terminated, the ESX host may need to be rebooted to clear the process. This is a last resort option, and should only be attempted if the
preceding steps in this article are unsuccessful.


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16) Why we use two different ports for licenses, and what r those port No.?

27000 --- License transactions from ESX Server 3i to the license server (lmgrd.exe).|Outgoing TCP|

27010 --- License transactions from ESX Server 3i to the license server (vmwarelm.exe).|Outgoing TCP|

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17) VC server is not coming up, how to troubleshoot?


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18) Difference between ESX3.5 & 4.0?


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19) Briefly describe about update Manager, is it possible to update the powered off vms by update manager?


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20) Explain VMware Snapshot & what is d command to take a snapshot?


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21) Suppose we have 3 port groups configured in a single Vswitch (connected to single physical NIC of the esx host) with 3 different VLANs so how d VMs from
one VLAN will communicate to another VM of different VLAN?

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22) What is d command to list all the running VMs & registered VMs?

Run the vm-support -x command to show which virtual machines are currently running on the ESX host.

Run the vmware-cmd -l command to display the names of the virtual machines registered on this host.


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23) What is d command to list d HBAs?

esxcfg-scsidevs -a (-a|--hbas Print HBA devices with identifying information)

esxcfg-scsidevs -A (-A|--hba-device-list Print a mapping between HBAs and the devices it provides paths to.)

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24) What r d P2V conversion processes/tools available, how we can perform d P2V of a Linux server with d help of CLI commands (in case no specific tools
available)?

Converting a powered on Windows operating system (P2V)
Source Destination TCP Ports UDP Ports Notes

Converter server to Source computer 445, 139, 9089, 9090 137, 138 If the source computer uses NetBIOS, port 445 is not required. If NetBIOS is not being
used, ports 137, 138, and 139 are not required. If in doubt, make sure that none of the ports are blocked.
Note: Unless you have installed Converter server to the source computer, the account used for authentication to the source computer must have a password, the
source computer must have network file sharing enabled, and it cannot be using Simple File Sharing.
Converter server to VirtualCenter 443 Only required if the conversion target is VirtualCenter.
Converter client to Converter server 443 Only required if a custom installation was performed and the Converter server and client portions are on different
computers.
Source computer to ESX 443, 902 If the conversion target is VirtualCenter then only port 902 is required.

Converting a powered on Linux operating system (P2V)
Source Destination TCP Ports Notes
Converter server to Source computer 22 The Converter server must be able to establish an SSH connection with the source computer.
Converter client to Converter server 443 Only required if a custom installation was performed and the Converter server and client portions are on different
computers.
Converter server to VirtualCenter 443 Only required if the conversion target is VirtualCenter.
Converter server to ESX 443, 902, 903 If the conversion target is VirtualCenter, only ports 902 and 903 are required.
Converter server to Helper virtual machine 443
Helper virtual machine Source computer 22 The helper virtual machine must be able to establish an SSH connection with the source computer. By default the
helper virtual machine gets its IP address assigned by DHCP. If there is no DHCP server available on the network chosen for the target virtual machine you
must manually assign it an IP address.

Converting an existing virtual machine (V2V)
Source Destination TCP Ports UDP Ports Notes

Converter server to Fileshare path 445, 139 137, 138 This is only required for standalone virtual machine sources or destinations.

If the computer hosting the source or destination path uses NetBIOS, port 445 is not required. If NetBIOS is not being used, ports 137, 138, and 139 are not
required. If in doubt, make sure that none of the ports are blocked.
Converter client to Converter server 443 Only required if a custom installation was performed and the Converter server and client portions are on different
computers.
Converter server to VirtualCenter 443 Only required if the target is VirtualCenter.
Converter server to ESX 443, 902 If the conversion target is VirtualCenter, only port 902 is required.


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25) What is d command to check d status of a VM?

vmware-cmd getstate

Retrieve the list of VMs in inventory with the following command:
vmware-vim-cmd vmsvc/getallvms

[root@ESX-SRV-94 /]# vmware-vim-cmd vmsvc/getallvms
Vmid Name File Guest OS Version Annotation
160 VMVXP-1 [SAN-STORE-2] VMVXP-1/VMVXP-1.vmx winXPProGuest vmx-07
240 Ubuntu [ESX-Storage-94-2] Ubuntu/Ubuntu.vmx ubuntuGuest vmx-07


Then query each VM with their VMID:
vmware-vim-cmd vmsvc/power.getstate 

For example:
vmware-vim-cmd vmsvc/power.getstate 160

[root@ESX-SRV-94 /]# vmware-vim-cmd vmsvc/power.getstate 160
Retrieved runtime info
Powered on


------------------------------------------------------------------------------------------------------------------------------
26) What is d command to rescan the HBAs?

esxcfg-rescan

------------------------------------------------------------------------------------------------------------------------------
27) How to find the world ID of a particular VM and what is d VMware proprietary command to kill the same?

vm-support -x
esxcli vms vm list

List all running virtual machines on the system to see the World ID of the virtual machine you want to
stop.
esxcli vms vm list

2 Stop the virtual machine by running the following command.

esxcli vms vm kill --type --world-id 

The command supports three --type options. Try the types sequentially (soft before hard, hard before
force). The following types are supported through the --type option:
. soft – Gives the VMX process a chance to shut down cleanly (like kill or kill -SIGTERM)
. hard – Stops the VMX process immediately (like kill -9 or kill -SIGKILL)
. force – Stops the VMX process when other options do not work.
If all three options do not work, reboot your ESX/ESXi host to resolve the issue.

------------------------------------------------------------------------------------------------------------------------------
28) what is d command to add a route in esx to communicate to different network segment?

Configure the route using the command:

#route add -net 142.121.56.0 netmask 255.255.254.0 gw 224.58.175.1 Add the following line to /etc/rc.local so that route is set on boot:


#/sbin/route add -net 142.121.56.0 netmask 255.255.254.0 gw 224.58.175.1 To ensure the route holds on reboot, create an executable file.

To create an executable file:
1.Login to the ESX host using a SSH client.
2.Change the directory to /etc/init.d .
3.Run this command to create a file called routes:

#vi routes


4.Add this code to the file:

##! /bin/bash # case "$1" in 'start') echo "Adding additional routes... "

/sbin/route add -net 172.31.3.0 netmask 255.255.255.0 gw 172.31.8.1; echo ;; *) echo "Usage: $0 { start }" ;; esac


5.Save the file and exit the vi editor.


6.Run this command to make the file executable:

#chmod 777 routes


7.Change the directory to /etc/rc3.d.
8.Run this command to create a symbolic link to that file:

#ln /etc/init.d/routes

9.Reboot the ESX host for the changes to take effect.

------------------------------------------------------------------------------------------------------------------------------

29) What is d default size of the swap partition & SC MEMORY?

1600MB SWAP, 400 MB (MAX 800MB)

------------------------------------------------------------------------------------------------------------------------------

30) How to increase SC memory after the esx build?



