Interview Questions.

Question 1. What Is A Hypervisor?

Answer :

It is a program that lets in multiple working systems to proportion a unmarried hardware host. Each working gadget seems to have the host's processor, memory, and other assets all to itself. However, the hypervisor is surely controlling the host processor and sources, allocating what is needed to each running system in turn and making sure that the visitor working structures (referred to as virtual machines) can not disrupt every different.

Question 2. What Is The Hardware Version Used In Vmware Esxi 5.5?

Answer :

Version 10, And products in vesion 10 are ESXi 5.5, Fusion 6.X, Workstation 10.X, Player 6.X.

Hyper-V Interview Questions
Question three. What Is The Difference Between The Vsphere Esx And Esxi Architectures?

Answer :

VMware ESX and ESXi are each naked steel hypervisor architectures that installation directly at the server hardware.

Although neither hypervisor architectures relies on an OS for aid management, the vSphere ESX architecture trusted a Linux operating gadget, referred to as the Console OS (COS) or provider console, to perform two management functions: executing scripts and putting in 1/3-celebration sellers for hardware tracking, backup or structures management.

In the vSphere ESXi architecture, the carrier console has been eliminated. The smaller code base of vSphere ESXi represents a smaller “assault surface” and less code to patch, improving reliability and protection

Question 4. What Is A .Vmdk File?

Answer :

This isn't the record containing the raw records. Instead it's far the disk descriptor file which describes the size and geometry of the virtual disk document. This file is in textual content format and incorporates the call of the –flat.Vmdk report for which it's miles associated with and also the difficult pressure adapter type, force sectors, heads and cylinders, and so forth. One of those documents will exist for each digital tough force that is assigned for your digital device. You can tell which –flat.Vmdk document it's far associated with by establishing the document and looking on the Extent Description subject.

Question 5. What Are The Different Types Of Virtualization?

Answer :

Server Virtualization: consolidating multiple bodily servers into digital servers that run on a unmarried bodily server.

Application Virtualization: an software runs on any other host from in which it's far established in a variety of ways. It may be carried out by means of utility streaming, computing device virtualization or VDI, or a VM package deal (like VMware ACE creates with a player). Microsoft Softgrid is an example of Application virtualization.

Presentation Virtualization: This is what Citrix Met frame (and the ICA protocol) in addition to Microsoft Terminal Services (and RDP) are able to create. With presentation virtualization, an utility surely runs on some other host and all that you see at the patron is the display screen from in which it is run.

Network Virtualization: with network virtualization, the community is “carved up” and may be used for multiple purposes together with running a protocol analyzer inside an Ethernet transfer. Components of a virtual network may want to include NICs, switches, VLANs, community garage gadgets, virtual network packing containers, and community media.

Storage Virtualization: with garage virtualization, the disk/information garage on your facts is consolidated to and managed by means of a digital storage gadget. The servers connected to the storage system aren’t aware of where the records virtually is. Storage virtualization is occasionally described as “abstracting the logical storage from the physical storage.

Red Hat Linux System Administration Interview Questions
Question 6. What Is Vmware Vmotion And What Are Its Requirements?

Answer :

VMware VMotion allows the stay migration of walking virtual machines from one bodily server to another with 0 downtime.

VMotion helps you to:

Automatically optimize and allocate whole pools of assets for optimum hardware utilization and
availability.
Perform hardware preservation with none scheduled downtime.
Proactively migrate digital machines far from failing or beneath performing servers.
Below are the pre-requisites for configuring vMotion

Each host should be efficaciously certified for vMotion
Each host ought to meet shared storage requirements
vMotion migrates the vm from one host to every other that is only viable with both the host are sharing a commonplace storage or to any storage reachable by means of each the supply and goal hosts. 
A shared storage can be on a Fibre Channel garage region network (SAN), or can be implemented the usage of iSCSI SAN and NAS.
If you use vMotion emigrate digital machines with uncooked tool mapping (RDM) files, make sure to keep constant LUN IDs for RDMs across all collaborating hosts.
Each host must meet the networking necessities
Configure a VMkernel port on every host.
Dedicate as a minimum one GigE adapter for vMotion.
Use at the least one 10 GigE adapter in case you migrate workloads which have many memory operations.
Use jumbo frames for satisfactory vMotion overall performance.
Ensure that jumbo frames are enabled on all network gadgets which are on the vMotion route together with physical NICs, bodily switches and virtual switches.
Question 7. What Is The Difference Between Clone And Template In Vmware?

