VMWare Interview Questions and Answers | Top 281 Questions

Top 281 Frequently Asked VMWare Interview Questions

1. What do you understand by VMKernel and why it is important?
Answer: VMkernel is defined as a virtualization interface between an ESXi host and the Virtual Machine which helps in storing the VMs. It is responsible for allocating all the available resources to VMs such as memory, CPU, Storage etc, of the ESXi host. It also controls special services such as vMotion, Fault tolerance, NFS, traffic management and iSCSI. For accessing these services, VMkernel port can be configured on the ESXi server by making use of a standard or distributed vSwitch. Without VMkernel, hosted VMs are not capable of communicating with the ESXi server.

2. What are the hypervisor and its types?
Answer: A hypervisor is defined as a virtualization layer that helps in enabling the multiple operating systems for sharing a single hardware host. Each operating system is allocated the physical resources such as CPU, storage, memory, etc by the host. There are basically two types of hypervisors which are as follows:

  • Hosted hypervisor (works as application i.e. VMware Workstation)
  • Bare-metal (is virtualization software i.e. VMvisor).

3. What do you understand by the term Virtualization?
Answer: It is defined as the process which helps in creating virtual versions of the physical components i.e. Network Devices, Servers, and Storage Devices on a physical host termed as virtualization. Virtualization lets you run the multiple virtual machines on a single physical machine which is termed as ESXi host.

4. What is VMware Tools?
Answer: VMware Tools is defined as a suite of utilities that we use to install in the operating system of a virtual machine. VMware Tools helps in enhancing the performance of a virtual machine. You can install VMware Tools on Windows as well as Linux Operating Systems. VMware Tools has various advantages such as the faster graphics performance, synchronization of Clock in VM, improved mouse performance, Copy and paste text & files, and many more.

5. What is Hardware Version?
Answer: The hardware version of a virtual machine helps in reflecting the virtual machine  that support the virtual hardware features. These features are corresponded to the physical hardware which is available on the ESXi host on which we are capable of creating the virtual machine. Virtual hardware features include BIOS and EFI, maximum memory configuration, available virtual PCI slots, maximum number of CPUs, and other characteristics typical to hardware. You can easily upgrade the Hardware version of Virtual Machine but it requires the virtual machine to be powered off.

6. What are the Memory Management Techniques in VMware?
Answer: ESXi uses 4 types of Memory management Techniques to reclaim memory when physical memory is not available. Below are 4 types:
Transparent Page Sharing (TPS):
Transparent Page Sharing is used when multiple virtual machines are making use of the same operating system. So, at that time ESXi will check for the identical memory pages and it will be keeping a single copy of the identical pages by removing the redundant pages. This technique will help the ESXi for reclaiming the memory easily. It is enabled by default.
Memory Ballooning:
Ballooning is a dynamic memory reclamation technique used when ESXi is running out of memory and it uses balloon drivers to reclaim memory from VMs. Balloon driver is itself included in the VMware Tools which is installed in the VM.
Memory Compression:
When the Ballooning isn’t able to reclaim the memory then ESXi makes use of the Memory Compression. It helps in compressing and storing the memory in a cache in host’s main memory. Memory compression takes place when we find that the page’s compression ratio is greater than 50%. It gets enabled by default.
Hypervisor based memory swapping:
When the TPS, Ballooning and Memory compression are not in working conditions then the ESXi makes use of the Memory Swapping in which ESXi is used to swap guest VMs memory to the swap file which is used to make the physical memory available.

7. What is Standard Switch?
Answer: A vSphere Standard Switch is very similar to a physical Ethernet switch. You use standard switches for providing network connectivity to the virtual machines and hosts. A standard switch is capable of bridging the traffic internally between links to external networks and the virtual machines in the same VLAN. In order to provide the network connectivity to the virtual machines and the hosts, you can connect to the physical NICs of the hosts for up linking the ports on the standard switch.

8. What is Distributed Switch?
Answer: A vSphere distributed switch function is defined as a single switch across all the associated hosts. This is enabling you for setting the network configurations that is spanning across all the member hosts which allows the virtual machines for maintaining the consistent network configuration as they migrate across multiple hosts. In Standard Switch you need to create Port Groups on each host but in case of Distributed Switch you only have to create port groups once and it will be applied to all hosts.

9. What is Traffic Shaping?
Answer: ESXi allows you to shape the incoming and outgoing traffic on Port Groups. A traffic shaping policy is the policy which is defined by various characteristics such as: average bandwidth, peak bandwidth, and burst size. Standard switch only supports the outbound traffic shaping.

10. What is Port Group?
Answer: Port Groups aggregates multiple ports of virtual machines. Each port group in this VMware gets identified by a network label which is unique for the current host. Network labels are used in making the virtual machine configuration portable across the various hosts. You can either create a VMkernel port group or VM port group based on requirements. You can set VLAN IDs on Port Groups.

11. What are the Network Adapter Types in VMware?
Answer: When we add Network Adapter to the VM, we have the option to choose from multiple network adapters for better performance. So below is the Network Adapter Types available in VMware:
It is termed as an Emulated version of the Intel 82545EM Gigabit Ethernet NIC with the drivers that are available in the most newer guest operating systems which also include the Linux versions 2.4.19 and Windows XP and later.
It is an Emulated version of the Intel 82574 Gigabit Ethernet NIC. E1000E is defined as the default adapter for the Windows Server 2012 and Windows 8.
It is optimized for performance in a virtual machine and has no physical counterpart. Because operating system vendors usually do not provide you with the built-in drivers and one must install the VMware Tools for the VMXNET network adapter to make it available. If VMware Tools are not installed in the Guest Operating system this adapter will not be visible.
VMXNET 2 (Enhanced):
It is based on the VMXNET adapter but provides high-performance features commonly used on modern networks such as jumbo frames and hardware offloads. VMXNET 2 (Enhanced) is defined as the network adapter type in VMware which is available only for some guest operating systems on the ESX/ESXi 3.5 and later.
A paravirtualized NIC is designed for performance. VMXNET 3 is defined as the network adapter type in VMware which offers all the features that are available in VMXNET 2 and also add several new features such as MSI/MSI-X interrupt delivery, IPv6 offloads, multi queue support. VMXNET is the network adapter type in VMware 3 which is not related to VMXNET or VMXNET 2.
SR-IOV passthrough:
It is the representation of a virtual function (VF) on a physical NIC with SR-IOV support. The physical adapter and the virtual machine are usually used for exchanging the data without making use of the VMkernel as an intermediary. This network adapter type is best suited for the virtual machines where latency can cause the failure or which requires more CPU resources. SR-IOV passthrough is the network adapter type which is available in Windows Server 2008 R2 with SP2 and ESXi 6.0 and later for guest operating systems.

12. What are Security Policies available in Standard and Distributed Switch?
Answer: Below are 3 Security Policies available in vSphere Standard as well as Distributed Switch:
Promiscuous Mode: It is used mostly when you want to capture or sniff all the packets coming on the same port group. There are 2 options available: Accept and Reject. When it is set to Accept, you can monitor or capture all the network packets on the vSphere standard switch that are allowed under the VLAN policy for the port group that the adapter is connected to, but when it is set to Reject there is no impact on the packets sent or received.
MAC Address Changes: It usually works on the MAC Address of the Virtual Machines. There are 2 options available: Accept and Reject. If you set it to Accept then, if the VM’s MAC address is changed from the original MAC Address assigned, VM will be able to send and receive network packets. But when it is set to Reject then, if the VM’s MAC Address is changed from the original MAC Address then VM will not able to send or receive network packets.
Forged Transmits: It also works the same as MAC Address changes in which MAC Address of the VM is compared by ESXi with the Source MAC Address. There are 2 options available: Accept and Reject. When it is set to Accept no filtering is performed and all outbound frames are passed but when it is set to reject any outbound frame with a source MAC address is the address which is different from the one currently setting on the adapter.

13. What is vMotion?
Answer: vMotion allows you to migrate virtual machines from one physical ESXi host to another ESXi host without downtime. In vMotion only virtual machines will be migrated from one host to another and the storage stays at the same place. vMotion is the most used feature in VMware vSphere. This is the capability which is possible across the Clusters, vSwitches, and even Clouds. It is also called live migration.

14. What is Storage vMotion?
Answer: Storage vMotion allows you to migrate virtual machine disks from one datastore to another. It means that you can easily migrate your virtual machine from one storage to another without downtime. By Storage vMotion you can transform virtual disks from Thick-Provisioned Lazy Zeroed to Thin-Provisioned or the reverse.

15. What are DRS?
Answer: DRS is also called as Distributed Resource Scheduler. DRS works on the cluster level. DRS is the most useful feature when you have heavy workloads. DRS will continuously monitor the load on the ESXi hosts and if the load increases then it will migrate VMs from one host to another to balance the load on the cluster. There are 3 types of modes available in DRS: Fully Automated, Partially Automated and Manual.

16. What is SDRS?
Answer: SDRS is called Storage DRS. SDRS works on the datastore cluster where multiple data stores are added into a single cluster. Storage Distributed Resource Scheduler allows you to manage the aggregated resources of a datastore cluster. When Storage Distributed Resource Scheduler gets enabled then it provides the recommendations for virtual machine disk placement and migration for balancing the space and Input/output resources across the data stores which are in the cluster.

17. What is High Availability?
Answer: High Availability is referred to as HA in VMware. HA works on the Cluster level. VMware HA provides us high availability for the virtual machines by pooling them and the hosts they reside on into a cluster. Hosts in the cluster are getting monitored and in the failure event the virtual machines on a failed host are restarted on the alternating hosts.

18. What is Fault Tolerance?
Answer: Fault Tolerance is referred to as FT in VMware. FT works on the VM level. VMware Fault Tolerance provides us with continuous availability for the virtual machines by creating and maintaining a Secondary VM which is identical and available for the replacement of the Primary VM in the event of a failover situation. You can enable the Fault Tolerance for most mission critical virtual machines.

19. What is EVC?
Answer: EVC is known as Enhanced vMotion Compatibility. EVC is used when you have multiple CPU family hosts in the same cluster. Enhanced vMotion Compatibility feature is the feature which helps and ensures the vMotion compatibility for the hosts in a cluster. Enhanced vMotion Compatibility also ensures that all hosts in a cluster present the same CPU feature setting for the virtual machines even if the actual CPUs on the hosts are different. By making use of Enhanced vMotion Compatibility it prevents the migrations of vMotion from failing because of the incompatible CPUs.

20. What is VCHA?
Answer: VCHA is the new feature announced in vSphere 6.5. VCHA is referred to as vCenter High Availability. VCHA provides high availability for the vCenter Server by the creation of the secondary copy of the vCenter Server. So in case your primary vCenter fails, a secondary vCenter will take over it and you have your vCenter Server running.

21. What is a Resource Pool?
Answer: Resource pools allow you to delegate control over resources of a host which are CPU and Memory. You can create a Resource Pool and assign an amount of resources to the virtual machines inside the resource pool. A resource pool is defined as the pool which contains virtual machines, child resource pools or both. You can create multiple resource pools based on your requirement.

22. What is vApp?
Answer: A vApp is a logical container like a resource pool and can contain one or more virtual machines. In addition, a vApp is also an application which shares some functionality with virtual machines. A vApp is the application which has power on and power off and can also be cloned. You can even export vApp.