•ESX Host – 8GB RAM -> Default allocated Service Console RAM = 300MB
•ESX Host – 16GB RAM -> Default allocated Service Console RAM = 400MB
•ESX Host – 32GB RAM -> Default allocated Service Console RAM = 500MB
•ESX Host – 64GB RAM -> Default allocated Service Console RAM = 602MB
•ESX Host – 96GB RAM -> Default allocated Service Console RAM = 661MB
•ESX Host – 128GB RAM -> Default allocated Service Console RAM = 703MB
•ESX Host – 256GB RAM -> Default allocated Service Console RAM = 800MB

cp /etc/vmware/esx.conf /etc/vmware/esx.conf.old
cp /boot/grub/grub.conf /boot/grub/grub.conf.old
/bin/sed -i -e ‘s/272/800/’ /etc/vmware/esx.conf
/bin/sed -i -e ‘s/512/800/’ /etc/vmware/esx.conf
/bin/sed -i -e ‘s/272M/800M/’ /boot/grub/grub.conf
/bin/sed -i -e ‘s/512M/800M/’ /boot/grub/grub.conf
/bin/sed -i -e ‘s/277504/818176/’ /boot/grub/grub.conf
/bin/sed -i -e ‘s/523264/818176/’ /boot/grub/grub.conf

-----------------------------------------------------------------------------------------


31) What r d port No. for Vmotion & VMware converter?

ESX 4.x 8000 TCP ESX/ESXi Host (VM Target) TO ESX/ESXi Host (VM Source) VMotion Communication on VMKernel Interface
ESX 4.x 8000 TCP ESX/ESXi Host (VM Source) TO ESX/ESXi Host (VM Target) VMotion Communication on VMKernel Interface

ESXi 4.x 8000 TCP ESX/ESXi Host (VM Target) TO ESX/ESXi Host (VM Source) VMotion Communication on VMkernel Interface
ESXi 4.x 8000 TCP ESX/ESXi Host (VM Source) TO ESX/ESXi Host (VM Target) VMotion Communication on VMkernel Interface

Converter 4.x 22 TCP Helper Virtual Machine Source Computer to be converted Required for conversion of Linux-based source computers (data flows from source
to VM)

Converter 4.x 22 TCP vCenter Converter Server Source Computer to be converted Required for conversion of Linux-based source computers

Converter 4.x 137 UDP vCenter Converter Server Source Computer to be converted For hot migration. Not required if the source computer does not use NetBIOS

Converter 4.x 138 UDP vCenter Converter Server Source Computer to be converted For hot migration. Not required if the source computer does not use NetBIOS

Converter 4.x 139 TCP vCenter Converter Server Source Computer to be converted For hot migration. Not required if the source computer does not use NetBIOS

Converter 4.x 443 TCP vCenter Converter Client vCenter Converter Server Only required if the Converter Client and Converter Server were installed on
different systems

Converter 4.x 443 TCP Source Computer to be converted ESX/ESXi Host Required for destination VM access when target is ESX/ESXi/vCenter

Converter 4.x 443 TCP Source Computer to be converted vCenter Server Required if vCenter Server is the conversion target

Converter 4.x 443 TCP vCenter Converter Server vCenter Server Required if vCenter Server is the conversion target

Converter 4.x 443 TCP vCenter Converter Server ESX/ESXi Host Required for system conversion

Converter 4.x 443 TCP vCenter Converter Server Helper Virtual Machine Required for conversion of Linux-based source computers

Converter 4.x 445 TCP vCenter Converter Server Source Computer to be converted Required for system conversion. Not required if the source computer uses
NetBIOS

Converter 4.x 902 TCP Source Computer to be converted ESX/ESXi Host Required for data transport during cloning of system to be converted to target ESX/ESXi
Host

Converter 4.x 9089, 9090 TCP vCenter Converter Server Source Computer to be converted Required for system conversion. Remote agent deployment

------------------------------------------------------------------------------------------------------------------------------
32) How to create Vmkcore partition after the esx build?

using parted we can create vmkcore partition if there is free space availabe else first free up about 100MB space on disk by resizing the root or any other
partion on the disk and then create new vmkcore partion with fc filesystem and reboot the host.


------------------------------------------------------------------------------------------------------------------------------
33) What r d agents will install, after adding an esx in VC server?

Vmware vcenter Agent


----------------------------------------------------------------------------------------------------------
34) What r d port No. for VMware management service?

8080, 8443 VMware vCenter 4 Management Web Services - HTTP and HTTPS


----------------------------------------------------------------------------------------------------------
35) What is d max No of VMs can run per host?

320

----------------------------------------------------------------------------------------------------------
36) What r all d files going to b create after a vm build?

.vmx, .vmfx, .vmsd, .vmdk (when start 3 more files are created --- .log, vswp, .nvram)

----------------------------------------------------------------------------------------------------------
37) What r d location of VC server log files?

C:\ProgramData\VMware\VMware VirtualCenter\Logs

---------------------------------------------------------------------------------------------------------
38) What r d necessary log files in ESX server?

esx server logs

VMWare ESX Server Logs

1) Vmkernel

a. Location: /var/log/

b. Filename: vmkernel

c. This log records information related to the vmkernel and virtual machines

2) Vmkernel Warnings

a. Location: /var/log/

b. Filename: vmkwarning

c. This log records information regarding virtual machine warnings

3) Vmkernel Summary

a. Location: /var/log/

b. Filename: vmksummary

c. This log records information used to determine uptime and availability statistics for ESX Server. This log is not easily readable by humans, import
into a spreadsheet or database for use.

d. For a summary of the statistics in an easily viewed file, see vmksummary.txt

4) ESX Server Boot Log

a. Location: /var/log

b. Filename: boot.log

c. Log file of all actions that occurred during the ESX server boot.

5) ESX Server Host Aagent Log

a. Location: /var/log/vmware/

b. Filename: hostd.log

c. Contains information on the agent that manages and configures the ESX Server host and its virtual machines (Search the file date/time stamps to find
the log file it is currently outputting to).

6) Service Console

a. Location: /var/log/

b. Filename: messages

c. Contain all general log messages used to troubleshoot virtual machines on ESX Server.

7) Web Access

a. Location: /var/log/vmware/webAccess

b. Filename: various files in this location

c. Various logs on Web access to the ESX Server.

8) Authentication Log

a. Location: /var/log/

b. Filename: secure

c. Contains the records of connections that require authentication, such as VMware daemons and actions initiated by the xinetd daemon.

9) VirtualCenter HA Agent Log

a. Location: /var/log/vmware/aam/

b. Filename: aam_config_util_*.log

c. These files contain information about the installation, configuration, and connections to other HA agents in the cluster.

10) VirtualCenter Agent

a. Location: /var/log/vmware/vpx

b. Filename: vpxa.log

c. Contains information on the agent that communicates with the VirtualCenter Server.

11) Virtual Machine Logs

a. Location: The same directory as the virtual machine’s configuration files are placed in.

b. FileName: vmware.log

c. Contains information when a virtual machine crashes or ends abnormally.