Answer :

Clone

A clone is a copy of digital device.
You can't convert returned the cloned Virtual Machine.
A Clone of a Virtual Machine may be created whilst the Virtual Machine is powered on
Cloning may be executed in  methods specifically Full Clone and Linked Clone.
A full clone is an unbiased reproduction of a virtual system that shares nothing with the figure virtual gadget after the cloning operation. Ongoing operation of a full clone is completely break away the parent digital gadget.
A connected clone is a copy of a virtual system that shares digital disks with the figure virtual device in an ongoing way. This conserves disk space, and lets in multiple digital machines to apply the identical software program set up.
Cloning a virtual device can store time in case you are deploying many similar virtual machines. You can create, configure, and install software on a unmarried virtual gadget, after which clone it a couple of times, instead of growing and configuring every digital machine for my part.
Template

A template is a master replica or a baseline photograph of a virtual gadget that can be used to create many clones.
Templates cannot be powered on or edited, and are extra tough to regulate than regular digital machine.
You can convert the template lower back to Virtual Machine to update the base template with the modern released patches and updates and to install or improve any software program and again convert returned to template for use for destiny deployment of Virtual Machines with the modern-day patches.
Convert digital Machine to template can't be accomplished, while Virtual device is powered on.  Only Clone to Template may be carried out whilst the Virtual Machine is powered on.
A template offers a extra comfortable way of preserving a digital gadget configuration which you need to set up many times.
When you clone a virtual device or install a virtual machine from a template, the resulting cloned virtual machine is independent of the unique digital machine or template.
Citrix NetScaler Interview Questions
Question eight. What Is Promiscuous Mode In Vmware?

Answer :

Promiscuous mode is a safety policy which may be defined on the virtual transfer or portgroup level
A virtual device, Service Console or VMkernel community interface in a portgroup which permits use of promiscuous mode can see all network traffic traversing the digital transfer.
If this mode is about to reject, the packets are despatched to meant port so that the meant digital system will only be capable of see the communique.
Example: In case you're using a digital xp inside any Windows VM. If promiscuous mode is ready to reject then the virtual xp may not be able to join the network except promiscuous mode is enabled for the Windows VM.
Question 9. What Is The Difference Between Thick Provision Lazy Zeroed, Thick Provision Eager Zeroed And Thin Provision?

Answer :

Thick Provision Lazy Zeroed

Creates a digital disk in a default thick format.
Space required for the virtual disk is allotted while the virtual disk is created.
Data ultimate at the physical tool is not erased in the course of advent, however is zeroed out on call for at a later time on first write from the virtual system.
Using the default flat virtual disk layout does now not 0 out or cast off the possibility of recovering deleted files or restoring vintage facts that is probably gift in this allotted area.
You can not convert a flat disk to a skinny disk.
Thick Provision Eager Zeroed

A form of thick virtual disk that supports clustering features inclusive of Fault Tolerance.
Space required for the digital disk is allocated at introduction time.
In assessment to the flat format, the records final on the bodily tool is zeroed out while the digital disk is created.
It may take an awful lot longer to create disks in this layout than to create other types of disks.
Thin Provision

It affords on on-call for allocation of blocks of statistics.
All the distance allocated on the time of introduction of digital disk is not applied at the difficult disk, as an alternative best the size with applied information is locked and the scale increases as the amount of statistics is extended on the disk.
With skinny provisioning, garage ability usage efficiency may be robotically pushed up toward 100% with very little administrative overhead.
VMware ESXi Interview Questions
Question 10. What Is A Snapshot?

Answer :

A photo is a “factor in time photo” of a virtual visitor operating gadget (VM). That image includes an image of the VMs disk, RAM, and gadgets at the time the image became taken. With the snapshot, you could return the VM to that factor in time, every time you select. You can take snapshots of your VMs, regardless of what guest OS you've got and the image capability can be used for capabilities like acting photo stage backups of the VMs with out ever shutting them down.

Question eleven. What Is Vdi?

Answer :

VDI stands for Virtual Desktop Infrastructure where end user bodily device like computing device or computer are virtualized due to which VMware defined VDI as "delivering computer systems from the records center”.
Once VDI is used the end consumer hook up with their laptop the usage of a device called thin purchaser.
The give up consumer also can hook up with their desktop the use of VMware Horizon View set up on any computing device or mobile gadgets
Microsoft Virtual Server Interview Questions
Question 12. What Is Vmware Ha?