23. What is Host Profiles?
Answer: Host Profile allows you to create and maintain consistent configurations among ESXi Hosts. You can create a Host Profile from one Host and attach it to another host to maintain the same configuration and make them compliant. It helps you to avoid the error and misconfiguration in larger environments.

24. What is Hot Add?
Answer: Hot Add is a more useful feature where you can add or increase the CPU and Memory of the Virtual Machine while it is running. First you have to enable Hot Add CPU and Memory for the Virtual Machine when you create Virtual Machine.

25. What is VUM?
Answer: VUM is defined as the VMware Update Manager. VUM is used to Upgrade and Patch the ESXi Hosts. With the help of VUM we can also upgrade the virtual appliances and VMware Tools.

26. What is vCenter Converter?
Answer: vCenter Converter is used to convert Physical Servers into virtual machines. By using vCenter Converter you can easily convert without much hassle of creating vm and copying data. Conversion Process is called P2V.

27. What is the Content Library in VMware?
Answer: Content Library is the container you create to store different objects such as Template, ISO, Config Files, and Scripts etc. It allows you to share the templates and files across the multiple vCenter Server instances in the different locations or same locations which results in compliance, consistency, efficiency, and automation in deploying the workloads at scale.

28. What are the Two Types of Content Library available in VMware?
Answer: There are basically two types of content libraries:
Local Content Library: You use a local library to store items in a single vCenter Server instance. You are capable of publishing the local library so that the users from other vCenter Server systems can subscribe to it. When you publish a content library externally, you can configure a password for authentication.
Subscribed Content Library: You subscribe to a published library by creating a subscribed library. You are capable of creating the subscribed library in the same vCenter Server instance where the published library is or in a different vCenter Server system. In the Create Library wizard you have the option for downloading all the contents which is present in the published library immediately after the subscribed library has been created or for downloading only metadata for the items from the published library and to later download the full content of only the items you intend to use.

29. What is Cold Migration?
Answer: Cold Migration is when you want to migrate powered off or suspended virtual machines. For performing a cold migration, you have an option of moving the virtual machines manually or setting up a scheduled task.

30. What is Hot Migration?
Answer: Hot Migration is when you migrate running power on virtual machines. vMotion is also referred to as “live migration” or “hot migration.”

31. How vSphere Licensing Works?
Answer: vSphere is licensed on a per-processor basis. Each physical processor in a server needs to have at least one processor license key which is assigned to run the vSphere. There are as such no limits on the Number of the Virtual Machines and Physical Resources.

32. Which License editions are available in vSphere 6.7?
Answer: Below are the editions available in vSphere 6.7 :

  • vSphere Standard
  • vSphere Enterprise Plus
  • vSphere with Operations Manager Enterprise Plus
  • vSphere Platinum

You also have option for Smaller Environment:

  • vSphere Essentials Kit
  • vSphere Essentials Plus kit

You also have option for Remote Office and Branch Offices:

  • vSphere Remote Office Branch Office Standard
  • vSphere Remote Office Branch Office Advanced

33. Which are Editions available in vCenter Server?
Answer: vCenter Server comes in below 3 editions:

  • vCenter Server For Essentials (For Essential Kits with up to 3 ESXi Hosts supported)
  • vCenter Server Foundation (Up to 4 ESXi Hosts supported.)
  • vCenter Server Standard (Unlimited Number of ESXi Hosts supported.)

34. What is vSphere Replication?
Answer: VMware vSphere Replication is defined as a hypervisor-based, asynchronous replication solution for the vSphere virtual machines. By making use of the vSphere Replication we can easily replicate virtual machines from one site to the other.

35. What is SRM?
Answer: SRM is referred to as Site Recovery Manager. SRM is defined as a business continuity and disaster recovery solution that helps us for the testing, planning, and running of the recovery of the virtual machines between a protected vCenter Server site and a recovery vCenter Server site. We are able to configure SRM with vSphere Replication or with Array Based Replication.

36. What is VMware NSX?
Answer: NSX is a Network Virtualization by VMware which provides complete virtualization of networking components in datacenter using software. NSX Data Center helps in providing a complete set of logical networking services and elements, including the load balancing, VPN, quality of service (QoS), logical switching, routing, firewalling, and monitoring. These services get provisioned through any cloud management platform in virtual networks leveraging the NSX Data Center APIs. Virtual networks get deployed over any existing networking hardware non-disruptively. NSX is the main component of Software Defined Data Center (SDDC).

37. What are Key Features of VMware NSX?
Answer: Below are the Key Features of NSX which are as follows:

  • Switching
  • Routing
  • Distributed Firewalling
  • Load Balancing
  • VPN
  • NSX Gateway
  • Multi Site Networking

38. What are the ways of Installing ESXi?
Answer: The ways of installing ESXi are as follows:

  • Interactive ESXi installation
  • Scripted ESXi installation
  • Auto Deploy ESXi installation
  • Customizing installations with ESXi Image Builder CLI and many more.

39. What are the different types of virtualization?
Answer: There are 5 basic types of virtualization.

  • Server virtualization: It helps in consolidating the physical server and multiple OS that is running on a single server.
  • Network Virtualization: It helps in providing the complete reproduction into a software-defined network of the physical network.
  • Storage Virtualization: It helps in providing an abstraction layer for the physical storage resources to manage and optimize in the virtual deployment.
  • Application Virtualization: It helps in increased mobility of applications and allows the migration of VMs from a host to another with minimal downtime.
  • Desktop Virtualization: The virtualization desktop helps in reducing the cost and increasing the service.

40. Why is virtualization needed?
Answer: Virtualization reduces the number of physical servers, reducing the energy needed to power and funky them. It saves time. It is also a lot quicker to deploy a virtual machine than to deploy a brand new physical server. Reduces desktop management headaches.

41. How will virtualization work?
Answer: Golf stroke multiple VMs on one pc permits many operating systems and applications to run on only 1 physical server or host. A skinny layer of package referred to as a “hypervisor” decouples the virtual machines from the host and dynamically allocate computing resources to every virtual machine PRN.

42. What is VMware?
Answer: VMware, Inc. is an American company that provides cloud and virtualization software and services and claims to be the first to successfully virtualize the x86 architecture commercially. It was founded in 1998. VMware is based in Palo Alto, California.

43. What is VMware FT?
Answer: FT simply means the Fault Tolerance which is a very prominent component of the VMware vSphere. It helps in providing the continuous availability for VMs when an ESXi host fails. It supports up to 4 vCPUs and 64 GB memory. Fault Tolerance is bandwidth intensive and 10GB NIC is usually recommended for the configuration of it. It helps in creating a complete copy of an entire VM such as storing, computing, and memory.

44. How many vCPUs can be used for a VM in FT?
Answer: In vSphere 6.0, we can use upto 4 vCPUs and the RAM of 64 GB can be used.

45. What is the name of the technology used by VMware FT?
Answer: vLockstep technology is used by the VMware Fault Tolerance.

46. What is Fault Tolerant Logging?
Answer: The communication between the two ESXi hosts is termed as the Fault Tolerance logging when the Fault Tolerance is configured between them. The prerequisite of configuring FT is to configure VMKernel port.

47. Will the FT work if vCenter Server goes down?
Answer: vCenter server is only required to enable the Fault Tolerance on a VM. Once it gets configured, vCenter is not required to be online for the Fault Tolerance to work. Fault Tolerance failover between primary and secondary will take place even if the vCenter is down.

48. What is the main difference between VMware HA and FT?
Answer: The main differences between VMware HA and VMware FT are: VMware HA gets enabled per cluster whereas the VMware FT gets enabled per VM. In VMware HA, VMs will be re-started and powered-on onto another host in case of a host failure whereas in VMware FT there is no downtime because the second copy will be activated in case of the host failure.

49. What do you mean by NFS?
Answer: NFS means the Network File System which is defined as a file-sharing protocol that helps in making use of a communication bridge between ESXi hosts and NAS (Network-attached storage) devices over a Transfer Control Protocol/Internet Protocol network. It is also able to hold the ISO images, templates and virtual machines files.

50. What do you mean by RDM?
Answer: Raw device mapping (RDM) is a mapping file located in VMFS volume and acts as a proxy for the raw physical storage device. It helps in allowing the virtual machine for reading and writing from the storage and it also contains metadata for managing and redirecting disk to the physical device. By making use of the raw device mapping we can make use of the file system, Vmotion and can also be capable of adding raw LUNs to the virtual machine.

51. What do you understand from the term virtual networking?
Answer: A network of VMs connected logically with each other which runs on a physical server is called virtual networking.

52. What is Hardware virtualization & advantages of hardware Virtualization?
Answer: Transforming Hardware resources into software layers is called Hardware virtualization. Using hardware virtualization we can run multiple operating systems concurrently on a piece of hardware.So we are capable of reducing the Hardware Resources Save Power, cooling, Space. Provides high availability to Virtual Machines.

53. What is VM Monitoring status?
Answer: HA usually monitors ESX hosts and reboot the virtual machine in the failed hosts and in case of host isolation one needs the HA to monitor the Virtual machine failures also. Here is the feature known as the VM monitoring status which is the part of the HA settings.VM monitoring is used to restart the virtual machine if the VMware tools heartbeat isn’t able to receive in the specified time by making use of the Monitoring sensitivity.

54. What is vSS?
Answer: vSS simply means the Virtual Standard Switch which is responsible for communication of VMs hosted on a single physical host. It works like a physical switch and helps in automatically detecting a VM which wants to communicate with another VM on the same physical server.

55. What is vDS?
Answer: vDS simply means that Virtual Distributed Switch which acts as a single switch in a whole virtual environment and is also responsible for providing the central provisioning, administration, and monitoring of the virtual network.

56. How many standard ports are maximum available per host?
Answer: There are 4096 ports available per host that are either in a distributed switch or standard switch.

57. What are the main benefits of distributed switch (vDS)?
Answer: vDS can provide:

  • Central administration for a data center
  • Central provision, and
  • Monitoring

58. What is the VMKernal adapter and why is it used?
Answer: VMKernel adapter is the adapter which is used to provide network connectivity to the ESXi host for handling the network traffic for IP Storage, vMotion, NAS, Fault Tolerance, and vSAN. For each type of traffic such as vSAN, vMotion etc. separating the VMKernel an adapter should be created and configured.

59. What is the main use of port groups in data center virtualization?
Answer: You can segregate the network traffic by using port groups such as vMotion, FT, management traffic etc.

60. What three port groups are configured in ESXi networking?

  • Virtual Machine Port Group – it is the port group which is used for the Virtual Machine Network.
  • Service Console Port Group – it is the port group which is used for Service Console Communications.
  • VMKernel Port Group – it is the port which is utilized for iSCSI, VMotion, NFS Communications.

61. What is VLAN and why is it used in virtual networking?
Answer: A logical configuration on the switch port to segment the IP Traffic where each segment cannot communicate with other segments without proper mentioning of rules is called VLAN and every VLAN has a number called VLAN ID.

62. What is VLAN Tagging?
Answer: The practice of inserting VLAN ID into a packet header to identify which VLAN packet it belongs to is called VLAN tagging.

63. What are the three network security policies/modes on vSwitch?
●Promiscuous mode
●MAC address change
●Forged transmits

64. What is promiscuous mode on vSwitch?
Answer: The default mode is reject. If Accept is selected, VM will receive all traffic port groups via vSwitch.