VirtualCenter Installation Logs

1) The following install logs are located in the %TEMP% directory of the user that installed VirtualCenter

a. vmlic.log i. Contains various test results for provided license file during the installation.

b. redist.log i. Contains MDAC/MCAD QFE rollup installation information

c. vmmsde.log i. Contains MSDE installation information

d. vmls.log i. The License server installation log.

e. vmosql.log i. The VirtualCenter database creation log file

f. vminst.log i. VirtualCenter installation log file

g. VCDatabaseUpgrade.log i. Results on upgrading the VC Database.

h. vmmsi.log i. The VI client installation log. Vpxd-0.log is a small log from the starting the client the first time.

Virtual Center Logs

1) Location:

a. C:\Documents and Settings\All Users\Application Data\VMware\VMware VirtualCenter\Logs

2) Name: vpxd-#.log (# is one digit, 0-9)

a. vpxd-index contains the # of the currently active log file

3) Logs rotate each time vpxd is started, and also when it reaches 5 MB in size

VI Client Logs

1) Location: User %TEMP%\vpx

2) Name: viclient-#.log (# is one digit, 0-9)

3) Logs rotate each time VI Client is started, and is should be used for client-specific diagnostics

Miscellaneous Logs

1) Core Dump

a. Location: %USERPROFILE%\Application Data\VMware

2) License Server Debug Log

a. Location: %SystemRoot%\Temp

b. Filename: lmgrd.log i. This file is overwritten each time the service starts

c. This file contains various information about the license file and server.

3) Web Access (Tomcat) Logs

a. Location: C:\Program Files\VMware\Infrastructure\VirtualCenter Server\tomcat\logs

b. Filename: various files

c. All the Tomcat logs are here


esx-console logs
sysboot-vmkernel-boot.log , sysboot-dmesg-boot.log, sysboot-vmkernel-late.log, sysboot-dmesg-late.og, sysboot.log

cd /vmfs/volumes/ESX-Storage-94-1/esxconsole-4c44398f-4238-b888-226e-001e0bcd236a/logs/

Core-dump location

cd vmfs/volumes/ESX-Storage-94-1/esxconsole-4c44398f-4238-b888-226e-001e0bcd236a/core-dumps


----------------------------------------------------------------------------------------------------------------------
39) What is ESXTOP command and how to use this command (with all the fields/options)?

Esxtop version 4.1.0
Secure mode Off

Esxtop: top for ESX

These single-character commands are available:

^L - redraw screen
space - update display
h or ? - help; show this text
q - quit

Interactive commands are:

fF Add or remove fields
oO Change the order of displayed fields
s Set the delay in seconds between updates
# Set the number of instances to display
W Write configuration file ~/.esxtop41rc
k Kill a world
e Expand/Rollup Cpu Statistics
V View only VM instances
L Change the length of the NAME field
l Limit display to a single group

Sort by:
U:%USED R:%RDY N:GID
Switch display:
c:cpu i:interrupt m:memory n:network
d:disk adapter u:disk device v:disk VM p:power mgmt

Hit any key to continue:


9:26:17pm up 9 days 45 min, 149 worlds; CPU load average: 0.02, 0.06, 0.06
PCPU USED(%): 2.5 32 38 0.3 19 0.5 0.3 0.4 2.2 57 0.0 0.0 0.3 24 0.3 50 AVG: 14
PCPU UTIL(%): 3.4 34 41 0.5 26 1.0 0.7 0.7 2.7 65 0.2 0.2 0.6 29 0.6 60 AVG: 16
CCPU(%): 0 us, 2 sy, 97 id, 0 wa ; cs/sec: 108

ID GID NAME NWLD %USED %RUN %SYS %WAIT %RDY %IDLE %OVRLP %CSTP %MLMTD %SWPWT
1 1 idle 16 1351.56 1497.67 0.00 0.00 122.22 0.00 0.94 0.00 0.00 0.00
59 59 Ubuntu 7 229.64 264.45 0.00 441.37 0.02 138.50 0.79 0.00 0.00 0.00
11 11 console 1 1.65 2.66 0.03 98.24 0.07 98.23 0.01 0.00 0.00 0.00
60 60 VMVXP-1 5 1.08 1.56 0.00 500.00 0.10 199.79 0.01 0.00 0.00 0.00
7 7 helper 77 0.04 0.05 0.00 7700.00 0.01 0.00 0.00 0.00 0.00 0.00
8 8 drivers 10 0.01 0.01 0.00 1000.00 0.00 0.00 0.00 0.00 0.00 0.00
56 56 vmkiscsid.4303 2 0.01 0.01 0.00 200.00 0.00 0.00 0.00 0.00 0.00 0.00
49 49 storageRM.4292 1 0.00 0.00 0.00 100.00 0.00 0.00 0.00 0.00 0.00 0.00
19 19 vmkapimod 9 0.00 0.00 0.00 900.00 0.00 0.00 0.00 0.00 0.00 0.00
2 2 system 7 0.00 0.00 0.00 700.00 0.00 0.00 0.00 0.00 0.00 0.00
9 9 vmotion 4 0.00 0.00 0.00 400.00 0.00 0.00 0.00 0.00 0.00 0.00
47 47 FT 1 0.00 0.00 0.00 100.00 0.00 0.00 0.00 0.00 0.00 0.00
48 48 vobd.4291 6 0.00 0.00 0.00 600.00 0.00 0.00 0.00 0.00 0.00 0.00
52 52 net-cdp.4300 1 0.00 0.00 0.00 100.00 0.00 0.00 0.00 0.00 0.00 0.00
53 53 net-lbt.4301 1 0.00 0.00 0.00 100.00 0.00 0.00 0.00 0.00 0.00 0.00
57 57 vmware-vmkauthd 1 0.00 0.00 0.00 100.00 0.00 0.00 0.00 0.00 0.00 0.00

The following optional switches, relevant to esxtop in batch mode, can be used:

a Shows all statistics and not what is specified in the default configuration file, if it exists.
b Runs esxtop in batch mode.
Loads a user-defined configuration file instead of the ~/.esxtop310rc default.
d Specifies the delay between statistics updates; the default is 5 seconds and the minimum is 2.
n Specified the number of statistics updates to capture before exiting.

For example, the following command would run esxtop in batch mode, updating all statistics to the file perfstats.csv every 10 seconds for 360 iterations (a
total of 60 minutes) before exiting:

esxtop -a -b -d 10 -n 360 > perfstats.csv

-------------------------------------------------------------------------------------------------
40) What is d location of esx dump file and how to read it?

Core-dump location

cd vmfs/volumes/ESX-Storage-94-1/esxconsole-4c44398f-4238-b888-226e-001e0bcd236a/core-dumps
-----------------------------------------------------------------------------------------------------
41) What id d location of the license file (*.LIC) in VC server and ESX server?

