Most Asked VMware Interview Questions

1) What is VMware?

VMware is a virtualization and cloud computing software provider which provides different applications and software for virtualization. When we install VMware server visualization, it creates a hypervisor on the physical layer, allowing multiple virtual machines to run on the same physical server.

We can categorize VMware products into two levels, desktop applications and Server applications.

2) What is hypervisor in VMware?

A hypervisor is a program used to enable multiple operating systems to share a single hardware host. Each operating system consists of a host's processor, memory, and other resources. The hypervisor has to control the resources and host processor, allocating what is required for each operating system in turn and making sure that the guest operating system cannot disrupt each other.

3) What is the benefit of using VMware?

A list of benefits of using VMware:

• VMware is mainly used for running multiple operating systems and applications on a single computer system.
• You can get two computer systems' benefits by installing two different operating systems on a single computer. In this way, you can save more than 50% of the total cost spend on IT.
• By using VMware, you can simplify IT management and speed up the deployment of new applications.
• It consolidates hardware to get vastly higher productivity from fewer servers.

4) What are the different types of virtualization available?

Following are the four different types of virtualization available:

• Application virtualization
• Presentation virtualization
• Network virtualization
• Storage virtualization

5) What do you understand by VMware cloud?

VMware Cloud on AWS is an integrated cloud provider developed by AWS and VMware. It ensures the delivery of an extremely ascendable, secure, and innovative service that allows organizations to seamlessly migrate and extend their on-premises VMwarevSphere-based environments to the AWS Cloud running on next-generation Amazon Elastic.

It provides consistent infrastructure and operations for new and existing cloud-native applications, from the data center to cloud to edge. This consistency improves agility and reduces complexity, cost and risk.

6) What is VMware Server?

VMware Server is virtualization software used to create an atmosphere where we can make partition of one physical server into multiple virtual machines. We can use the VMware server easily with Windows, Solaris, UNIX, and Netware. We can use any of them or all at the same time on equivalent hardware.

7) What do you understand by VMware vCenter server?

VMware vCenter is a centralized management application that facilitates us to manage virtual machines and ESXi hosts centrally.

8) Which types of server software VMware provides?

VMware provides the following three different types of server software:

• VMware ESX Server
• VMware ESXi Server
• VMware Server

9) What is the use of VMware ESXi?

VMware ESXi is an associate enterprise-class, type-1 hypervisor developed by VMware. It is used for deploying and serving virtual computers. ESXi is also used to replace Service Console with a lot of closely integrated OS. ESX/ESXi is that the primary element within the VMware Infrastructure package suite.

10) What is VMware DRS?

The full form of VMware DRS is "Distributed Resource Scheduler." It is used to dynamically balance the resources across various hosts under a cluster or resource pool. Using this, a user can determine the rules and policies that decide how virtual machines deploy resources to multiple virtual machines.

11) What do you understand by VMware Fault Tolerance?

VMware fault tolerance is an essential component of VMware vSphere. It is used to provide continuous access to applications by preventing data loss and downtime of virtual machines in ESX server failure.

12) What are the different components used in VMware infrastructure?

Following is the list of different components used in VMware infrastructure:

• ESX server host
• Virtual Centre Server
• Virtual Infrastructure (VI) client
• Web Browser
• License Server
• Database

13) What are the storage and availability options in vCloud Suite?

The storage and availability options in vCloud Computing Suite are:

Storage DRS: It is used to place and load balance virtual machines based on storage capacity and I/O latency.

Storage vMotion: It is a proactive, non-disruptive storage migration used to reduce virtual machine storage, I/O bottlenecks and free up valuable storage capacity.

Data Protection: It is used to deploy a back-up and recovery tool based on EMC.

14) What do you understand by Host Isolation in VMware HA?

VMware HA stands for VMware High Availability. It has a mechanism used to detect a host isolated from the rest of the cluster hosts. In simple words, we can say that VMware HA uses a heartbeat to communicate with another host in the cluster. When the ESX host fails to connect with other hosts in a cluster through heartbeat, the VMware ESX host is called a Host Isolation.

15) What is the difference between VMware HA and VMware FT?

VMware FT ensures availability by keeping VMware copies on a separate host machine that makes it fault-tolerant even in the case of failure.