65. What MAC address changes network policy?
Answer: The default mode of this policy is Accept. If the reject gets selected then a host will accept the requests for changing the effective MAC address.

66. What is forged transmits network policy?
Answer: The default mode is Accept. If the reject gets selected then a host will not be comparing the effective MAC address and source which gets transmitted from a VM vCenter Server.

67. What are the main components of vCenter Server architecture?
Answer: There are three main components of vCenter Server architecture.

  • vSphere Client and Web Client: This is the component which is a user interface component.
  • vCenter Server database: It is the embedded PostgreSQL or SQL server for storing the security roles, inventory, resource pools etc
  • SSO: It is the component which is a security domain in a virtual environment.

68. What are PSC and its components?
Answer: PSC stands for Platform Services Controller, first introduced in version 6 of VMware vSphere which handles infrastructure security functions. It has three main components.

  • Single Sign-On (SSO)
  • VMware Certificate Authority (CA)
  • Licensing service

69. What are the two main deploying methods of PSC?
Answer: You can install PSC in two ways:

  • Embedded
  • Centralized

70. What are different types of vCenter Server deployment?
Answer: It has two deployment types.

  • Embedded Deployment
  • External deployment

71. What is vRealize Operation (vROP)?
Answer: vRealize Operation helps in providing the operation dashboards for the capacity optimization, performance analytics and monitors the virtual environment.

72. What is the basic security step to secure vCenter Server and users?
Answer: Authenticate vCenter Server with Active Directory. By using this we can assign specific roles to users and can also manage the virtual environment in an efficient way.
Virtual Storage (Datastore)

73. What do you mean by datastore?
Answer: Datastore is defined as a storage location where the virtual machine files get stored and accessed. Datastore is based on a file system which is called VMFS, NFS.

74. What is the .vmx file?
Answer: It is the configuration file of VM.

75. What information .nvram files store?
Answer: It stores BIOS related information of VM.

76. What .vmdk file does and uses?
Answer: Vmdk is defined as a VM disk file and helps in storing the data of a VM. The size of the file can be up to 62 Tera Byte in vSphere 6.0 version.

77. How many disk types are in VMware?
Answer: There are three disk types in vSphere.

  • Thick Provisioned Lazy Zeroes: In this disk format every virtual disk gets created by default. Physical space is allocated to a VMware when a virtual disk gets created. It can’t be converted to a thin disk.
  • Thick Provision Eager Zeroes: This is the disk type in the vSphere which is used in the VMware Fault Tolerance. All the required disk spaces are allocated to a VM at time of the creation. It takes more time for creating a virtual disk and comparing to other disk formats.
  • Thin provision: It provides an on-demand allocation of disk space to a VM. When the size of data grows, the size of a disk will also grow automatically. Storage capacity utilization with this can be up to 100%.

78. What is Storage vMotion?
Answer: Storage vMotion is the vMotion which is similar to the traditional vMotion. In Storage vMotion, a virtual disk of a VM is moved from one datastore to another. During the Storage vMotion, the virtual thick provisioning disk can be transformed to the thin provisioned disk.

79. What is the VM Hardware version for vSphere 6.0?
Answer: Version 11

80. What VM hardware version for vSphere 6.5?
Answer: Version 13

81. In which version of vSphere PSC was introduced?
Answer: Platform Services Controller (PSC) is introduced in vSphere 6.0. vSphere 6.0 version is also termed as Virtual hardware version 11.

82. How many maximum hosts can manage a vCenter Server in vSphere 6.0?
Answer: In vSphere 6.0, a single vCenter Server has the ability to manage up to 1000 hosts either in vCenter Appliance (vCSA) or in Windows.

83. How many hosts can be managed by a cluster in vSphere 6.0?
Answer: A single cluster has the ability of managing maximum of 64 hosts.

84. How can maximum VMs be managed by a single cluster?
Answer: A single cluster has the ability of managing the maximum of 8000 VMs.

85. What is VVol?
Answer: Virtual Volume is defined as a new VM disk management concept which is introduced in vSphere 6.0 that enables an array-based operations at the virtual disk level. Virtual Volume gets automatically created for a VM when a virtual disk is created in a virtual environment.

86. How many licensing options exists for vSphere 6.0?
Answer: There are three licensing options for vSphere 6.0:

  • Standard Edition: Contains 1 vCenter Server Standard license upto 2 vCPUs for Fault Tolerance, vMotion, Storage vMotion, HA, VVols etc.
  • Enterprise Edition: Same as Standard Edition but additionally contains APIs for Array Integration and Multipathing, DRS, and DPM.
  • Enterprise Plus: Includes all features of Standard and Enterprise Editions with additionally having Fault Tolerance upto 4 vCPUs and 64GB of RAM. It also includes Distributed vSwitch and the most expensive licensing option of vSphere 6.0.

87. How much Maximum RAM can vSphere 6.0 support?
Answer: It supports upto 12TB of RAM.

88. What is the Content Library?
Answer: Content Library is defined as the central location point between the two different geographical locations with vCenter Servers where we are capable of storing the ISO images, VM templates, scripts etc. and also sharing them between the different geographical locations.

89. What are the main benefits of content libraries?
Answer: We are capable of creating the VM templates and can be able to share on another geographical location of a company without the creation of other locations. It has many benefits such as the storage efficiency, sharing and consistency, and secure subscription.

90. How many types of Content Libraries exists?
Answer: It has three types:

  • Local: library of local control.
  • Published: It is the content library which is a local library having contenting (ISO images, VM templates etc) for the subscription.
  • Subscribed: A library which syncs with the published library.

91. What is VMFS?
Answer: VMFS is defined as a file system for a VM in the VMware vSphere. VMFS is also defined as a datastore which is responsible for the storage of the virtual machine files. The VM file system is also capable of storing the large files having sizes up to 64 Tera Byte in the vSphere 6.0.

92. What is vSAN?
Answer: Virtual SAN is a software-defined storage first introduced in vSphere 5.5 and is fully integrated with vSphere. Virtual SAN is used for aggregating the local attached storage of the ESXi hosts which is the part of a cluster and used for creating a distributed shared solution.

93. What is cold migration?
Answer: Moving a powered-off VM from the one host to the other is termed as cold migration.

94. What is Storage vMotion?
Answer: Moving a powered-on VM from one datastore to the other is termed as Storage vMotion.

95. What are the different configuration options for VSAN?
Answer: There are two configuration options for vSAN:

  • Hybrid: It is the configuration option which makes use of the both flash-based and magnetic disks for the storage purposes. Flash gets used for the caching while magnetic disks come into use for the capacity or storage.
  • All-Flash: It is the configuration option which makes use of the flash for both storage and for caching.

96. Are there VSAN ready nodes available in the market?
Answer: Yes, vSAN-ready such as VxRail 4.0 and 4.5 are available in the market. VxRail is defined asthe part of a cluster which is a combination of minimum 3 servers and it can scale up to 64 servers.

97. How many minimum servers/hosts are required to configure vSAN?
Answer: To configure a vSAN you should have a minimum of 3 ESXi hosts/servers in the form of a vSAN cluster. If one of the servers fails, a vSAN cluster will fail.

98. How many maximum ESXi hosts are allowed for vSAN?
Answer: 64 hosts are max allowed to configure a vSAN cluster.

99. How many disk groups and maximum magnetic disks are allowed in a single disk group?
Answer: Maximum 5 disk groups are allowed on an ESXi host which is a part of a vSAN cluster and a maximum of 7 magnetic and 1 SSD per disk group is allowed.

100. How many types of storages can we use in our virtual environment?

  • Direct Attached Storage
  • Fiber Channel (FC)
  • iSCSI
  • Network Attached Storage (NAS)

101. What is NFS?
Answer: Network File System (NFS) is a file sharing protocol that ESXi hosts uses to communicate with a NAS device. NAS is defined as a specialized storage device which is used for connecting to a network and can provide file access services to the ESXi hosts.

102. What is Raw Device Mapping (RDM)?
Answer: Raw Device Mapping (RDM) is defined as a file which is stored in a VMFS volume that acts as a proxy for a raw physical device. Raw Device Mapping enables you to store the virtual machine data directly on a LUN. Raw Device Mapping is recommended when a VM interact with a real disk on the SAN.

103. What is an iSCSI storage?
Answer: An iSCSI SAN consist of an iSCSI storage system which contains one or more storage processors. Transfer Control Protocol/Internet Protocol is used for the communication between host and storage array. An iSCSI initiator usually gets configured with the ESXi host. An iSCSI initiator can be defined as a hardware-based either independent or dependent and software-based which is known as the iSCSI software initiator.

104. What is the format of iSCSI addressing?
Answer: It makes use of the Transfer Control Protocol/ Internet Protocol for configuration.

105. What are iSCSI naming conventions?
Answer: ISCSI names are formatted in two ways:

  • the iSCSI qualified name (IQN)
  • extended unique identifier (EUI) vApp

106. What is vApp?
Answer: vApp is a container or group where more than one VM can be packaged and can manage multi-tiered applications for specific requirements. For example, Web server, database server, and application server can be configured as a vApp and can be defined as their power-on and power-off sequence.

107. What settings can be configured for vApp?
Answer: We can configure several settings for the vApp such as IP allocation policy, CPU and memory allocation etc.

108. What is VMware DRS?
Answer: DRS stands for Distributed Resource Scheduler that automatically balances available resources among various hosts by using cluster or resource pools. By taking the help of HA, DRS is capable of moving the VMs from one host to the other to balance the available resources among the VMs.

109. What are shares, limits and reservations?

  • Share: A value which is used for specifying the relative priority or the importance of a VM access for a given resource.
  • Limit: It is defined as consumption of a CPU cycle or the hosting of physical memory which cannot be crossing the defined value (limit).
  • Reservation: This value gets defined in the form of the memory or CPU and that must be available for a VM to start it.

110. What are the alarms and why do we use them?
Answer: An alarm is a notification which appears when an event occurs. Many default alarms exist for many inventory objects. Alarms can be modified and created by making use of vSphere Web Client.

111. What are the hot-pluggable devices which can be added while VM is running?
Answer: We are capable of adding the HDDs and NIC while the VM is running.

112. What is a Template?
Answer: When a VM is converted into a format which can be used to create a VM with predefined settings is termed as a template. We have an option that an installed VM can usually get converted into a template but it cannot be powered-on.

113. What is Snapshot?
Answer: To create a copy of a VM with the timestamp as a restore point is called a snapshot. Snapshots are taken when an upgrade or software installation is required. For better performance, a snapshot must be removed after the performance of a particular task.

114. How to convert a physical machine into a VM?
Answer: There are three steps which are required for converting a physical machine to a 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

115. What is vMotion and what is the main purpose to use it in a virtual environment?
Answer: It is a very prominent feature of VMware vSphere used to migrate run VMs from one ESXi host to another without any downtime. Data stores and ESXi hosts both can be used.

116. What is the difference between a clone and a template?
Answer: A clone is defined as a copy of the virtual machine in VMware. By cloning a VM, it will save the time if the multiple VMs that have the same configurations are required. While a template is a master copy of an image created from a VM which can be later used to create many clones. After converting a VM to a template, it can’t be powered-on or edited.

117. What type of the monitoring method do we use in vSphere HA?

  • Network Heartbeat
  • Datastore Heartbeat

118. How is the master host elected in vSphere HA?
Answer: When HA is enabled in a cluster, all the hosts which are taking part in a selection process to be selected as a master host. A host which has the highest number of data stores mounted will be selected as a master host. All other hosts will remain slave hosts.