C:\ProgramData\VMware\VMware VirtualCenter\licenses\site\VMware VirtualCenter Server\4.0\4.1.0.2


----------------------------------------------------------------------------------------------------
42) What is d command to check the VMFS version and ESX version?

vmkfstools -P storageN
vmware -v and
vimsh -n -e 'hostsvc/hostsummary' | grep fullName OR
cat /proc/vmware/version

-----------------------------------------------------------------------------------------------------------
43) How to extend the OS drive of a guest OS (windows VM)

vmkfstools -X 50M /vmfs/volumes/Storage2/testvm/testvm.vmdk

vmkfstools -X 50M /vmfs/volumes/Storage2/testvm/testvm.vmdk

----------------------------------------------------------------------------------------------------------
44) What is d command to clone a VM?

vmware-vdiskmanager with option -r

# vmkfstools -i /vmfs/volumes/Datastore04/rhel5_test_template/rhel5_test_template.vmdk /vmfs/volumes/Datastore04/rhel5_test_clone/rhel5_test_clone.vmdk

-----------------------------------------------------------------------------------------------------------
45) What is d command to check all d virtual switch configuration details?

To configure networking from the ESX service console command line:
1.Ensure the network adapter you want to use is currently connected with the command:

[root@server root]# esxcfg-nics –l

The output appears similar to:

Name PCI Driver Link Speed Duplex Description
vmnic0 06:00.00 tg3 Up 1000Mbps Full Broadcom Corporation NetXtreme BCM5721 Gigabit Ethernet
vmnic1 07:00.00 tg3 Up 1000Mbps Full Broadcom Corporation NetXtreme BCM5721 Gigabit Ethernet

In the Link column, Up indicates that the network adapter is available and functioning.
2.List the current virtual switches with the command:

[root@server root]# esxcfg-vswitch –l

The output appears similar to:

Switch Name Num Ports Used Ports Configured Ports Uplinks
vSwitch0 32 3 32 vmnic0

PortGroup Name Internal ID VLAN ID Used Ports Uplinks
VM Network portgroup2 0 0 vmnic0

In the example output, there exists a virtual machine network named VM Network with no Service Console portgroup. For illustration, the proceeding steps show
you how to create a new virtual switch and place the service console port group on it.


3.Create a new virtual switch with the command:

[root@server root]# esxcfg-vswitch –a vSwitch1


4.Create the Service Console portgroup on this new virtual switch:

[root@server root]# esxcfg-vswitch –A “Service Console” vSwitch1

Because there is a space in the name (Service Console), you must enclose it in quotation marks.

Note: To create Service Consoles one at time, you may need to delete all previous settings. For more information, see Recreating Service Console Networking
from the command line (1000266).


5.Up-link vmnic1 to the new virtual switch with the command:

[root@server root]# esxcfg-vswitch –L vmnic1 vSwitch1


6.If you need to assign a VLAN, use the command:

[root@server root]# esxcfg-vswitch -v -p “Service Console” vSwitch0

where is the VLAN number. A zero here specifies no VLAN.


7.Verify the new virtual switch configuration with the command:

[root@server root]# esxcfg-vswitch –l

The output appears similar to:

Switch Name Num Ports Used Ports Configured Ports Uplinks
vSwitch0 32 3 32 vmnic0

PortGroup Name Internal ID VLAN ID Used Ports Uplinks
Service Console portgroup5 0 1 vmnic0

Switch Name Num Ports Used Ports Configured Ports Uplinks
vSwitch1 64 1 64 vmnic1

PortGroup Name Internal ID VLAN ID Used Ports Uplinks
Service Console portgroup14 0 1 vmnic1


8.Create the vswif (Service Console) interface. For example, run the command:

[root@server root]# esxcfg-vswif –a vswif0 –i 192.168.1.10 –n 255.255.255.0 –p “Service Console”
[‘Vnic’ warning] Generated New Mac address, 00:50:xx:xx:xx:xx for vswif0

Nothing to flush.


9.Verify the configuration with the command:

[root@esx]# esxcfg-vswif –l
Name Port Group IP Address Netmask Broadcast Enabled DHCP
v swif0 Service Console 192.168.1.10 255.255.255.0 192.168.1.255 true false



----------------------------------------------------------------------------------------------------------------------------------------------
46) What is d command to upgrade the FS fromVMFS2 to VMFS3?

The first thing that you will need to do to perform the upgrade is log into the ESX 3 host as root. Once logged in then you need to unload the ESX 3 VMFS
drivers that are currently loaded. The unloading of the VMFS drivers is for both VMFS 2 and VMFS 3. To perform this you need to run the commands below.

vmkload_mod -u vmfs2

vmkload_mod -u vmfs3

You then need to load a specific driver for ESX3 that is called the "ESX3 Auxiliary FS driver". The command below that loads this driver also includes the
switch to enable the upgrade mode contained within the driver.

vmkload_mod fsaux fsauxFunction=upgrade

The next step is to perform the upgrade on the VMFS2 volume. To do this, you need to make sure that there are no other hosts accessing the volume. This is
very important, as it will go pear shaped quickly if other servers try to access the volume during the upgrade process.

vmkfstools -T /vmfs/volumes/

Once the upgrade is completed, you need to check and confirm that the volume is vmfs3. You can do this by running the following command which is once again
another vmkfstools command.

vmkfstools -P /vmfs/volumes/

You should also confirm that all your files are ok by checking the file system. The commonly used list command for file systems at the service console is "ls
-l". If you have any more volumes to upgrade you may rinse and repeat the steps above until they are all done. Once all your volumes are upgraded you do
need to unload the "auxiliary driver" that we loaded before and reload the normal VMFS drivers. Two ways of doing this, one is to reboot and the other is to
run the commands below.

vmkload_mod -u fsaux

vmkload_mod vmfs2

vmkload_mod vmfs3

•ESX 3.0.0 is provided with 3.21 (initial release)
•ESX 3.5.0 is provided with 3.31
•vSphere (ESX 4.0) is provided with 3.33
•vSphere (ESX 4.1) is provided with 3.46



-------------------------------------------------------------------------------------------------------------------------------
47) What is RDM and what r all d File Systems (FS) it supports?



-------------------------------------------------------------------------------------------------------------------------------
48) What is SRM and how it works?

VMware vCenter Site Recovery Manager delivers advanced capabilities for disaster recovery management, non-disruptive testing and automated failover. VMware
vCenter Site Recovery Manager can manage failover from production datacenters to disaster recovery sites, as well as failover between two sites with active
workloads. Multiple sites can even recover into a single shared recovery site. Site Recovery Manager can also help with planned datacenter failovers such as
datacenter migrations.

Disaster Recovery Management

. Create and manage recovery plans directly from VMware vCenter Server.
. Discover and display virtual machines protected by storage replication using integrations certified by storage vendors.
. Extend recovery plans with custom scripts.
. Monitor availability of remote site and alert users of possible site failures.
. Store, view and export results of test and failover execution from VMware vCenter Server.
. Control access to recovery plans with granular role-based access controls.
. Leverage iSCSI, FibreChannel, or NFS-based storage replication solutions.
. Recover multiple sites into a single shared recovery site.
. Take advantage of the latest features and technologies included in VMware vSphere.

Non-Disruptive Testing

. Use storage snapshot capabilities to perform recovery tests without losing replicated data.
. Connect virtual machines to an existing isolated network for testing purposes.
. Automate execution of tests of recovery plans.
. Customize execution of recovery plans for testing scenarios.
. Automate cleanup of testing environments after completing tests.