Following are some critical differences between VMware HA and VMware FT:

• VMware FT stands for Fault Tolerance. VMware HA stands for High Availability.
• VMware FT is enabled per VM basis, while the VMware HA is enabled per cluster.
• In the case of VMware HA configuration, the hypervisor attempts to restart the VM on the same host cluster so, if the physical infrastructure is powering that host face any problem, HA may not work. On the other hand, with VMware FT configuration, the VM workload is moved to a separate host. So, it does not face any downtime.
• In VMware FT, if one host fails, it will activate the secondary VM, and it becomes primary and continues to run from the same point where the primary VM is failed or left off.

16) What are the new and latest features available in vSphere 5?

The latest version of vSphere 5.5 consists of the following features:

• ESXi Hypervisor enhancement
• Virtual Machine Enhancement
• VMware vCenter Server Enhancement
• vSphere storage Enhancement
• vSphere Networking Enhancements

17) What do you understand by VMware vSphere?

VMware suite is globally known as VMware vSphere. It includes virtualization, management, and interface layers. The most critical and essential components of VMware vSphere are the ESXi server and the vCenter Server.

18) What is the full form of NFS in VMware?

In VMware, NFS stands for Network File System. It is a file-sharing protocol that uses a communication bridge between ESXi hosts and NAS (Network-attached storage) devices over a TCP/IP network. It is used to store ISO images, templates, virtual machine files, etc.

19) What do you understand by RDM in VMware?

RDM stands for Raw Device Mapping. It is a mapping file located in VMFS volume and acts as a proxy for the raw physical storage devices. It facilitates virtual machines to read and write from the storage. It also contains metadata to manage and redirect the disk to the physical device. It also allows us to use Vmotion, file system and adding raw LUNs to the virtual machine.

20) What is the full form of vSS in VMware?

In VMware, vSS stands for Virtual Standard. It is mainly responsible for communication between virtual machines hosted on a single physical host. It automatically detects a virtual machine that wants to communicate with other virtual machines on the same physical server.

21) What are some key features of the VMware tool?

Following are some key features of the VMware tool:

• It provides a simple wizard for setting configuration.
• It supports a web browser interface.
• It makes the maintenance of virtual machines easy.

22) What is the benefit of using VMware Workstation?

Following are three main reasons for using VMware workstation:

• VMware workstation facilitates the users to run more than one operating system on a single system.
• It makes you able to work on different operating systems without switching between them.
• It allows you to save the existing operating system configuration in the form of virtual machines.

23) What will happen if you accidently delete the .nvram file from a VM?

The .nvram file is employed to store the BIOS state of a virtual machine. If you accidently delete this file, it will be created once more when you power on the virtual machine.

24) What do you understand by Cold and Hot Migration?

Cold migration occurs when you migrate powered off or suspended. On the other hand, when you migrate your running power on virtual machines, it is called hot migration.

25) Explain the different types of virtualization in VMware in detail.

Following are the essential types of virtualization available in VMware:

Server Virtualization: It is used to consolidate multiple physical servers into virtual servers that run on a single physical server.

Application Virtualization: It is used to make an application run on another host from where you can install it in various ways. The application virtualization could be done by application streaming, desktop virtualization or VDI, or a VM package (like VMware ACE creates with a player). An example of Application virtualization is Microsoft Softgrid.

Network Virtualization: Network virtualization is used for multiple purposes, such as running a protocol analyzer inside an Ethernet switch. Components of a virtual network are NICs, switches, VLANs, network storage devices, virtual network containers, network media, etc.

Presentation Virtualization: The presentation virtualization is used to run an application on another host, and you can see it on the client the screen from where it is run. This is the same as Citrix Met frame and Microsoft Terminal Services can create.

Storage Virtualization: Storage virtualization is used to ensure that the virtual storage system can consolidate and manage the disk/data storage for your data. The servers connected to the storage system don't know from where the data comes. Sometimes, the storage virtualization is also described as "abstracting the logical storage from the physical storage.

26) What are the different versions of VMware ESXi, and which hardware is used with these versions?

The following table specifies the different versions of VMware ESXi and also the different hardware used along with them:

27) What is a .vmdk file in VMware?

The .vmdk file in VMware is the disk descriptor file that describes the virtual disk file's size and geometry. This file exists in the virtual hard drive that is assigned to the virtual machine.

28) What do you understand by VMware VMotion, and what is its requirement?

VMware VMotion is used to migrate the running virtual machines from one physical server to another with zero downtime. VMotion facilitates us to do the following things:

• It can automatically optimize and allocate entire pools of resources for maximum hardware utilization and perform hardware maintenance without any scheduled downtime.
• It can proactively migrate virtual machines away from failing or underperforming servers.