119. What is the purpose of VMware Tools?
Answer: It is defined as a suite of utilities which are generally used to enhance the performance of a VM in the form of network card, graphics, mouse/keyboard movement and other peripheral devices.

120. What is VMware DPM?
Answer: A stand for Distributed Power Management is a feature of VMware DRS that is used to monitor required resources in a cluster. When the resources get decreased due to their low usage in the VMware then the VMware DPM used to consolidate the workloads and also used to shut down the hosts which are not being used at that time and when resources are increased then it automatically powers on the unused hosts.

121. What is the ESXi Shell?
Answer: It is defined as a command-line interface which is used for running repair and diagnostics of ESXi hosts. It is the shell which can be easily accessible via vCenter Server enable/disable, DCUI and also via SSH.

122. How to run ESXTOP on ESXi host?
Answer: For running ESXTOP on an ESXi host, we’ll require two prerequisites and they are as follows:

  • We should install vSphere Client on a host where we need to configure.
  • We should also enable SSH from DCUI by making use of the “Troubleshooting Options” link.

123. What is the difference when you use viclient connect to VC and directly to ESX server itself?
Answer: When you are connecting to the VC you are capable of managing the ESX server via vpxa (Agent on esx server). Then Vpxa is used to pass those requests to the hostd (management service on esx server). When you connect to the ESX server directly, you are also connected to the hostd (bypass vpxa). You are capable of extending this to a troubleshooting case where you are connected to esx for seeing one thing and connected to VC for seeing another. So the problem is more likely out of sync between the hostd and vpxa, “service vmware-vpxa restart” should take care of this.

124. What was the most difficult VMware related problem/issue you faced in a production environment and what were the specific steps you took to resolve it?

  • HA issues – because of the dns problems, the hosts are not able to communicate between each other or together. It is corrected by adding all servers ip’s in each server’s /etc/hosts file
  • The VM was not powered up – because the swap file was locked by another host, when I try to power on the VM it doesn’t on. After releasing the lock it’s powered on.

125. When was the last time you called VM Support and what was the issue?
Answer: There were some licensing related issues.

126. What was the most performance intensive production app that you supported in VMware and what were some of the challenges that it posed?
Answer: In exchange for a share point demo project, getting a lot of VLAN issues.

127. Can Host Profiles be used with a cluster running both ESX and ESXi hosts?
Answer: Yes, but we should remember that we should use an ESX host and not an ESXi host for creating a profile. In theory, Host Profiles should be working with the mixed host clusters as it used to translate ESX to ESXi but we should be careful as we must know that there are enough differences between ESX and ESXi that can be leading to make self-inflicted errors when applying for the Host Profiles. The easiest method for us is to create the clusters which are homogeneous in nature and maintaining two different profiles for these two types of clusters.

128. Can Host Profiles work when using the Cisco Nexus 1000v?
Answer: No, the Host Profiles does not work when we are using the Cisco Nexus 1000v because Host Profiles are generally used to design with the generic vNetwork Distributed Switch. The Cisco Nexus 1000v switch used to give administrators finer-grained control of the networking beyond what the Host Profiles can be applied.

129. What are host profiles?
Answer: These are defined as a set of best practice configuration rules that are applied to the whole cluster or to an individual host. So that all the hosts are in sync with each other. This will avoid the vmotion, DRS and HA problems.

130. What are the available Storage options for virtual machines?
Answer: Raw device mappings, VMFS

131. What are the differences between Virtual and Physical compatibility modes when mapping the Raw Devices to virtual machines?
Answer: You can configure RDM in two ways:
Virtual compatibility mode—this compatibility mode is used to fully virtualize the mapped device which used to appear to the guest operating system as a kind of virtual disk file on a VMFS volume. Virtual mode provides us with such benefits of VMFS as using snapshots and advanced file locking for data protection.
Physical compatibility mode—this compatibility mode used to provide us to access the most of the hardware characteristics of the mapped device. VMkernel is usually passing all the SCSI commands to the device with one exception, thereby exposing all the physical characteristics of the underlying hardware. In this compatibility mode the mapping is done by the following method when we create a mapping, the configuration is stored in a file and that file is stored along with the vm files in the datastore. This file points to the raw device and also makes it accessible to the vm.

132. What are Raw Data Mapping Limitations?
Answer: Raw Data Mapping limitations are as follows:
There are mainly two types of Raw Data Mappings: they are virtual compatibility mode Raw Data Mappings and physical compatibility mode Raw Data Mappings. Physical mode Raw Data Mappings, in particular have some fairly significant limitations which are as follows:

  • No VMware snapshots.
  • There is no VCB support in this because VCB needs the VMware snapshots.
  • There is no cloning VMs which is making use of the physical mode RDMs.
  • There is also no migration of the VMs with the physical mode RDMs if the migration involves copying the disk.
  • No VMotion with physical mode RDMs.

Virtual mode Raw Data Mappings address some of these issue, allowing raw LUNs to be treated very much like virtual disks and enabling functionality like VMotion, snap shooting, and cloning. Virtual mode Raw Data Mappings are mostly acceptable in most of the cases where there is a requirement of Raw Data Mappings. For example, we can make use of the virtual mode Raw Data Mappings in case of virtual-to-virtual clusters across the physical hosts. We should note that the physical-to-virtual clusters across the boxes, though, need the physical mode Raw Data Mappings.

While the virtual disks will be working for the large majority of applications and for the workloads in a VI environment, the using of the Raw Data Mappings–either the virtual mode Raw Data Mappings or physical mode Raw Data Mappings can help in eliminating potential compatibility issues or allowing the applications for running the virtualized without any loss of the functionality.

133. When users are logged in to their Virtual Machines via View Client when they wish to end the session should they choose the “disconnect” or “disconnect and log off” option?
Answer: The first option is Disconnect. With Disconnect, the user remains logged on. Any programs that the user is running then one must continue to run and no other users (except for an Administrator) can be connected to this desktop. If an administrator chooses to log in they may be logging into the desktop but will automatically log out the user and also force any programs that the user is running to end. The second option is disconnecting and Logging off. This option allows the user to log off and it allows other users to access this desktop.

134. What is the purpose of the cache lifetime setting for the offline desktop?
Answer: The data on the each offline system is having an encryption and a cache lifetime controlled through the policy. If the client is losing the contact with the View Connection Server, the cache lifetime is the period in which the user can continue to use the desktop before they are refused to access. This countdown is resettled once the connection is re-established.

135. Does Offline Desktop support are tunneled or non tunneled communications?
Answer: Offline Desktop support the tunneled or non tunneled communications for LAN based data transfers. When tunneling is enabled then all traffic gets routed through the View Connection Server.

136. What is the rationale behind utilizing virtual machines instead of original hardware?
Answer: Purchasing additional pieces of hardware such as computer systems shoots up the budget of a company. Buying a new unit also necessitates allocating funds separately for their maintenance. Virtualization is addressing all these needs after providing some of the reliable solutions to the companies for efficient working. Among other things, it reduces the requirement to invest in additional units by splitting up a physical server into multiple servers.

137. Is there any specific requirement for running ESXi in the BIOS of the server?
Answer: Yes, one needs to activate the NX/XD bit in order to ensure the smooth installation of the software programs that are necessary to run ESXi in the server.

138. Can the .nvram be recovered after accidental deletion from a virtual machine?
Answer: .Nvram helps a virtual machine to store its BIOS component. If it gets deleted for some reason it can be again recovered after powering on the virtual machine using a battery.

139. What are the four core elements of the VMkernel networking layer?
Answer: VMkernel networkings are the constructs that are tailor-made to facilitate vSphere to interact with the outside world. Its four core elements include the following:
Virtual SAN
Fault Tolerance
Science storage

140. What ports are needed if an administrator wants to connect vSphere net consumers with ESXi directly?
Answer: It may be necessary to use multiple ports for connecting vSphere net consumers with ESXi. These include 443 TCP, 902 TCP and UDP, and 903 TCP ports. An administrator can open these ports for operation from a security profile.

141. What valid identity supply is necessary for the configuration of vCenter SSO?
Answer: It is important to ensure the supply of a valid identity for the configuration of vCenter SSO without any issue. The valid identity supply necessary for the configuration of vCenter SSO is Open LDAP.

142. How does vCenter differ from vSphere?
Answer: vCenter is installed on a server that either runs on UNIX or Windows. This can either be a desktop or a laptop. On the other hand, vSphere is an application management system that can be managed in a centralized manner. It controls virtual machines centrally.

143. What is vLockstep Technology?
Answer: It is defined as a technology which is used for transferring the data from a primary virtual machine to a secondary virtual machine. The data includes events, movements, and inputs. This technology helps to capture these elements on a primary server and send them to the secondary server.

144. What is FT Logging?
Answer: FT Logging stands for Fault Tolerance Logging. At the time of configuring the Fault Tolerance, two ESXi hosts interact or communicate with each other.

145. Does FT work if the vCenter server goes down?
Answer: Yes, FT can work even as vCenter goes down. All a user needs to do is run fault tolerance (FT) on a virtual server. One of the downsides of vCenter going down is that it leads to a failover between primary and secondary machines.

146. What is Server Virtualization?
Answer: It allows the different operating systems to run on a single server that is highly efficient for the virtual machine. It provides ideal benefits to the industry.

  • It improves the efficiency of IT business operation
  • It minimizes the cost of operation
  • It is suitable for quick workload deployment
  • It is better to improve the performance of the application
  • It reduces server damage and complexity.

147. What is Network Virtualization?
Answer: It lets an application run on a virtual server if the application is running on the physical network. It gives greater operational benefit to the industry. This one is used for different purposes like:

  • Running protocol analyzer
  • Logical Ports
  • Switches
  • Load Balancer
  • VPNs
  • Firewalls and others

148. What is Application Virtualization?
Answer: Application runs on the host and installed in different forms. It is the application virtualization which could be accomplished by the streaming of application, desktop virtualization or VDI. It is also best-suited for increasing the mobility of various applications and permitting migration of VM from the host. It minimizes downtime of applications.

149. What is Presentation Virtualization?
Answer: It is the virtualization by which ICA protocol and Microsoft terminal services are developed. Any application can run on the host and allows the client to view on the screen and gain details of running the place.

150. What is Storage Virtualization?
Answer: The disk storage of data is combined and maintained by the virtual storage system. It also offers the abstraction layer which is ideal for the physical storage for maintaining and optimizing in virtual deployment.

151. What Are The Solutions Offered by VMware?
Answer: VMware is considered as the best standard for virtualization. It provides the widest range of solutions that are better for the business to improve the growth in a simple way. Here are some of the popular solutions that are offered by the Vmware:

(i) VMware Vcenter Site Recovery Manager:
This is very useful to keep the system running in case any failure occurs in hardware components. If the physical server gets damaged then all the data and the files are automatically shifted to the other server. It provides constant system availability and never minimizes uptime when waiting for any resource to fix the issues in the crashed server.

(ii) VMware Vcenter Server:
The solution helps you to minimize a number of the physical servers that a business needs to have. With the virtualization of the various servers this will be reducing the requirement of the services and decreasing the storage space in the server. It is better to lower the energy bill.

(iii) VMware Vcenter Lab Manager:
It lets anyone test different things like system configuration, software, and updates without compromising time and effort to change workstation.