Automated Failover

. Initiate recovery plan execution from VMware vCenter Server with a single button.
. Automate promotion of replicated datastores for recovery using adapters created by leading storage vendors for their replication platforms.
. Execute user-defined scripts and pauses during recovery.
. Reconfigure virtual machines’ IP addresses to match network configuration at failover site.
. Manage and monitor execution of recovery plans within VMware vCenter Server.

What’s New in vCenter Site Recovery Manager 4?

. Protect more of your environment with added support for NFS storage replication.
. Set up many-to-one failover using shared recovery sites.
. Leverage new features in vSphere.


-------------------------------------------------------------------------------------------------------------------------------
49) What is d series of H/W (virtual) used for VM’s virtual mother mother/main board?



-------------------------------------------------------------------------------------------------------------------------------
50) What r d date store path selections & what r d options available for network load balancing?

You can display information about paths by running vicfg-mpath with one of the following options:
. List all devices with their corresponding paths, state of the path, adapter type, and other information.
vicfg-mpath --list-paths
. Display a short listing of all paths.
vicfg-mpath --list-compact
. List all paths with adapter and device mappings.
vicfg-mpath --list-map

Managing Path Policies with esxcli

For each storage device managed by NMP (not PowerPath), an ESX/ESXi host uses a path selection policy. By
default, VMware supports the following path selection policies. If you have a third‐party PSP installed on your
host, its policy also appears on the list. The following path policies are supported by default:

Table 5-1. Supported Path Policies

Policy Description

VMW_PSP_FIXED The host always uses the preferred path to the disk when that path is available. If the host
cannot access the disk through the preferred path, it tries the alternative paths. If you use the

VMW_PSP_FIXED policy, use esxcli nmp fixed to set or get the preferred path

VMW_PSP_FIXED_AP Extends the VMW_PSP_FIXED functionality to active‐passive and ALUA mode arrays.

VMW_PSP_MRU The host uses a path to the disk until the path becomes unavailable. When the path becomes
unavailable, the host selects one of the alternative paths. The host does not revert back to the
original path when that path becomes available again. There is no preferred path setting with
the MRU policy. MRU is the default policy for active‐passive storage devices and is required
for those devices.

VMW_PSP_RR The host uses an automatic path selection algorithm rotating through all available paths. This
algorithm implements load balancing across all the available physical paths. Load balancing
is the process of spreading server I/O requests across all available host paths. The goal is to
optimize performance in terms of throughput (I/O per second, megabytes per second, or
response times).

Table 5-2. Path Policy Effects

Policy Active/Active Array Active/Passive Array
Most Recently Used Administrator action is required to fail
back after path failure.
Administrator action is required to fail back
after path failure.
Fixed VMkernel resumes using the preferred
path when connectivity is restored.
VMkernel attempts to resume using the
preferred path. This can cause path
thrashing or failure when another SP now
owns the LUN.
Round Robin No fail back. Next path in round robin scheduling is
selected.
=================================================================================
1) Explain about your production environment? How many cluster’s, ESX, Data Centers, H/w etc ? 
2) How does VMotion works? What’s the port number used for it?
ANS--> TCP port 8000 

3) Prerequisites for VMotion?
Ans-->
1)ESX Servers must be configured with VMkenerl ports enabled for vmotion and on the same network segment
2)ESX Servers must be managed by the same Virtual Center server
3)ESX Must have compatible CPUs
4)ESX Servers muct have consisten Networks and NEtwroks labels
5)The VMs must be stored on shared storage - iSCSI or FC SAN or NAS/NFS
6)The VMs can not use localcd/floppy or internal only vrtual switches on the ESX server

Check out http://www.vmware.com/pdf/vi3_35/esx_3/r35u2/vi3_35_25_u2_admin_guide.pdf for more information

4) How does HA works? Port number? How many host failure allowed and why? 
ANS--> Maximum allowed host failures within a HA cluster is 4. What happens if 4 hosts have failed and a 5th one also fails.
I have still enough free resources to start up the virtual machines on the remaining hosts. Will HA start these virtual machines from the 5th failed host on the remaining hosts? 
ANS) That depends. If you have admission control enabled, if there are any resource constraints some VM's may not restart. If you have admission control disabled, the VM's will get restarted on any host left in the cluster. However, that doesn't mean they will be functional. Make sure you have enough port groups configured on your vSwitch for your Virtual Machine port group to accommodate

Host Firewalls. On ESX/ESXi hosts, VMware HA needs and automatically opens the following firewall ports.
Incoming port: TCP/UDP 8042-8045
Outgoing port: TCP/UDP 2050-2250

5) What are active host / primary host in HA? Explain it?
ANS-->
When you add a host to a VMware HA cluster, an agent is uploaded to the host and configured to communicate
with other agents in the cluster. The first five hosts added to the cluster are designated as primary hosts, and
all subsequent hosts are designated as secondary hosts. The primary hosts maintain and replicate all cluster
state and are used to initiate failover actions. If a primary host is removed from the cluster, VMware HA
promotes another host to primary status.
Any host that joins the cluster must communicate with an existing primary host to complete its configuration
(except when you are adding the first host to the cluster). At least one primary host must be functional for
VMware HA to operate correctly. If all primary hosts are unavailable (not responding), no hosts can be
successfully configured for VMware HA.

One of the primary hosts is also designated as the active primary host and its responsibilities include:
n Deciding where to restart virtual machines.
n Keeping track of failed restart attempts.
n Determining when it is appropriate to keep trying to restart a virtual machine.
If the active primary host fails, another primary host replaces it.

6) Prerequisites for HA ?
First, for clusters enabled for VMware HA, all virtual machines and their configuration files must
reside on shared storage (Fibre Channel SAN, iSCSI SAN, or SAN iSCI NAS), because you need to
be able to power on the virtual machine on any host in the cluster.
Second, VMware HA monitors heartbeat between hosts on the console network for failure
detection. So, to have reliable failure detection for HA clusters, the console network should have
redundant network paths. That way, if a host's first network connection fails, the second
connection can broadcast heartbeats to other hosts.
Last, if you want to use DRS with HA for load balancing, the hosts in your cluster must be part of
a VMotion network. If the hosts are not in the VMotion network, however, DRS can still make
initial placement recommendations.