29) What are the prerequisites for configuring vMotion in VMware?

Following are the prerequisites for configuring vMotion:

• You must have the correct license for vMotion for each host.
• Each host must fulfill the requirements for shared storage.
• Each host must fulfill the networking requirements.
• vMotion migrates the VM from one host to another, which is only possible with both the host sharing common storage or any storage accessible by both the source and target hosts.
• A shared storage can be on a Fibre Channel storage area network (SAN) or implemented using iSCSI SAN and NAS.
• You have to configure a VMkernel port on each host.
• You have to dedicate at least one GigE adapter for vMotion.
• You have to use at least one 10 GigE adapters if you migrate workloads with many memory operations.
• You have to use jumbo frames for best vMotion performance and make sure that jumbo frames are enabled on all network devices on the vMotion path, including physical NICs, physical switches, and virtual switches.

30) What is the importance of snapshots in VMWare?

A VMWare snapshot is a copy of a virtual machine disk file used to restore a virtual machine to a specific point when the system fails or gets any error.

31) What is the use of port groups in data center virtualization?

Port groups are used to separate the network traffic. For example FT, management traffic, vMotion, etc.

32) What is the use of Promiscuous Mode in VMware?

Promiscuous mode is used to run a virtual machine with network sniffers to capture the packet of that network. By setting the promiscuous mode to accept, you can see all the communication visible to all the virtual machines.

33) What do you understand by VVol in VMware?

The full form of VVol is Virtual Volume. It is a new VM disk management feature introduced in vSphere 6.0. It is used to enable array-based operation at the virtual disk level.

VVol is automatically created when a virtual disk is made in a virtual environment.

34) What is VMKernel in VMware? What is the importance of it?

VMKernel is a virtualization interface between a VM and the ESXi host, which stores VMs. It is mainly used to allocate all available resources from host to VMs such as memory, CPU, storage, etc. VMKernal is also responsible for controlling special services like vMotion, Fault tolerance, NFS, traffic management, and iSCSI.

35) What do you understand by VMKernal adapter, and what is its use?

VMKernal adapter provides network connectivity to the ESXi host to handle network traffic such as vMotion, IP Storage, NAS, Fault Tolerance, and vSAN.

36) What are the drawbacks of the VMware virtualization platform?

Following are the main drawbacks of the VMware virtualization platform:

• You have a considerable investment to buy the resources of the VMware virtualization platform.
• It needs a high-end server, which will increase the cost.
• You must know different technologies to implement a VMware virtualization platform.

37) Which technology is used in VMware FT?

The vLockstep technology is used in VMware FT.

38) What do you understand by Vlockstep technology?

The Vlockstep technology is used to capture inputs, movements, and events on a primary VM and send them to a secondary VM. Each traffic type such as vMotion, vSAN, etc., requires a separate VMKernal adapter for creation and configuration.

39) What is VLAN, and why is it used in virtual networking in Datacenter?

VLAN stands for Virtual Local Area Network. It is a logical configuration of workstations, servers, and network devices that appear to be on the same LAN despite their geographical distribution.

40) What are the different Disk Types in VMware?

Following are the main three types of disk types in VMware:

• Thin Disks: Thin disks are dynamic, and due to their dynamic nature, these are the most used disks in the virtual machine. Thin disks allocate the space on the disk on demand.
• Thick provision lazy zeroed: Thick provision lazy zeroed is used when we have to allocate all the space from the datastore to the VM at the time of creation only. When the disk is created first, it is not erased but zeroed out on demand while writing the virtual machine's data.
• Thick provision eager zeroed: Thick provision eager zeroed is used when we have to allocate the whole disk space at the time of creation from the datastore. When this disk is created, all the data is zeroed out of the disk. This disk usually takes a much longer time as compared to other disks.

41) What is Content Library in VMware?

Content Library is the central location shared between geographical locations with vCenter Servers where you can store VM templates, ISO images, scripts, etc.

42) What is the difference between Clone and Template?

Let's see the differences between Template and Clone in the following table:

43) What is RDM, and why is it used?

RDM stands for Raw Device Mapping. It is a file stored in a VMFS volume that acts as a proxy for a raw physical device. It facilitates users to store virtual machine data directly on a LUN. It is recommended when a VM must interact with a real disk on the SAN.