(iv) VMware View:
It is a simple solution which maintains the desktop workstation and also creates a workstation virtual. Updates and software installations are handled at a single place. This will help you to save money. It is simply and easy to manage, support and provides complete control of the workstation.

152. What is the purpose of VM Tools?
Answer: VMware Tools are considered as a house of utilities that are aiming for enhancing the Virtual Machine’s performance of guest operating systems and for improving Virtual Machine’s management. Following issues are getting either removed or eliminated after the installment of the VMware Tools, which are as follows-

  • Low video resolution
  • Incorrect display of network speed
  • Inability to copy and paste and drag & drop files
  • Synchronization of time in the guest operating system with the time on the host and more.

153. What does VMware DRS mean?
Answer: VMware Distributed Resource Scheduler is defined as a tool which is used to dynamically balance the available resources across the various hosts by taking the help of Cluster or resource pool. VMware Distributed Resource Scheduler permits the users to formulate the rules and policies that fix the manner in which VMs will be sharing all the resources and how these resources are getting prioritized among the multiple VMs.

154. What does VMware DPM mean?
Answer: Distributed Power Management or DPM is defined as a tool which is used for monitoring required resources in a cluster. At times when resources get decreased due to low usage, VMware DPM merges workloads and shuts down the hosts that are unused and when the resources are increased, it automatically will on the unused hosts.

155. What does VMware HA mean?
Answer: VMware HA or High Availability is used for working on the host level and configuring on the Clusters. In case of any host level failure, a Cluster configured with HA will automatically migrate and restart all the VMs running under any of the hosts to another host below the identical Cluster. ALL ESX Server hosts in a cluster are monitored by VMware HA and they also detect failures.

156. Define promiscuous mode in VMware?
Answer: Promiscuous mode in VMware is defined as a security policy which is describable at the port group level or virtual switch. Use of promiscuous mode in a virtual machine, Service Console or VMKernel network interface in a port group helps it to see all network traffic traversing the virtual switch. If the promiscuous mode is set for rejection then the packets are to be sent to the intended port so that the targeted virtual machine will only be capable of seeing the communication.

157. Define VMware vMotion?
Answer: VMware VMotion helps in live migration of running virtual machines from one physical server to another with zero downtime. The entire pool of resources is automatically optimized and allocated by VMotion to get maximum hardware utilization and to perform hardware maintenance function without any scheduled downtime. It proactively migrates virtual machines away from failing or underperforming servers.

158. How does VMware HA differ from vMotion?
Answer: When any of the hosts inside a cluster fails then all the virtual machines running under it are restarted on different hosts under the same cluster with the help of VMware HA. For this migration of VMs to different hosts, VMware HA is completely dependent on vMotion. So the only use of vMotion is to assist in the migration process between multiple hosts. vMotion is defined as Laos which is capable enough for migrating any VM to any of the hosts which are inside the cluster without getting interrupted.

159. In a cluster of more than 3 hosts can a person tell Fault Tolerance where to put the Fault Tolerance virtual machine or does it choose on its own?
Answer: A person is capable of only placing the original or the Primary virtual machine. He has full control with DRS or vMotion for assigning it to any node. When the Secondary virtual machine gets created then it is placed automatically on the basis of the hosts that are available. But at the time of the creation and placement of the Secondary VM the person can move it to the preferring host.

160. What does VDI mean?
Answer: VDI is an acronym for Virtual Desktop Infrastructure where end user physical machines such as desktop or laptop are visualized because of which VDI is described as “delivering drops from the data center” by VMware. Once VDI is used with the help of a device called thin client, the end user can connect to their desktops.

161. Write the methods of converting a physical machine into a VM?
Answer: There are mainly 3 steps are essential for the conversion of a physical machine to a VM:

  • We should take care that there should be having an installed agent on the Physical machine.
  • We should remember that the VI client must be installed along with the Converter Plug-in.
  • A server should be there for exporting/importing the virtual machines.

162. What do you mean by Template?
Answer: At the time of converting a VM into a format which is basically used for building a VM with predefined settings is known as a template.

163. What do you mean by alarms?
Answer: An alarm is a kind of notification produced when any event happens. For inventory objects, default alarms exit.

164. Why do we use alarms?
Answer: We use alarms because it can be easily modified and created with the help of it. Alarms can be created with vSphere Web Client.

165. Define share?
Answer: Share is a value which postulates the relative priority or requirement of a VM access to the specified resource.

166. Define limit?
Answer: Consumption of a host physical memory or CPU cycle which is not able to cross the defined value is known as Limit.

167. What do you mean by reservation?
Answer: This value is described in the form of memory or CPU. Its presence is mandatory to be available to start a VM.

168. What are iSCSI naming conventions?
Answer: There are 2 ways of formatting iSCSI names which are mentioned below:

  • Extended unique identifier (EUI)
  • The iSCSI qualified name (IQN)

169. What are DRS? What are types of DRS?

  • Distributed Resource Scheduler
  • It is a feature of a cluster
  • DRS continuously monitors utilization across the hosts and moves virtual machines to balance the computing capacity
  • DRS uses vMotion for its functioning

Types of DRS

  • Fully automated – In this type of DRS the VMs are moved across the hosts in an automated manner. No admin intervention is required in this.
  • Partially automated – In this type of DRS the VMs are moved across the hosts in an automated manner during the time of VM booting up. But once up, vCenter will provide the DRS recommendations to the admin and has to perform it in a manual way.
  • Manual – In this, admin should have to act according to the recommendations of the DRS.
    DRS prerequisites
  • Shared storage.
  • Processor compatibility of the hosts in the cluster of the DRS.
  • vMotion prerequisites.

170. vMotion is not working. What are the possible reasons?

  • Ensure vMotion is enabled on all ESX/ESXi hosts.
  • One must also ensure that all VMware prerequisites should meet well.
  • Verify if the ESXi/ESX host can be reconnected or if reconnecting the ESX/ESXi host resolves the issue.
  • Verify that time is synchronized across the environment.
  • One must also verify that the required spacing of the disk is also available.

171. What happens if a host is taken to maintenance mode?
a. Hosts are taken to maintenance mode during the course of maintenance
b. In a single ESX/ESXi setup, all the VMs need to be shutdown before getting into maintenance mode
c. In a vCenter setup if DRS is enabled, the VMs will be migrated to other hosts automatically.

172. How will you clone a VM in an ESXi without vCenter?
a. Using vmkf tools
b. Copy the vmdk file and attach to a new VM
c. Using VMware converter

173. Recommended iSCSI configuration?
Answer: A separate vSwitch and a separate network other than VMtraffic network for iSCSI traffic. We must know that the dedicated physical NICs should be connected to the vSwitch configuration for the iSCSI traffic.

174. What is iSCSI port binding?
Answer: Port binding comes into use in iSCSI when the multiple VMkernel ports for iSCSI are residing in the same broadcast domain and IP subnet for allowing the multiple paths to an iSCSI array which broadcast a single IP address.

175. iSCSI port binding considerations?
a. Array Target iSCSI ports must reside in the same broadcast domain and IP subnet as the VMkernel port.
b. All VMkernel ports used for iSCSI connectivity must reside in the same broadcast domain and IP subnet.
c. All VMkernel ports used for iSCSI connectivity must reside in the same vSwitch.
d. Currently port binding does not support network routing.

176. Recommended iSCSI configuration of a 6 NIC infrastructure?
a. 2 NICs for VM traffic
b. 2 NICs for iSCSI traffic
c. 1 NIC for vMotion
d. 1 NIC for management network

177. What are the post conversion steps in P2V?
a. Adjust the virtual hardware settings as required
b. Remove non present device drivers
c. Remove all unnecessary devices such as serial ports, USB controllers, floppy drives etc.
d. Install VMware tools

178. Which esxtop metric will you use to confirm latency issues of storage?
Answer: esxtop –> d –> DAVG

179. What are standby NICs?
Answer: These are the adapters which will be used to become active if the so called defined active adapters have failed.

180. What are the path selection policies in ESXi?
a. Most Recently Used (MRU)
b. Fixed
c. Round Robin

181. Which networking features are recommended while using iSCSI traffic?
a. iSCSI port binding
b. Jumbo Frames

182. What are the Ports used by vCenter?
Answer: 80,443,902.

183. What is the ‘No Access’ role?
Answer: Users assigned with the ‘No Access’ role for an object are not capable of viewing or changing the object in any way.

184. When is a swap file created?
Answer: The swap file gets created when the guest Operating System is first installed in the VMware.

185. What is the active directory group, where the members of ESXi administrators will be by default?
Answer: ESX Admins

186. Which is the command used in ESXi to manage and retrieve information from virtual machines?
Answer: Vmware-command

187. Which is the command used in ESXi to view live performance data?
Answer: esxtop

188. Which command line tool is used in ESXi to manage virtual disk files?
Answer: vmkfstools

189. Which Port is used for vMotion?
Answer: 8000

190. What is the Log file location of the VMware host?
Answer: \var\log\vmware

191. Can you map a single physical NIC to multiple virtual switches?
Answer: No

192. Can you map a single virtual switch to multiple physical NICs?
Answer: Yes. This method is called NIC teaming.

193. VMKernel port group can be used for which purpose?
a. vMotion
b. Fault Tolerance Logging
c. Management traffic

194. Define the major difference between ESXi 5.1 and ESXi 5.5 free versions?
Answer: Till ESXi 5.1 free version we know that there has been a limit to the maximum physical memory and that is 32 GB. But from 5.5 onwards this limit has been lifted.

195. What is the maximum number of LUNs that can be attached to a host (ESXi 5.0)?
Answer: 256

196. What is the maximum number of vCPUs that can be assigned to a VM (ESXi 5.0)?
Answer: 32

197. How can you edit a VM template?
a. The VM templates cannot be modified as such
b. First , the VM template must be converted to a virtual machine
c. After making necessary machines in the virtual machine, convert the virtual machine back to template

198. How do you use the VMware tool?
Answer: Installing of the VMware tool to eliminate or enhance the issues like

  • Inadequate color depth.
  • Restricted mouse movement.
  • Low video resolution.
  • Incorrect Network display speed.
  • Inability to drag-n-drop files or copy-paste.
  • Syncing the time of the guest operating system and the host.
  • Support the guest-bound calls.
  • Ability to take the quested snapshots of the guest Operating System.

199. How do you justify that VMware is for easy access?
Answer: VMware comes with the several features making the user easy to access and maintain.

  • Easy to use wizard for settings configuration.
  • Web browser interface.
  • Tools to create and maintain hosts.
  • Easy maintenance of virtual machines.
  • Configure VMware settings with easy graphics.

200. What is the use of VMware Workstation?

  • It is used to facilitate the user to run more than one operating system on a single system simultaneously.
  • It is used to save the existing operating system configuration in the form of virtual machines.
  • Users may be working on various Operating Systems even without switching between the Operating Systems.

201. Explain The Physical Topology Of Virtual Infrastructure 3 Data Centre?
Answer: A typical VMware Infrastructure center of data consists of the basic physical building blocks such as x86 storage networks and arrays, computing servers, IP networks, a management server and the desktop clients.

202. What Are Resource Pools & what’s the Advantage of implementing them?
Answer: A VMware ESX Resource pool is defined as a pool of memory resources and CPU. Inside the resources, pools are getting allocated based on the memory and CPU used for sharing as defined. This pool can be associated with access control and the permissions and the clear management of resources to the virtual machines.