7) How do DRS works? Which technology used? What are the priority counts to migrate the VM’s? 
8) How does snap shot’s works? 
9) What are the files will be created while creating a VM and after powering on the VM? 
10) If the VMDK header file corrupt what will happen? How do you troubleshoot? 
11) Prerequisites VC, Update manager? 
12) Have you ever patched the ESX host? What are the steps involved in that? 
13) Have you ever installed an ESX host? What are the pre and post conversion steps involved in that? What would be the portions listed? What would be the max size of it? 
14) I turned on Maintenance mode in an ESX host, all the VM’s has been migrated to another host, but only one VM failed to migrate? What are the possible reasons? 
15) How will you turn start / stop a VM through command prompt? 
16) I have upgraded a VM from 4 to 8 GB RAM; it’s getting failed at 90% of powering on? How do you troubleshoot? 
17) Storage team provided the new LUN ID to you? How will you configure the LUN in VC? What would be the block size (say for 500 GB volume size)? 
18) I want to add a new VLAN to the production network? What are the steps involved in that? And how do you enable it? 
19) Explain about VCB? What it the minimum priority (*) to consolidate a machine? 
20) How VDR works? 
21) What’s the difference between Top and ESXTOP command? 
22) How will you check the network bandwidth utilization in an ESXS host through command prompt? 
23) How will you generate a report for list of ESX, VM’s, RAM and CPU used in your Vsphere environment? 
24) What the difference between connecting the ESX host through VC and Vsphere? What are the services involved in that? What are the port numbers’s used? 
25) How does FT works? Prerequisites? Port used? 
26) Can I VMotion between 2 different data centers? Why? 
27) Can I deploy a VM by template in different data centers ? 
28) I want to increase the system partition size (windows 2003 server- Guest OS) of a VM? How will you do it without any interruption to the end user? 
29) Which port number used while 2 ESX transfer the data in between? 
30) Unable to connect to a VC through Vsphere client? What could be the reason? How do you troubleshoot? 
31) Have you ever upgraded the ESX 3.5 to 4.0? How did you do it? 
32) What are the Vsphere 4.0, VC 4.0, ESX 4.0, VM 7.0 special features? 
33) What is AAM? Where is it used? How do you start or stop through command prompt?
ANS) VMware-aam = HA.
VMware purchased the HA technology from Legato, who originally coined it as "Automated Availability Manager".

34) Have you ever called VMWare support? Etc 

35) Explain about Vsphere Licensing? License server? 

36) How will you change the service console IP?
Note: ESX 4.0 Update 2 introduces a new tool that simplifies the process of creating or restoring networking in the ESX service console. For more information, see Configuring or restoring networking from the ESX service console using console-setup (1022078).

Changing settings from the physical or remote console connection
Changing the IP for the Service Console must be done from the physical console or through a remote console session. If you make changes through a network connection such as SSH, network connectivity to the Service Console disconnects because the Service Console's network interface changes.

1.Run this command to set the IP address:

[root@server root]# esxcfg-vswif -i -n vswif0

where 
is the IP address and is the subnet mask.

Note: In this example, vswif0 is the Service Console adapter that is the interface to which you are applying the IP address change.


2.Open the /etc/hosts file with a text editor and modify it so that it reflects the correct IP address and hostname.
3.To change the default gateway address and the hostname, edit the /etc/sysconfig/network file and change the GATEWAY and HOSTNAME parameters to the proper values.
4.For the changes to take place, restart the network service with the command:

[root@server root]# service network restart

Note: If you are required to edit the hostname, then you must reboot the host.

Note: This command breaks any current network connections to the Service Console, but virtual machines continue to have network connection. If the ESX host is managed by VirtualCenter or vCenter Server, you may have to remove and re-add the host to the inventory. For more information, see ESX not working properly in VirtualCenter after IP address change (1005633).
Note: Making changes to IP and DNS server settings can have a negative impact on the normal operation of ESX/ESXi, particularly in HA clustered environments. For more information, see Identifying issues with and setting up name resolution on ESX/ESXi Server (1003735).

Note: If the changed IP does not persist across a reboot, try deleting and recreating the Service Console vswif management interface. For more information, see Recreating Service Console networking from the command line (1000266).
Changing the hostname without rebooting
To dynamically change the hostname, run the command:

[root@server root]# hostname newname

Note: This command creates a temporary hostname change. This change is lost when the system is rebooted.

Changing the DNS server settings
To change the DNS server settings, update the nameserver IPs and search domain in the /etc/resolv.conf file.

Changing settings in VMware vSphere or Infrastructure Client
To change the hostname, domain, DNS servers, and default gateway in VMware vSphere or Infrastructure Client:

1.Highlight the ESX host and click the Configuration tab.
2.Click DNS and Routing.
3.Click Properties.
4.To change the hostname, domain, and DNS servers, click the DNS Configuration tab and enter the appropriate values.

Note: Disable VMware High Availability if you do not want virtual machines to failover during the hostname IP change.

5.To change the default gateway, click the Routing tab and enter the appropriate value.
6.Reboot the ESX host for the changes to take effect .
7.Reconnect the ESX host to vCenter Server with the new IP address.
Generating new certificates for the ESX host
The ESX host generates certificates the first time the system is started. Under certain circumstances, it might be required to force the host to generate new certificates. Typically new certificates only need to be generated if the hostname has been changed or the certificates have been deleted accidentally.

Each time you restart the vmware-hostd process, the mgmt-vmware script searches for existing certificate files ( rui.crt and rui.key). If the files cannot be found, new certificate files are generated.

To generate new certificates:

1.Put the host into Maintenance Mode.
2.In the directory /etc/vmware/ssl, back up any existing certificates by renaming them with these commands:

[root@server root]# mv /etc/vmware/ssl/rui.crt /etc/vmware/ssl/orig.rui.crt
[root@server root]# mv /etc/vmware/ssl/rui.key /etc/vmware/ssl/orig.rui.key

Note: If you are regenerating certificates because you accidentally deleted them, you do not have to rename them.

3.Reboot your host to allow it to begin using the new certificate, or restart the host services:

a.Restart hostd, using this command:

service mgmt-vmware restart

b.Restart vmkauthd, using this command:

service vmware-vmkauthd restart

4.Exit Maintenance Mode.
5.Confirm that the ESX host successfully generated new certificates by running this command and comparing the time stamps of the new certificate files with orig.rui.crt and orig.rui.key:

[root@server root]# ls -la /etc/vmware/ssl/rui*
Notes:

•Disable VMware High Availability if you do not want virtual machines to failover during the hostname IP change. If you are using vSphere 4.x you can just disable host monitoring in the HA settings.
•For related information, see Verifying ESX Server host networking configuration on the service console (1003796).
•You may be required to regenerate your SSL certificate. For more information, see Replacing or Regenerating an SSL Certificate for the Management Interface (1843).
•You are required to edit files on an ESX host. For more information, see Editing files on an ESX host using vi or nano (1020302).
•For information on replacing VirtualCenter Server ceritificates, see:
?Replacing VirtualCenter Server Certificates in Virtual Infrastructure 3
?Replacing VirtualCenter Server Certificates in vSphere 4
•The iSCSI Qualified Name used for iSCSI storage configuration is based on the hostname of the ESX host. If you change the hostname of the ESX host, ensure to review your iSCSI software initiator configuration. For more information on iSCSI troubleshooting, see Configuring and troubleshooting basic software iSCSI setup (1008083).
•For more information on changing the hostname, see Changing the name of an ESX host (1010821).

37) What’s the difference between ESX and ESXi?
38) What’s the difference between ESX 3.5 and ESX 4.0?

