Interview Questions.

Q1. What Is Vmware Vmotion And What Are Its Requirements?

VMware VMotion allows the stay migration of going for walks digital machines from one physical server to some other with 0 downtime.

VMotion lets you:

Automatically optimize and allocate entire pools of assets for optimum hardware utilization and  availability.

Perform hardware upkeep without any scheduled downtime.

Proactively migrate virtual machines faraway from failing or under acting servers.

Below are the pre-standards for configuring vMotion :

Each host need to be successfully licensed for vMotion

Each host have to meet shared garage requirements

vMotion migrates the vm from one host to every other that is best possible with each the host are sharing a common garage or to any garage accessible by each the source and goal hosts. 

A shared garage can be on a Fibre Channel storage vicinity community (SAN), or may be carried out using iSCSI SAN and NAS.

If you use vMotion emigrate virtual machines with raw device mapping (RDM) files, ensure to keep regular LUN IDs for RDMs across all collaborating hosts.

Each host must meet the networking requirements

Configure a VMkernel port on each host.

Dedicate at least one GigE adapter for vMotion.

Use as a minimum one 10 GigE adapter if you migrate workloads that have many memory operations.

Use jumbo frames for pleasant vMotion overall performance.

Ensure that jumbo frames are enabled on all network gadgets which can be on the vMotion direction together with physical NICs, bodily switches and digital switches.

Q2. What Is The Difference Between Thick Provision Lazy Zeroed, Thick Provision Eager Zeroed And Thin Provision?

Thick Provision Lazy Zeroed

Creates a virtual disk in a default thick format.

Space required for the digital disk is allocated whilst the digital disk is created.

Data remaining at the physical device isn't always erased throughout advent, but is zeroed out on demand at a later time on first write from the digital gadget.

Using the default flat digital disk format does no longer zero out or dispose of the opportunity of recovering deleted documents or restoring old records that might be present on this allocated space.

You can not convert a flat disk to a skinny disk.

Thick Provision Eager Zeroed

A kind of thick digital disk that supports clustering capabilities which includes Fault Tolerance.

Space required for the virtual disk is allotted at creation time.

In evaluation to the flat layout, the statistics closing at the bodily device is zeroed out when the virtual disk is created.

It may take much longer to create disks in this layout than to create different sorts of disks.

Thin Provision

It provides on on-demand allocation of blocks of data.

All the gap allotted at the time of advent of virtual disk isn't always applied on the difficult disk, as an alternative simplest the size with applied information is locked and the scale will increase as the amount of information is extended at the disk.

With thin provisioning, garage capacity usage performance may be routinely driven up in the direction of 100% with very little administrative overhead.

Q3. How Does Vsphere Ha Works?

When we configure multiple hosts for HA cluster, a unmarried host is mechanically elected because the grasp host. The grasp host communicates with vCenter Server and video display units the nation of all included digital machines and of the slave hosts. When you upload a number to a vSphere HA cluster, an agent is uploaded to the host and configured to talk with other retailers in the cluster.

Q4. What Is A Hypervisor?

It is a application that allows a couple of operating systems to share a unmarried hardware host. Each working system appears to have the host's processor, memory, and other assets all to itself. However, the hypervisor is clearly controlling the host processor and assets, allocating what is wanted to every running gadget in turn and making sure that the visitor working structures (called virtual machines) can not disrupt each other.

Q5. What Is Vdi?

VDI stands for Virtual Desktop Infrastructure where stop consumer physical system like computing device or pc are virtualized due to which VMware defined VDI as "handing over computer systems from the facts center”.

Once VDI is used the stop person connect to their laptop the usage of a tool referred to as thin consumer.

The end consumer can also connect with their computing device the usage of VMware Horizon View installed on any desktop or cell devices

Q6. What Is The Difference Between Type 1 And Type 2 Hypervisor?

Type 1 Hypervisor:

This is also called Bare Metal or Embedded or Native Hypervisor.

It works at once at the hardware of the host and might reveal working systems that run above the hypervisor.

It is absolutely unbiased from the Operating System.

The hypervisor is small as its most important assignment is sharing and dealing with hardware assets between one-of-a-kind operating systems.

A predominant benefit is that any troubles in a single digital machine or guest working system do no longer affect the opposite guest running structures jogging on the hypervisor.

Examples: VMware ESXi Server, Microsoft Hyper-V, Citrix/Xen Server

Type 2 Hypervisor :

This is likewise referred to as Hosted Hypervisor.

In this situation, the hypervisor is established on an working machine after which supports different working structures above it.

It is completely dependent on host Operating System for its operations

While having a base running device allows higher specification of rules, any problems inside the base working machine a ffects the whole gadget as nicely even though the hypervisor strolling above the bottom OS is at ease.

Examples: VMware Workstation, Microsoft Virtual PC, Oracle Virtual Box

Q7. What Is The Difference Between Vmware Ha And Vmotion?

VMware HA is used inside the occasion whilst any of the hosts internal a cluster fails then all of the virtual machines going for walks underneath it are restarted on special host inside the equal cluster.

Now HA is dependent on vMotion to carry out stay migration of the vms to extraordinary host so vMotion is just used for the migration reason between multiple hosts which is also used by other functionality like DRS.

NOTE: Anyhow HA can work very will without vMotion as its number one functionality is to restart the vm from the affected host to the running host but this could be provider affecting as the vms will be 'powered off' after which 'powered on' on the brand new host.