203. What options are available in the edit setting menu of virtual machines?
Answer: By right clicking the virtual machines, we can choose edit settings and modify one or more of the following metrics:
Hard disk
SCSI controller
Network adapter
CD/DVD Drive
USB controller
Video card
VMCI device
SATA controller
other device

204. I right click my virtual machine, choose the power option. I see that Shutdown Guest OS and restart Guest OS options are grayed out. The virtual machine is up and running. Power off, suspend reset options are available. What is the reason?
Answer: The options Shutdown Guest OS, restart Guest OS grayed out in Spite of virtual machines in power on , up and running status means that the vm tools that have been installed in this virtual machine are idle. To make use of these options, open console log into the virtual machine and perform tasks for few minutes to make sure the session is live. This will change the status of the idle vmware tools.

205. If the shutdown guest OS is grayed out what should I do?
Answer: We can power off the virtual machine or choose to restart the virtual machines. Shutdown guest OS is a graceful power off option but the above mentioned two options are equally good.

206. Restart Guest OS is in gray mode. I can’t change it. What should I do?
Answer: By pressing the restart button that performs the restart of the virtual machine as a whole.

207. What are the services that can be enabled in VMKernel port settings?
Answer: One or more of the following available services that can be enabled while configuring VMKernel port settings:
Fault Tolerance Logging
vSphere Replication
vSphere Replication NFC
Virtual SAN

208. When you are tasked to configure the Virtual adapter what are the different settings that need to be configured?
Answer: We must know that following settings that are needed to be configured as a part of VMKernel creation in the vsphere web client:
Port Properties – In this page TCP/IP stack is configured. In addition to these most important enabled services listing is available on this page. Depending on the project we need to choose one or more of following enabling services to make them available and they are fault tolerance logging, vsphere replication, vmotion, provisioning, management, vsphere replication nfc, virtual san NIC settings.
IPv4 settings – This can be a static IPv4 address wherein we specify network IP address, MAC address, choose default gateway. In case of DHCP this can be dynamic IP as well.
analyze impact page – It is the final validation page before we are finishing the creation of the virtual adapter.

209. What are the main options available in the navigator pane of a vSphere web client?
Answer: The four main vSphere ruling options are available by default as part of the navigator pane in the vSphere web client. This is available on the left side of the screen. The options are:
Hosts and clusters
VM’s and folders
These options can be pulled from the home menu tab as well.

210. Try launching the console when the virtual machine is powered off. What happens?
Answer: An error stating that the server is not available is displayed. The consoling could not be shown because the VM machine has been powered off (disconnected or suspended). Power on and connect the VM and re-launch the console for the reconnection. Click the vsphere web client logs for details. This can also take place when the consoling was open previously then the VM was powered off in-between.

211. What are the many different VM/Host rules types that can be chosen in DRS?
Answer: The VM/Host rules in the virtual machine DRS can be one of the following types which are as follows:
Keeping the virtual machines together – The virtual machines which get chosen are always maintained in the same host.
Separate virtual machines – The virtual machines which get chosen are distributed in the separate hosts.
Virtual machines to hosts – Chosen virtual machines are tied to hosts. This is very useful with the resource intensive virtual machines like ERP, SAP etc.
Virtual machines to virtual machines – In case of websites there are stack of vm’s that are dependent on each other and dependency need to be maintained.

212. What options are available in vcenter support server summary page?
Backup – Vcenter server database which can be default database as well as custom databases like oracle sql server can be backed up onto folder, FTP location etc.
By creating the supporting bundle – This will be creating the bundle in zipped format needed for the issue investigation by the vmware.
Reboot – vcenter reboot.
Shutdown – Shutdown vcenter.

213. What is the use of lockdown mode?
Answer: Lockdown mode prevents the remote users from directly logging into the hosts. The default option is disabled. There are two more options like normal, strict.

214. Where do you look for resource reservations in the ES cluster environment?
Answer: From the vcenter server, we can be monitoring the resource reservation of an ESX cluster. The information is available in the cluster monitoring tab. Following resource reservations can be monitored from here.

  1. CPU
  2. Memory
  3. Storage

215. What are the many different monitoring options available in web sphere clients while cluster configuration is in place?
Answer: Following details can be monitored in ESX cluster environment are:

  1. Issues
  2. Performance
  3. Profile Compliance
  4. Tasks & Events
  5. Resource Reservation
  6. vSphere HA
  7. Utilization

216. From where can you schedule a patch install in the ESX environment?
Answer: Each and every host in the vsphere web client is having an option for remediating the patching schedule. This task can be done immediately and can be scheduled as a task to be run in future. The Remediate button can be accessed from the update manager.

217. Can we install patches in the ESX environment while virtual machines are on?
Answer: Typically we try to remediate a patch install as a scheduled task. This will fail if virtual machines are on. If we are manually applying the patch again all the virtual machines in the host should be off for the patch installation to be a success.

218. What error message is displayed in the update manager when an attempt is made to install patches with virtual machines in one state?
Answer: A message which says Overall compliance status – Non-compliant is displayed in the update manager panel. We can click on the scan for updates button to make sure the overall compliance status is a success.

219. What is the main item that can be authored using vapp settings?
Answer: The starting sequence of the virtual machines can be configured in the starting order option of the vapp page. We can be specifying startup operation, startup sequence delaying which by default is 120ms. This value can be changed. Shutdown action can also be specified in this location.

220. What details can be accessed from within vSphere HA summary page?
Answer: When a vSphere HA (High availability) configuration is in its place, details of the same can be accessed from the vSphere High Availability summary page:
Standby Mode
Maintenance Mode
vSphere HA agent un configuration failures
Virtual machines – protected mode, unprotected mode.

221. What vSphere HA items can be monitored from the vSphere web client page?
Answer: Following parameters that can be monitored are as:
Summary – mode the hosts are in like standby mode, maintenance mode, virtual machines in protected mode, unprotected mode
Configuration issues
Data stores under APD or PDL – This option talks about all path down (or) permanent datastore loss, the main condition under which failover happens in a vmware host.

222. What is a slot in virtual environment terminology?
Answer: In day to day life while we are making use of the vmware, slot is used invariably. Slot refers to a virtual machine and not the host.

223. Does vsphere HA and DRS supplement to each other or complement to each other?
Answer: In the environment of vmware, DRS is defined as the distributed resource scheduling. As the name suggest High Availability is for making sure vmware systems are always up and running. DRS are related to performance in vmware environment.
vSphere HA – In case of host failure, failover is possible. Once the failed host comes back this is not made to master again.
DRS – Depending on the hosts which are the part of DRS, affinity and non-affinity are ruling the virtual machines which are distributed across the various hosts. The summary shows the state which in most cases is balanced.
Now DRS can supplement vsphere. vSphere High Availability is independent of the DRS. Ideally they complement each other. In most real-time cases both are in place. If the host fails vmotion of machines happens owing to vsphere. Once the host which has failed comes back then the resources are distributed with the DRS implementation.

224. In which scenario the vSphere HA will never work?
Answer: When there occurs a scenario wherein the storage of data is not accessible vSphere High Availability will not be working. There are more reasons from VMkernel networking etc.

225. I see some vmsn files in my datastore folder. What are those?
Answer: Snapshots which are created in the virtual machines are getting stored as snapshot files vmsn in the datastore. Snapshots creation and storing will be given a name which is reflected in these vmsn files.

226. Is vmware supported in MAC?
Answer: Yes, with the latest versions vmware is also supported in MAC. It is to be noted that there are some hardware specific issues related to MAC. To address these issues more information needs to be added to the vmx file.

227. What is the operating system requirement for running vcenter?
Answer: In case of the virtual machines windows 2008, windows 2012 Operating System are required for running the vcenter.
In the case of a physical box with windows 2008 or windows 2012 OS vcenter is supported.
Vcenter is supported on the top of vmware virtual appliances as well.

228. What is a virtual appliance?
Answer: Virtual appliance is a pre-configured virtual machine that can be used for many different purposes. One common usage is vcenter virtual appliance being the latest replication software from vmware.

229. Why do we make use of vcenter in a virtualized environment?
Answer: Vcenter is defined as the centralized management platform which is used for administering hosts, implementing features like high availability, DRS etc. Though there are many of the tasks that can be accomplished directly from within esx host client, a central inventory manages and maintains all hosts.

230. My database team feels that vm tools cause performance problems. Can I remove them?
Answer: Nope. Vm tools are 100% recommended to run in virtual machines. For the best practices all the virtual machines should be having the vm tools in place.

231. Is a syslog collector in vSphere the same as a syslog in ESXi host?
Answer: In ESXi host while we are launching the DCUI tool there is an option for accessing the system logs termed as syslog. This is a Linux implementation. Vmware photon OS is based on Linux only. This is different from syslog collectors in vsphere.

232. What is stored in the vcenter database?
Answer: vCenter database acts as a centralized repository for storing information about the hosts that are added to the vcenter inventory. In addition to this real-time performance metrics, statistics is stored in this database.

233. What are templates?
Answer: Templates are owned and stored within vcenter. Templates are protected entities within vcenter. Virtual machines need to be powered off to be created as the templates that are stored in the vcenter. These templates are deployed for replicating these virtual machines.

234. What happens to distributed virtual switches when vcenter is down?
Answer: Distributed virtual switches are owned by vcenter. Once the vcenter goes down then the vmware network remains unaffected. Changes to switches can’t be made until the vcenter server is backed up and running.

235. What is a vSphere client?
Answer: This is defined as a new browser based tool in the vmware 6.5 version. The traditional tool used for managing the hosts is vSphere web clients.

236. What is vmware CEIP?
Answer: CEIP is a vmware customer experience improvement program.

237. What is a server template?
Answer: In an environment typically it is defined as a startup setup without any product in the place, vmware templates are created after the installment of the operating system, installation of patches etc. This is a template with no applications installed. These templates can be easily deployed and customized using the sysprep tool. These are called server templates.

238. How do you choose the LUN while creating NFS datastore?
Answer: In the vmware environment, while we are trying to create NFS datastore by making use of vSphere web clients, there is no provision for choosing LUN or disks from the drop-down menu. In a NFS setup this is a configuration that is taken care of by the NFS file server. This is not the case while we create VMFS datastore.

239. What is a vswp file?
Answer: Swap files in the traditional systems are stored in the shared storage. Now, the swap files are getting stored in a local SSD. The vswp file is the swap file.

240. What is ballooning?
Answer: Vmware tools need virtual machines for swap out. This is termed as ballooning.

241. What is the number of cores?
Answer: Cores in virtual machines translate to the number of cpu’s in real-time.

242. You log into the datastore of a virtual machine. What are the entire files you see there? Can you explain the significance of each one of them?
Answer: Virtual machine configuration file – .vmx file. This file as the name suggests stores the configuration information of virtual machines. In case of MAC to fix the hardware issues this file needs to be modified and additional information needs to be included.
Virtual machine BIOS – .nvram
Virtual machine swap file – .vswp
Virtual machine suspended state file – .vmss

243. What is Promiscuous Mode on vSwitch? What happens if it sets to accept?
Answer: If the promiscuous mode is settled for accepting all the communication is visible to all the virtual machines. In other words all the packets are to be sent to all the ports on vSwitch. If the promiscuous mode settled for rejecting then the packets are sent to the intended port, so that the intended virtual machine would be capable to see the communication.