39) P2V Prt Number and Log file location?
TCP/IP Ports Required by VMware Converter
Table lists the ports Converter uses in the conversion process.
If your VirtualCenter Servers or ESX Servers are configured to listen on port 905, you will have to make
adjustments accordingly.
Communication Paths | Port
Converter application to remote physical machine | 445 and 139
Converter application to VirtualCenter Server | 902
Converter application to ESX Server 3.x | 902
Physical machine to VirtualCenter Server | 902
Physical machine to ESX Server 3.x | 902
Log File Locations:
UFAD logs:
%WINDIR%\Temp\vmware-temp\vmware-converter*
%WINDIR%\vmware-temp\vmware-converter* (in Windows NT)
Client logs:
%TEMP%\vmware-temp\vmware-client*

Send these in to support using File > Export Logs. For Converter Boot CD, map a network drive using the
network configuration tool (see Chapter 5, “Using the Converter Boot CD for Local Cold Cloning,” on page 37)
and use File > Export Logs.

40) Micro vMotion
41)
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Q: How is VMware more stable than, say, a new physical server?

A: The idealized hardware provided by VMware provides a consistent virtual hardware environment that increases that stability of your virtual machines independent of the underlying physical hardware.


Q: Is any installation method better than any other?

A: No. Whichever installation method you're comfortable with and that produces a good build is the one for you.

Q: I'm having problems with my installation. What should I do?

A: Ensure that the hardware you're loading ESX Server on is supported. The same goes for the configuration. If you are certain the hardware and configuration are supported, then run the vm-support script mentioned previously.

Q: Why does this chapter include only the graphical installer method?

A: It's the recommended installation method from VMware and one that many in the x86-world are the most comfortable with. If you wish to try it another way, VMware offers a very complete installation document covering the various installation methodologies.
Q: When I copy my virtual machine and try to run it on my network, I get hostname already exists and IP address already exists errors. I thought I could simply copy my virtual machine. What is the problem?

A: You can copy your virtual machine, which is why you're running into this problem. The copy is an exact copy. Thus, you need to change the hostname, IP address, and even the computer's SID (if it has one).

Q: Can I move my Gold Master to my other ESX Servers?

A: Yes, it's a recommended time-saver. If your ESX Servers share a LUN, that too is a way to access your Gold Master or your VMlibrary for that matter.

Q: Are there any limitations to the number of virtual machines I can run on my ESX Server?

A: Yes. Each ESX Server allows for only 80 virtual CPUs and 200 registered virtual machines.

Q: Can I take a virtual machine running on VMware Workstation or GSX and run it in ESX?

A: It depends. The process is not as simple as cutting and pasting. There is a specific import process required for migrating virtual machines from either Workstation or GSX into ESX. Access the following link for the exact instructions: http://www.vmware.com/pdf/mobility_guide.pdf.
Q: Do you need to tweak the settings of your virtual machines after you've built them?

A: No. VMware has configured the defaults of your build to suit most server loads. However, depending on the profile of your server and the resource intensiveness of the service it's providing, you may want to consider tweaking some of the default settings to better ensure service stability and reliability.

Q: Are there more advanced features than the ones detailed in this chapter?

A: Yes… a lot more.

Q: Is clustering more stable in VMware?

A: We find that the idealized hardware, in combination with VMware's improvements in clustering support, has made virtual clustering very stable.

Q: Can you Vmotion a cluster?

A: That depends on the cluster type and how it is configured. Clusters using Raw Device Mapping in virtual mode can be moved with Vmotion according to VMware documentation.
Q: Does VMware support NIC teaming?

A: Yes, and it's a very good idea to configure your ESX Server, especially if it's for production, with teamed NICs. This will provide hardware fault tolerance in case one NIC fails.

Q: How many physical NICs do I need on my ESX Server?

A: That depends on the number of virtual machines and the network traffic they produce. You should have a minimum of two: one for your Service Console and one dedicated to your virtual machines.

Q: If I'm building a cluster using Microsoft Clustering Service, what's the best configuration for my heartbeat NIC?

A:For a Cluster in a Box, create a VMnet that your nodes of your cluster can attach their heartbeat NICs.

Q: Can you attach virtual machines on any ESX Server to a VMnet?

A: No. Only virtual machines on the ESX Server that the VMnet resides can attach to it.
Q: Why should you pay for a p-to-v toll when there are a number of ways to do it for free?

A: If you don't have the time or inclination to learn the manual process or need the assurance of a vendor for your physical-to-virtual migrations, then a tool that comes with support is a very reasonable option.

Q: What takes the longest in the p-to-v process?

A: Transferring the data of the physical server into either an image file or the virtual server itself. That's why tweaking your network settings for optimal throughput is essential when p-to-v'ing a server.

Q: Can you create complete backups of your physical servers and then recover them into virtuals?

A: I've used NTBackup to back up Windows 2000 Professional and Windows XP, and created virtuals out of .bkf files. It works but there's a bit of futzing around with the virtual once it is running. Try it.

Q: What's the most essential part of creating a smooth migration plan?

A: Practice. No matter what the tool or process, practice it and learn its gotchas and the workarounds. No matter what method you use, there will be times when it won't go as planned. Practicing your p-to-v process on a number of physical platforms and disk configurations allows you to become more adept once you're doing it for real.
Q: Will my software vendor support my application in a VMware environment?

A: You'll need to contact your specific software or applications vendor to find out; however, an increasing number of software vendors support virtualized environments. Once you've migrated your application from a physical to virtual environment it's very easy to migrate back to a physical environment for vendor support. An excellent document provided by VMware can be found at the following link: www.vmware.com/pdf/ms_support_statement.pdf.

Q: What are the best enablers to help ensure our server consolidation is a success?

A: Engaging with the lines of business and application owners not only assists in attaining an actionable schedule, but also develops a highly collaborative environment that facilitates buy-in and support for your project. In addition it will be difficult to incorporate rationalization into your project unless you are working directly with the business or application owners.

Q: What tools do you recommend for a server consolidation or virtualization project?

A: It's imperative to have a robust and comprehensive tool for capacity planning, including historical data. This tool can be utilized in every phase of your project. Other tools to support the project include modeling tools used in test consolidation scenarios. Finally, you'll need to evaluate and document tools and processes for each technology you wish to consolidate. The migration tools will need to support all the platforms you wish to use in your migration scenarios.
Q: What is the VMlibrary?

A: The VMlibrary (/vmlib) is simply a directory on your ESX Server that lets you organize the tools and files you need to manage and maintain your virtual infrastructure,

Q: Can ISOs be shared between ESX Servers?

A: If you place your VMlibrary on a LUN that's shared amongst your ESX Servers, you can share your ISO images or anything else you place in your VMlibrary.

Q: Why is Vmotion so cool?

A: Try it…and then imagine the possibilities and applications. You'll be a convert soon enough.

Q: You mentioned that additional ISVs were creating management capabilities for virtual infrastructures in their products. Which ones?

A: Look at HP Insight Manager, Dell OpenManage, IBM Director, BMC's Patrol product line, Computer Associates' Unicenter, and many others.
Q: I can't add a new virtual hard drive to my virtual machine. What should I do?

A: You may not have the appropriate permissions to add virtual hardware to the VM, or the VM may be powered on and won't allow the addition of virtual hardware while powered on.