Answer :

VMware HA i.E. High Availability which works at the host stage and is configured at the Cluster.
A Cluster configured with HA will migrate and restart all the vms jogging beneath any of the host in case of any host-level failure routinely to any other host below the same cluster.
VMware HA continuously monitors all ESX Server hosts in a cluster and detects screw ups.
VMware HA agent located on every host maintains a heartbeat with the other hosts inside the cluster the usage of the carrier console community. Each server sends heartbeats to the others servers in the cluster at 5-2nd periods. If any servers lose heartbeat over three consecutive heartbeat periods, VMware HA initiates the failover motion of restarting all affected virtual machines on other hosts.
You can set virtual device restart priority in case of any host failure depending upon the critical nature of the vm.
NOTE: Using HA in case of any host failure with RESTART the vms on different host so the vms nation can be interrupted and it is not a stay migration

Hyper-V Interview Questions
Question 13. What Is The Difference Between Vmware Ha And Vmotion?

Answer :

VMware HA is used inside the event while any of the hosts inner a cluster fails then all the virtual machines strolling beneath it are restarted on specific host inside the equal cluster.

Now HA is depending on vMotion to perform stay migration of the vms to unique host so vMotion is just used for the migration cause between multiple hosts which is also used by different functionality like DRS.

NOTE: Anyhow HA can work very will with out vMotion as its primary capability is to restart the vm from the affected host to the working host however this will be provider affecting because the vms will be 'powered off' and then 'powered on' on the brand new host.

Question 14. What Is Storage Vmotion?

Answer :

Storage vMotion is just like vMotion in the experience that "some thing" associated with the VM is moved and there may be no downtime to the VM visitor and end customers. However, with SVMotion the VM Guest stays on the server that it is living on but the digital disk for that VM is what actions.
With Storage vMotion, you may migrate a digital system and its disk files from one datastore to any other even as the digital machine is jogging.
You can select to place the virtual machine and all its disks in a single vicinity, or select separate places for the virtual system configuration document and every digital disk.
During a migration with Storage vMotion, you may transform digital disks from Thick-Provisioned Lazy Zeroed or Thick-Provisioned Eager Zeroed to Thin-Provisioned or the reverse.
Perform live migration of virtual system disk files across any Fibre Channel, iSCSI, FCoE and NFS garage
Question 15. What Is Vmware Drs And How Does It Works?

Answer :

Here DRS stands for Distributed Resource Scheduler which dynamically balances useful resource across numerous host underneath Cluster or useful resource pool.
VMware DRS permits customers to define the guidelines and guidelines that decide how digital machines share sources and how those sources are prioritized among more than one digital machines.
Resources are allotted to the virtual machine with the aid of both migrating it to any other server with greater available resources or through making more “space” for it on the equal server by using migrating other virtual machines to distinctive servers.
The live migration of digital machines to different physical servers is accomplished completely transparent to quit-customers via VMware VMotion
VMware DRS can be configured to function in both computerized or guide mode. In computerized mode, VMware DRS determines the nice possible distribution of digital machines amongst special physical servers and robotically migrates digital machines to the most appropriate physical servers. In manual mode, VMware DRS presents a advice for most appropriate placement of digital machines, and leaves it to the system administrator to determine whether to make the change.
VMware NSX Interview Questions
Question 16. What Is Vmware Fault Tolerance?

Answer :

VMware Fault Tolerance offers non-stop availability to applications strolling in a virtual device, preventing downtime and records loss inside the occasion of server failures.
VMware Fault Tolerance, when enabled for a digital system, creates a live shadow example of the number one, strolling on every other physical server.
The two instances are stored in virtual lockstep with every different the use of VMware vLockstep generation
The two virtual machines play the precise same set of occasions, because they get the exact identical set of inputs at any given time.
The  virtual machines constantly heartbeat towards every other and if either digital system example loses the pulse, the other takes over immediately. The heartbeats are very frequent, with millisecond intervals, making the failover immediate and not using a lack of statistics or state.
VMware Fault Tolerance requires a devoted community connection, break free the VMware VMotion network, among the 2 physical servers.
Question 17. In A Cluster With More Than 3 Hosts, Can You Tell Fault Tolerance Where To Put The Fault Tolerance Virtual Machine Or Does It Chose On Its Own?

Answer :

You can place the original (or Primary digital system). You have full manipulate with DRS or vMotion to assign it to any node. The placement of the Secondary, when created, is automated based at the available hosts. But whilst the Secondary is created and positioned, you could vMotion it to the favored host.

Advanced Linux Interview Questions
Question 18. How Many Virtual Cpus Can I Use On A Fault Tolerant Virtual Machine ?

Answer :

vCenter Server 4.X and vCenter Server 5.X guide 1 digital CPU in line with blanketed virtual device.