244. What are MAC address Changes? What happens if it is set to accept?
Answer: 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 is not matching with the MAC address in the Operating System this setting does not allow the incoming traffic to the VM. So by setting the reject Option both MAC addresses will remaine the same and the incoming traffic will be allowed for the VM.

245. What are Forged Transmits? What happens if it is set to accept?
Answer: 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 match 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 remain the same and the outgoing traffic will be allowed from the VM.

246. How to fix HA errors in VMware ESX Server?
1. Make sure that all the hosts in the cluster are capable of resolving each other by the host name.
2. If they are not able to do so, check the DNS settings.
3. Best solution is to add all the hosts names and ip addresses into /etc/hosts file on all ESX servers in the cluster. We should put the ESX server in maintenance mode before making any changes to it.
4. Exit from the maintenance mode and try to reconfigure the High Availability on all the ESX hosts one by one, that’s it and your problem will be fixed.

247. What is VMware Consolidated Backup?
Answer: VMware Consolidate Backup is defined as a Backup framework which has been developed by the VMware Company. It has been installed on the Windows Server box as a proxy. By making use of the third party backup tools like Veeam Backup software, Veritas Netback up we can take the backups of the virtual machines that are hosted on the ESX hosts. Simple VMware Consolidate Backups are used as mediators between the Virtual machines / ESX hosts and the backup software. It enables the backup operators for taking the backup at file level from the .vmdk files and also enables to taking the snapshots. And one more important feature is that it’s a LAN free backup solution considered as the Backup Proxy server which is directly connected to the SAN environment.

248. How is it used?
1. As you must know that the backup proxy (Windows server with the VM Consolidated Backup and the VM Backup Agent) server which is directly connected to the SAN.
2. The Backup agent (for ex: Veritas Netbackup / Veeam Backup) used to initiate the backup request through the VMware Consolidated Backup, it immediately used to take a snapshot of the VM from the storage of SAN and mounting the .vmdk file on the proxy server and taking the backup of the files inside the .vmdk
3. Those files are getting stored on a backup disk/tape drive.

249. Unable to power on the Virtual Machine, How to fix it?
Answer: If the virtual machine used to run in an esx hosts cluster, sometimes it won’t power on. Because the files which are associated with that VM are locked by the host at the time of running. So when you are trying to vmotion the vm from one host to another host, the first host releases those files and again gets locked by the second host.

250. So what is meant by locking here and why does it happen?
Answer: Locking is simply defined as the registration of a vm with a host. This happens every time when the vm is hosted on a host. This is helpful for preventing the access to the same vm for the remaining hosts in the cluster.

251. Why does the VM fail when trying to power it on?
Answer: When the files are associated with that VM, it is locked by a host and it won’t power on. At that time one must be unregistering the vm from the host by making use of the vmware-cmd utility.

252. Define VMware Storage Vmotion as Virtual Machine Relocation?
Answer: In this answer I would like to discuss and share my views about the new and outstanding technology that is “Storage VMotion”. Till now we have heard about what we understand by VMotion? How did that happen? With this knowledge we are going forward to learn about the new feature in vSphere. Storage VMotion is very similar to the VMotion in the means of migration of Virtual Machines from one location to the other without disturbance or without downtime in the services. When we are initiating the VMotion then the reference of the Virtual Machine is moving from one host to the other but not the data which is related to that of VM. With the Storage VMotion reference of the Virtual Machine remaining in the same location but the data is moving from the one location to another.

253. What is the task of Platform Services Controller (PSC)?
Answer: Platform Services Controller Interface is defined as a fully HTML5-based interface to administer and used to configure many of the services that are running on the Platform Services Controller.
By making use of the Platform Services Controller Interface you can be performing the tasks, such as:
Adding and Editing the Users and Groups for Single Sign-On
Adding Single Sign-On Identity Sources
Configuring Single Sign-On Policies (e.g. Password Policies)
Adding Certificate Stores
Adding and Revoking the Certificates.

254. What is the difference between hostd, Vpxa and vpxd.
VPXD-It simply means the Vcenter Server Service. If this service has been stopped then we will not be capable to connect to the Vcenter Server via Vsphere client.
VPXA-It is considered as the agent of Vcenter server. It is also termed as mini vcenter server which has been installed on the every esx server that is managed by the Vcenter server.
HOSTD- This is considered as the agent of ESX server, here VPXA uses to pass the information to the HOSTD and hostd uses to pass the information to the ESX server.

255. What is a content library and different types of libraries?
Answer: Content libraries are defined as the container objects for templates of VM, vApp templates and also for other types of files. vSphere administrators are capable of using the templates in the library for deploying the virtual machines and vApps in the vSphere inventory. Sharing of templates and files across the various multiple vCenter Server instances in same or different locations is used to bring out compliance, consistency, efficiency, and automation in the deployment of workloads at scale.
You are capable of creating and managing a content library from a single vCenter Server instance but you can also be sharing the library items to the other vCenter Server instances if HTTP(S) traffic is to be allowed between them.
You are capable of creating two types of libraries: local or subscribed library.

  • Local Libraries
    You can make use of a local library for storing the items in a single vCenter Server instance. You can also be publishing the local library so that the users from other vCenter Server systems have the capacity to subscribe to it. When you use to publish a content library externally, you can be configuring a password for the authentication.
    vApps templates and VM templates have been stored as the OVF file formats in the content library. You are also capable of uploading other file types, such as the text files, ISO images, and so on in a content library.
  • Subscribed Libraries
    You are also having an option of creating a subscribed library and populating its content by synchronizing to a local library. A subscribed library contains the copies of just the metadata of the library items or the local library files. The local library can have its location on the same vCenter Server instance as the subscribed library or the subscribed library can be referencing a local library on a different vCenter Server instance.

256. Explain Cross vCenter vMotion.

  • Prior to vSphere 6.0, we were not allowed to perform the live migration between the vSphere Distributed Switches. It had been limited within the vSwitch. After vSphere 6.0, vMotion is allowed across the vSwitches and even the vCenter Servers.
  • For enabling the migration across the vCenter Server instances your environment should be meeting to these requirements:
  • The source and destination vCenter Server instances and ESXi hosts must be running version 6.0 or later.
  • The long distance vMotion and cross vCenter Server features need an Enterprise plus license.
  • When we make use of the vSphere Web Client then the both vCenter Server instances should be in Enhanced Linked Mode and should be in the same vCenter Single Sign-On domain so that the source vCenter Server can be authenticated to the destination vCenter Server.
  • Both vCenter Server instances should be time-synchronized with each other for the correction of vCenter Single Sign-On token verification.
  • For the migration of the computing resources only both vCenter Server instances should have the connection to the shared virtual machine storage.

257. What is Cross-vSwitch vMotion?
Answer: With vSphere 6.0, It is possible to perform the migration across the Virtual switches (Distributed Switch or Standard switch), which transfers all the VDS port metadata during the migration. It is completely transparent to the Guest VM’s and there is no requirement of downtime for performing this operation across vSwitches. Only one requirement that should be met for the migration across vSwitches is that you should be having the L2 VM Connectivity.
Virtual Networking Migration

Source TypeDestination TypeSupported
Distributed SwitchDistributed SwitchYes
Distributed SwitchStandard SwitchNo
Standard SwitchStandard SwitchYes
Standard SwitchDistributed SwitchYes

258. What is Long-Distance vMotion?
Answer: Long distance vMotion can be referred to as the cross country vmotion. VMware vSphere 6.0 adds functionality for migrating the virtual machines over the long distances. You are now capable of performing the reliable migrations between the hosts and sites. For supporting the long distance vmotion you need an Enterprise plus license.

  • You should be having a RTT (round-trip time) latency of the 150 milliseconds or less, between the hosts.
  • Your license must be covering the vMotion across the long distances. The cross vCenter and long distance vMotion features must be requiring an Enterprise plus license.
  • vMotion Network ( L2 network).
  • Virtual Machine Network
  • vCenter Server 6.0 on Both Location
  • Both vCenter Server instances must be time-synchronized.
  • In vSphere Web Client, both vCenter Server instances must be in the same vCenter Single Sign-On domain and must be in the Enhanced Linked Mode.
  • vMotion network has at least 250 Mbps
    Possible to move VMs on below scenarios
  • From VSS to VSS
  • From VSS to VDS
  • From VDS to VDS

We must note that:
Source and the Destination VDS should be in the same version.
In VSS, network labels which are used for the virtual machine port groups are consistent in nature across the hosts.

259. What is Cross-vCenter Mixed-Version vMotion?
Answer: Cross-vCenter Mixed-Version vMotion used to support cloning or migrating a VM across the different versions of vSphere 6.x, for example a vSphere 6.5 and a vSphere 6.0 Update 3 environment. You can even perform these operations across completely different vCenter Single Sign-On Domains.

  • This includes all the VMware Cloud on AWS versions and vSphere 6.7.
  • VM that require the encrypted vMotion cannot make use of vMotion with a destination vCenter version prior to the vSphere 6.5 GA.
  • VMs that make use of the vSphere HA restart the priority properties introduced in vSphere 6.5 and cannot make use of vMotion and cold relocating with a destination vCenter version prior to the vSphere 6.5 GA
  • vSphere Encryption is not supported with cross vCenter Server cloning and motioning of the virtual machines.
  • Cross vCenter Server vMotion is not supported with 3rd party switches.

260. What is Per-VM Enhanced vMotion?
Answer: Enhanced vMotion Compatibility (EVC) is defined as a cluster feature that ensures CPU compatibility between hosts in a cluster, so that you can seamlessly migrate the virtual machines within the EVC cluster. Starting with vSphere 6.7, you can also enable, disable, or change the EVC mode at the virtual machine level. The per-VM EVC feature facilitates the migration of the virtual machine beyond the clusters and across the data centers and vCenter Server systems that are having different processors. Unlike the cluster-based EVC, you can be changing the per-VM EVC mode only when the virtual machine has been powered off.

261. What are the differences between clone and template in VMware?

Clone is defined as the copy of Virtual Machine.A Template is termed as the master copy of Virtual Machine.
Clones can be made when the VM has been powered on.It can be converted back to the VM to update the base machine.
We cannot convert back the cloned VM.A Template can convert back to the VM.
With the help of parent virtual machines, a linked clone can share virtual disks.It is possible to convert clones into a template, but not possible to convert Virtual Machines into a template when the machine is powered on.

262. Comparison between ESX and ESXi

vMA SupportAvailableAvailable

TroubleshootingIt is done by the Service ConsolingIt is done by the ESXi Shelling
Secure SyslogDisabledEnabled
Jumbo FramesSupportedSupported
Boot from SANSupportedSupported
Scripted InstallationSupportedSupported
Deployment using Auto DeployNot SupportedSupported
vSphere Web AccessIt is for the Experimental basisIt is for the Complete Management
Lockdown modeNot presentPresent
Latest VersionESX 4.1ESXi 6.7
Service ConsolePresentRemoved
Authentication of Active DirectorySupportedSupported
Network Management InterfaceService ConsoleESXi Shell
Hardware MonitoringThird-Party AgentsCIM providers
Software Patches and UpdatesSupported on Linux OSOnly a few Patches and Updates
Custom Image CreationNot SupportedSupported
Command-Line Administrationesxcfgesxcli
VMKernel NetworkStorage Connectivity, Fault Tolerance, vMotionManagement Network, Storage Connectivity, Fault Tolerance, vMotion, iSCSI

263. Write about the disk types in VMware vSphere?
Answer: There are mainly three disk types in the VMware vSphere which are as follows:
Eager Zeroes (Thick Provision): It is used in the VMware Fault Tolerance. The disk space requirement is allocated at the time of creation to VMs. When we compare it to other disk formats, this Eager Zeroed thick provision takes a lot of time in creating a virtual disk.
Lazy Zeroes (Thick Provision): In this disk format, every virtual disk can be created by default. There is an allocation of physical space for Virtual machines when the disk is created. We can convert this Lazy Zeroed thick provision into thick eager zeroed.
Thin Provision: Thin provision provides the disk space allocation to Virtual Machines. The disk size will increase in proportion to the data size.