Q: I just created a new virtual machine and attached to an existing disk. Every time I power on the VM, I get a blue screen. What could the problem be?

A: Make sure the OS type that you selected when you created the VM matches the OS type installed on the virtual disk. For example, if you selected Windows 2003 Standard for the VM when you created it, but the existing virtual disk has Windows 2000 Standard installed, you'll probably encounter issues.

Q: I followed the directions for Active Directory authentication, and I still can't log in using an account and password in AD. What should I do?

A: Check the time on your ESX Server and Active Directory and make sure they're synced up. Kerberos is very sensitive to being out of sync and could reject credentials if the time is not within specific limits. You can also review the System event logs for clues.
Q: What is the most important aspect of deploying ESX Server and virtual machines?

A: The ability to provide service at least as good as that which you had with physical servers. With adherence to best practices, you should easily be able to provide this and exceed it by a phenomenal degree.

Q: ISOs have been mentioned in several of the chapters. Why are they so important?

A: Good administrators strive to never leave their chairs, cubes, or offices. If they do, they may just run into a user (we're kidding, of course). Having a library of ISOs can help you in this endeavor. In addition, they run a lot faster than regular CDs.

Q: What will happen if I deploy systems management software on the ESX Server itself?

A: If you're going to do this, make sure you allocate enough memory so that the application doesn't impact the performance of your ESX Server and thus your virtual machines. Also, use a system management package that is supported and test your installation on your ESX Server thoroughly. If you notice a degradation of performance, contact the systems management software vendor. The major vendors have instructions and best practices for deploying their products onto ESX Server.

Q: What is the most important best practice to follow?

A: The one that ensures your smooth evolution into a virtual infrastructure education. Learn every aspect of a virtual environment to the best of your ability. Be passionate about it and you'll reap the rewards. See the recommended reading list, troll the VMware Web site regularly, as well as other Web sites dedicated to virtualization such as p2v.net, vmguru.com, and virtual-strategy.com.
Q: Which version of VMware ESX Server supports Boot from SAN?

A: ESX Server 2.5 supports Boot from SAN but has the following limitations: ESX server had to be installed in boot from SAN mode, the HBA can only be used by the Service Console, LUN masking should be used to restrict other ESX servers from the boot LUN, the HBA of the boot LUN must be a QLogic HBA, and the boot LUN must be the lowest numbered LUN controlled by the storage processor.

Q: Where are log files for VMware ESX Server written to?

A: /var/logs/vmware

Q: What do you do if you forget the root password of the Service Console?

A: You will need to boot into single-user mode from the Service Console by selecting linux from the LILO boot menu and appending -s to your boot choice. This will boot the console into single-user mode and will allow you to use the passwd command to change the root user password.

Q: Why do I still see processes for my virtual machine when running the ps command on the Service Console even though my virtual machine is powered down?

A: If there is still a virtual console session running for your VM, you will still see processes associated with it for mouse, keyboard, and screen (MKS) even though it is powered off.

Q: I accidently unmounted the VMFS volume on my ESX Server. How can I re-mount the volume without re-booting

A: You can type mount t vmfs vmfs /vmfs
Q: What software is qualified for use with VMware 2.5.1?

A: Please see http://vmware.com/pdf/esx_backup_guide.pdf for an up-to-date list of software that's compatible with ESX.

Q: What SANs are compatible with ESX Server?

A: Please see http://vmware.com/pdf/esx_SAN_guide.pdf for details on ESX-to-SAN server compatibility.

Q: What are the certified backup tools for ESX?

A: Please see http://vmware.com/support/esx25/doc/backup_tools_links.html.

Q: Can I back up my entire virtual machine from the Service Console?

A: Yes, but it is not advised. The console services should be left alone to manage the entire virtual machine infrastructure. It's best that backups be performed by separating the applications and data from the operating systems because backups can become quite large very quickly. You should consider a backup of the environments that change frequently (data and applications) with an agent specifically designed to perform this function. A backup of those virtual disks that change infrequently and need VMFS formats should be backed up from the Service Console. These console-based backups should be performed in a powered-down or suspended approach (preferred), or a suspended environment using redo logs as an alternative. All backups performed from a systems console mode must be restored in an all-or-nothing approach. Recovery for a single file or directory can only be accomplished via a backup agent or from a backup to a SAN environment using a variety of different recovery/restoral techniques.
Q: I'm not able to connect to the Service Console over the network. What could the issue be?

A: You may have allocated the Service Console NIC to the VMkernel. Use vmkpcidivyi to reassign the NIC to the Service Console.

Q: I have a virtual machine that did not start up correctly, but now I can't power it down from the MUI or Virtual Center. How can I get this VM to shut down?

A: You can use the vmware-cmd utility to force a hard power down. The following syntax should work:

vmware-cmd /path-to-vm/vm-directory/vm.vmx stop hard

Q: I find using commands to be very difficult. Why can't I use X Windows on the Service Console?

A: You actually could run the X Windows system on the Service Console, but it will eat up valuable resources that are needed by the system to manage all the processes related to Virtualization. VMware specifically says not to run X Windows on the Service Console. So, it's best to just buck up and deal with it.

Q: Is there a way to mount the vmfs volumes if they accidentally get unmounted without having to reboot?

A: Yes. You can run mountt vmfs vmfs /vmfs.

Q: How do I check the speed and duplex setting of the Service Console NIC? Also, how do I change it if needed?

A: You'll need to cat out the eth0.info file for your type of adapter. This file can be found at /proc/net/type-of-nic/eth0.info. To give you an example, our server has an Intel Pro 100 Nic for the Service Console, so for us to find the speed and duplex information we would type: cat /proc/net/PRO_LAN_Adapters/eth0.info.
Q: How long has Xen been around?

A: Since 2004, and they're located in Palo Alto, California. Hmm…what other virtualization company is in Palo Alto?

Q: What is a hypervisor?

A: In VMware parlance, it's the virtualization layer.

Q: Why did VMware limit its beta of ESX Server 3.0 to so few?

A: Good question…We don't know, and we hope that VMware's future beta programs are opened up to a larger audience.

Q: If I can't get a SAN, will local storage with a RAID device be sufficient?

A: Absolutely. You won't get some of the cooler tools like VMotion, but being virtual on local storage is better than remaining physical.
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Please find the latest vmware interview question

http://www.vmwarearena.com/2013/03/vmware-interview-questions-history-of.html


http://www.vmwarearena.com/2012/10/difference-between-vsphere-41-and.html


http://www.vmwarearena.com/2012/10/difference-between-esx-35-esx-40.html


http://www.vmwarearena.com/2012/08/vmware-interview-questions-answers.html


http://www.vmwarearena.com/2012/08/vmware-interview-questions-and-answers.html


http://www.vmwarearena.com/2012/07/vmware-interview-questions-and-answers_20.html

http://www.vmwarearena.com/2012/07/vmware-interview-questions-and-answers.html


http://www.vmwarearena.com/2012/07/vmware-interview-questions-svmotion.html


http://www.vmwarearena.com/2012/07/vmware-interview-questions-vmotion.html
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VMWare interview questions and answers

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