Red Hat Linux System Administration Interview Questions
Question 19. What Happens If Vcenter Server Is Offline When A Failover Event Occurs?

Answer :

When Fault Tolerance is configured for a virtual machine, vCenter Server want now not be on-line for FT to paintings. Even if vCenter Server is offline, failover nevertheless takes place from the Primary to the Secondary virtual gadget. Additionally, the spawning of a brand new Secondary digital gadget additionally happens with out vCenter Server.

Question 20. What Is The Difference Between Type 1 And Type 2 Hypervisor?

Answer :

Type 1 Hypervisor

This is also known as Bare Metal or Embedded or Native Hypervisor.
It works directly at the hardware of the host and might display operating systems that run above the hypervisor.
It is absolutely impartial from the Operating System.
The hypervisor is small as its fundamental mission is sharing and coping with hardware sources between different working systems.
A principal gain is that any issues in a single virtual system or guest operating machine do no longer have an effect on the opposite guest running systems jogging at the hypervisor.
Examples: VMware ESXi Server, Microsoft Hyper-V, Citrix/Xen Server
Type 2 Hypervisor

This is likewise known as Hosted Hypervisor.
In this situation, the hypervisor is established on an operating gadget and then helps other operating structures above it.
It is absolutely depending on host Operating System for its operations
While having a base running system permits better specification of regulations, any problems inside the base running gadget a ffects the complete gadget as nicely even though the hypervisor walking above the base OS is secure.
Examples: VMware Workstation, Microsoft Virtual PC, Oracle Virtual Box
VMware Interview Questions
Question 21. How Does Vsphere Ha Works?

Answer :

When we configure a couple of hosts for HA cluster, a single host is robotically elected because the master host. The grasp host communicates with vCenter Server and monitors the state of all blanketed virtual machines and of the slave hosts. When you add a number to a vSphere HA cluster, an agent is uploaded to the host and configured to speak with different dealers within the cluster.

Question 22. What Are The Monitoring Methods Used For Vsphere Ha?

Answer :

The Master and Slave hosts uses  sorts of monitoring the fame of the hosts

Datastore Heartbeat
Network Heartbeat
Question 23. What Are The Roles Of Master Host In Vsphere Ha?

Answer :

Monitoring the kingdom of slave hosts. If a slave host fails or turns into unreachable, the master host identifies which virtual machines want to be restarted.
Monitoring the electricity country of all blanketed digital machines. If one digital system fails, the grasp host guarantees that it's far restarted. Using a nearby placement engine, the master host also determines wherein the restart have to be achieved.
Managing the lists of cluster hosts and protected digital machines.
Acting as vCenter Server control interface to the cluster and reporting the cluster health nation.
Vmware Vsphere Interview Questions
Question 24. How Is A Master Host Elected In Vsphere Ha Environment?

Answer :

When vSphere HA is enabled for a cluster, all active hosts (the ones now not in standby or protection mode, or no longer disconnected) participate in an election to pick out the cluster's master host. The host that mounts the finest number of datastores has a bonus inside the election. Only one master host normally exists per cluster and all different hosts are slave hosts.

If the master host fails, is close down or installed standby mode, or is eliminated from the cluster a new election is held.

Citrix NetScaler Interview Questions
Question 25. If The Vcenterserver Goes Down With A Situation That It Was Pre Configured With Vsphere Ha And Drs, So After Power Down Will Ha And Drs Perform Their Task?

Answer :

vSphere HA isn't always dependent on vCenterserver for its operations as whilst HA is configured it installs an agent into each host which does its element and isn't dependent on vCenterserver. Also HA doesnot makes use of vMotion, it justs restarts the vms into some other host anyways of host failure.

Further vSphere DRS could be very a whole lot depending on vCenterserver because it uses vMotion for its action for stay migration of vms among a couple of hosts so in case vCenterserver goes down the vMotion might not paintings leading to failure of DRS.

Question 26. What Is The Use Of Vmware Tools?

Answer :

VMware Tools is a set of utilities that enhances the performance of the digital machine's guest operating device and improves management of the virtual gadget. Without VMware Tools hooked up to your visitor working gadget, guest overall performance lacks crucial capability. Installing VMware Tools eliminates or improves these issues:

Low video decision
Inadequate color depth
Incorrect show of network speed
Restricted movement of the mouse
Inability to replicate and paste and drag-and-drop documents
Missing sound
Provides the ability to take quiesced snapshots of the guest OS
Synchronizes the time in the guest operating system with the time on the host
Provides support for visitor-bound calls created with the VMware VIX API
Vmware Horizon Interview Questions