264. Define VVoL, RDM, and NFS?
VVoL (Virtual Volume):
It is defined as a concept of new disk management of the Virtual Machine in vSphere 6.0 version which enables the operations of array-based at the virtual disk level. Virtual Volume can be created automatically when the virtual disk is created.
RDM (Raw Device Mapping):
Raw Device Mapping is a file which is stored in the VMFS volume acts as a proxy for the devices which are in natural physical form. RDM is used for storing the data of the virtual machines on LUN.
NFS (Network File System):
NFS is defined as a file-sharing protocol that is used for communication with NAS (Network Attached Storage) devices. It connects to a network and gives file access services to the hosts of the ESXI.

265. Define configuration options in VSAN?
Answer: There are two configuration options in VSAN:

  • Hybrid
  • All-Flash

Hybrid: Uses both magnetic and flash-based disks for storage. The magnetic disks are used for storage or capacity, while flash-based drives are used for cash.

All-Flash: It uses flash for both storage and caching.

266. What are the steps in converting a physical machine into a virtual machine?
Answer: The following are the three steps required to convert a physical machine into a virtual machine:

  • One should remember that at initial, an agent should be installed on the physical machine.
  • One must also take care that along with the Converter plug-in there is also the installment of a VI client.
  • Needs a server to Export/Import the virtual machine.

267. Define VMware DPM and ESXi Shell.
Answer: VMware DPM:
VMware DPM (Distributed Power Management) is defined as a feature of VMware DRS which is used for monitoring the cluster resources. VMware DPM is used to shut down the unused hosts and also consolidate the workloads when the resources are getting decreased. If the resources get increased, then it automatically powers-on the hosts that are not being used.
ESXi Shell:
ESXi Shell is defined as a command-line which is used for repairing the ESXi hosts. It can be accessed through vCenter Server disable/enable, DCUI, and SSH.

268. What are the prerequisites needed in running ESXTOP on an ESXi host?
Answer: We require two pre-requisites for the running of ESXTOP on ESXi:

  • Initially, install a vSphere client in which you want to configure the host.
  • By making use of the Troubleshooting options and enabling SSH.

269. Define Limit, Share, and Reservation in VMware?

  • Limit: It is defined as the Host cycle consumption without crossing the defined value.
  • Share: It specifies the importance or relative priority of virtual machine access in a given resource.
  • Reservation: It is a value that is defined in the form of memory or CPU that can be available for the virtual machine to start.

270. What is vApp, and how is it useful?
Answer: vApp is defined as a group or container in which more than one virtual machine can be managed in multi tired apps for specific requirements like a database server, Web server, and application server. It also defines the power-off and power-on sequences of the virtual machine. By using vApp we can configure several settings like memory allocation and Internet Protocol allocation policy.

271. What is meant by iSCSI storage, and what are its naming conventions?
Answer: An iSCSI storage system holds in iSCSI SAN that contains more than one storage processor. The communication between storage arrays and hosts can be made possible through the TCP/IP protocol. The configuration of iSCSI initiator is done with ESXi host. The iSCSI initiator is the initiator which is not either dependent or independent; that’s why it is termed as the iSCSI software initiator.
The names iSCSI can be formatted in two ways:

  • Extended Unique Identifier (EUI)
  • ISCSI Qualified Name (IQN)

272. What are the types of Content Libraries?
Answer: There are three types of Content Libraries:
Published: It is the local library that consist of VM templates, ISO images for the subscription.
Local: Local control library.
Subscribed: It syncs with the library published.

273. What are the limitations and requirements of a Content Library?
Answer: The following are the limitations and requirements of a Content library:
●Every library consists of a maximum of 256 items.
●The size of single storage is up to 64TB.
●For every 24 hours, the sync is happening.

274. What are the types of extensions in VMware?
.nvram: It is used for stocking the virtual machine state BIOS of an organization.
.vmsd: It provisions the metadata and information of the snapshots in an organization.
.vmss: It supplies the virtual machine postponed state.
.vmx: It accumulates the primary formations in the virtual machine.
.log: It is used for saving log files for VMware for seeing the glitches during the process of installation.
.vmdk: It is used to simulate the disk file to stock the virtual machine gratify.
.vmsn: It is used for the storing of the snap state. It can supply both consecutive states and the occupied period.

275. Define the components that are used in vCenter Server architecture?
Answer: There are three main components in the architecture of the vCenter Server:
Web Client and vSphere Client: It is a user interface.
vCenter Server Database: Embedded PostgreSQL or SQL server is used to store security roles, inventory, and resource pools.
SSO: It is a security domain.

276. What is meant by VCB, and what are its benefits?
Answer: VMware Consolidated Backup (VCB) is referred to as the backup framework which is enabling the third-party tools to get backups. VCB is very much helpful to back up the virtual servers of VMware ESX. VCB is also known as ‘’Backup Proxy Server” and is not considered as backup software. While using this VCB also, one must need backup software.

The Benefits of VCB:

  • It also provides the VMware ESX backups that are both incremental and full of file-level availability.
  • It prevents a backup loading agent on the virtual machines.
  • VCB is used for the centralization of VMware ESX backups.
  • It also provides the backups of image level.
  • It prevents the shut down of virtual machines.
  • VCB provides LAN-free backups because the connection of the VCB server to the SAN is made through the adapter of the fiber channel.
  • It also provides the virtual server centralized storage backups on the VCB server.
  • It also helps in reducing the VMware ESX server load without having a third party backup agent.
  • VCB utilizes the snapshots of VMware.

277. What are the types of deployments in vCenter Server?
Answer: There are two types of deployments in vCenter Server

  • External Deployment
  • Embedded Deployment

278. What is VMware vMotion and what are its requirements?
Answer: VMware VMotion enable the live migration of the running virtual machines from one physical server to the other with downtime zero.
VMotion lets you:

  •  It automatically optimizes and allocates the entire pools of the resources for maximum hardware utilization.
  •  It is used for performing the hardware maintenance without any scheduled downtime.
  •  It is used proactively for migrating virtual machines away from underperforming servers or
    Below are the prerequisites for configuring vMotion
  • One must take care that each host should be fairly licensed for the 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 sharing 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 make use of vMotion for migrating the virtual machines with raw device mapping (RDM) files by making sure to maintain consistent LUN IDs for raw device mapping across all the participating hosts.
  • Each host must meet the networking requirements
  • Configure a VMkernel port on each host.
  • It is dedicated to at least one GigE adapter for the vMotion.
  • Use at least one 10 GigE adapters if you migrate workloads that have many memory operations.
  • Use jumbo frames for best vMotion performance.
  • It is also ensuring that the jumbo frames are enabled on all network devices that are on the path of vMotion including the physical NICs, virtual switches and physical switches.

279. Clone Vs Template in VMware?
          Clone – A Copy of a virtual machine

  • Can’t restore the cloned Virtual Machine.
  • The cloning of a Virtual Machine also is created while the Virtual Machine has been switched on.
  • Cloning can be done in two ways namely Full Clone and Linked Clone.
  • A full type of cloning is considered as an independent copy of a virtual machine that is sharing nothing with the parent virtual machine after  the cloning operation. Ongoing operation of a full cloning is completely separated from the parent virtual machine.
  • A linked cloning is defined as a copying of a virtual machine which is sharing the virtual disks with the parent virtual machine in an ongoing manner. This is conserving the disk space and allowing the multiple virtual machines for using the same software installation.
  • Cloning a virtual machine can save time if you are deploying too many similar virtual machines. You are having an option of creating, configuring, and installing software on a single virtual machine, and then cloning it multiple times, rather than for creating and configuring each virtual machine individually.
    Template – It is defined as a baseline image or master copy of a virtual machine that can be used for creating many clones.
  • Templates cannot be powered on or edited and are more difficult for altering than an ordinary virtual machine.
  • You can convert the template back to Virtual Machine in order to update the base template with the latest released patches and updates and to install or upgrade any software and again convert back to the template which is to be used for the future deployment of the Virtual Machines with the latest patches.
  • It is helpful in converting the virtual Machine to a template that can’t be performed, when Virtual machine is powered on. Only Clone to the Template can be performed when the Virtual Machine is powering on.
  • A template offers a more secure way of preserving a virtual machine configuration that you wanted to deploy many times.
  • While you are cloning a virtual machine or deploying a virtual machine by a template the resulting cloned virtual machine will be independent of the original template or virtual machine.

280. What is the difference between Thick provision Lazy Zeroed, Thick provision Eager Zeroed and Thin provision?
Thick Provision Lazy Zeroes

  • It is advantageous in creating a virtual disk in a default thick format.
  • The spacing which is required for the virtual disk is allocated when the virtual disk is created.
  • The data that is remaining on the physical device is not usually erased during the creation but is zeroed out on-demand at a later time on the first writing from the virtual machine.
  • By making use of the default flat virtual disk format which does not zero out or eliminate the possibility of the recovering deleted files or restoring old data that may be present in this allocated space.
  • You are not capable of converting a flat disk to a thin disk.

Thick Provision Eager Zeroes

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

Thin Provision

  • It provides on-demand allocation of blocks of data.
  • All the space allocated at the time of the creation of a 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 the help of the thin provisioning the storage capacity utilization efficiency can be automatically driven up towards the 100% with very little administrative overhead.

281. What is the difference between Type 1 and Type 2 Hypervisor?
Type 1 Hypervisor

  • This is also termed as the Native Hypervisor or Bare Metal or Embedded Hypervisor.
  • It works directly on the hardware of the host and can monitor the operating systems that are running above the hypervisor.
  • It is completely independent of the Operating System.
  • The hypervisor is small as its basic task is to share and manage the hardware resources between the different operating systems.
  • The main advantage is that any problems that are having one guest operating system or virtual machine do not affect the other guest operating systems which are running on the hypervisor.
  • Examples are – Microsoft Hyper-V, VMware ESXi Server, Citrix/Xen Server

Type 2 Hypervisor

  • This is also termed as the Hosted Hypervisor.
  • In this case, the hypervisor is installed on an operating system and then it is supports other operating systems above it.
  • It is completely dependent on the host Operating System for its operations.
  • While it is having a base operating system it allows the better specification of the policies, any problems in the base operating system is affecting the entire system as well as the hypervisor which is running above the base Operating System is secured.
  • Examples are – VMware Workstation, Microsoft Virtual PC, and Oracle Virtual Box.


The above listed 281 Frequently asked  VMWare interview questions were compiled with an objective to help freshers and experienced VMWare professionals in their job interviews. Please go through these TOP VMWare interview questions to get better prepared for your next interview.

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