Q8. How Is A Master Host Elected In Vsphere Ha Environment?

When vSphere HA is enabled for a cluster, all energetic hosts (those now not in standby or maintenance mode, or not disconnected) participate in an election to select the cluster's master host. The host that mounts the best number of datastores has an advantage inside the election. Only one grasp host typically exists according to cluster and all other hosts are slave hosts.

If the grasp host fails, is close down or installed standby mode, or is removed from the cluster a brand new election is held.

Q9. In A Cluster With More Than three Hosts, Can You Tell Fault Tolerance Where To Put The Fault Tolerance Virtual Machine Or Does It Chose On Its Own?

You can area the unique (or Primary digital system). You have full manipulate with DRS or vMotion to assign it to any node. The placement of the Secondary, whilst created, is automated primarily based on the available hosts. But whilst the Secondary is created and located, you could vMotion it to the desired host.

Q10. If The Vcenter Server Goes Down With A Situation That It Was Pre Configured With Vsphere Ha And Drs, So After Power Down Will Ha And Drs Perform Their Task?

VSphere HA isn't always depending on vCenterserver for its operations as when HA is configured it installs an agent into every host which does its element and is not dependent on vCenterserver. Also HA doesnot uses vMotion, it justs restarts the vms into another host in any case of host failure.

Further vSphere DRS is very a lot depending on vCenterserver as it uses vMotion for its motion for live migration of vms among a couple of hosts so in case vCenterserver goes down the vMotion may not work main to failure of DRS.

Q11. What Is Promiscuous Mode In Vmware?

Promiscuous mode is a safety policy which can be described on the digital switch or portgroup stage

A digital machine, Service Console or VMkernel network interface in a portgroup which allows use of promiscuous mode can see all community site visitors traversing the virtual transfer.

If this mode is about to reject, the packets are sent to supposed port in order that the supposed virtual system will simplest be able to see the verbal exchange.

Example: In case you're the usage of a virtual xp internal any Windows VM. If promiscuous mode is about to reject then the virtual xp won't be capable of connect the community except promiscuous mode is enabled for the Windows VM.

Q12. What Is Vmware Ha?

VMware HA i.E. High Availability which fits on the host level and is configured on the Cluster.

A Cluster configured with HA will migrate and restart all the vms jogging underneath any of the host in case of any host-level failure mechanically to another host below the equal cluster.

VMware HA continuously video display units all ESX Server hosts in a cluster and detects screw ups.

VMware HA agent positioned on each host keeps a heartbeat with the other hosts in the cluster using the carrier console community. Each server sends heartbeats to the others servers in the cluster at five-second durations. If any servers lose heartbeat over three consecutive heartbeat periods, VMware HA initiates the failover action of restarting all affected virtual machines on other hosts.

You can set virtual machine restart precedence in case of any host failure depending upon the vital nature of the vm.

NOTE: Using HA in case of any host failure with RESTART the vms on special host so the vms state will be interrupted and it is not a live migration

Q13. What Is The Use Of Vmware Tools?

VMware Tools is a suite of utilities that enhances the performance of the virtual system's guest working system and improves management of the virtual gadget. Without VMware Tools set up for your guest running gadget, visitor overall performance lacks crucial capability.

Installing VMware Tools eliminates or improves those troubles:

Low video resolution

Inadequate shade intensity

Incorrect show of network velocity

Restricted motion of the mouse

Inability to duplicate and paste and drag-and-drop documents

Missing sound

Provides the capacity to take quiesced snapshots of the visitor OS

Synchronizes the time in the guest running system with the time on the host

Provides guide for visitor-certain calls created with the VMware VIX API

Q14. What Is Vmware Drs And How Does It Works?

Here DRS stands for Distributed Resource Scheduler which dynamically balances resource throughout numerous host underneath Cluster or aid pool:

VMware DRS permits users to define the rules and rules that decide how digital machines percentage sources and the way those resources are prioritized amongst a couple of digital machines.

Resources are allocated to the virtual gadget by means of either migrating it to another server with greater available sources or through making greater “space” for it at the equal server with the aid of migrating other digital machines to unique servers.

The stay migration of digital machines to different physical servers is carried out completely transparent to end-customers through VMware VMotion

VMware DRS may be configured to function in both automated or manual mode. In automatic mode, VMware DRS determines the excellent feasible distribution of virtual machines among extraordinary physical servers and routinely migrates digital machines to the most suitable physical servers. In guide mode, VMware DRS gives a advice for most excellent placement of virtual machines, and leaves it to the system administrator to determine whether or not to make the change.

Q15. What Are The Monitoring Methods Used For Vsphere Ha?

The Master and Slave hosts uses  types of monitoring the reputation of the hosts

Datastore Heartbeat

Network Heartbeat

Q16. What Happens If Vcenter Server Is Offline When A Failover Event Occurs?

When Fault Tolerance is configured for a virtual device, vCenter Server want not be online for FT to work. Even if vCenter Server is offline, failover still takes place from the Primary to the Secondary virtual gadget. Additionally, the spawning of a brand new Secondary digital device additionally happens without vCenter Server.

Q17. What Is Storage Vmotion?

Storage vMotion is just like vMotion inside the feel that "something" related to the VM is moved and there is no downtime to the VM guest and give up users. However, with SVMotion the VM Guest stays on the server that it is living on however the digital disk for that VM is what moves.

With Storage vMotion, you may migrate a digital system and its disk files from one datastore to another at the same time as the digital system is walking.

You can select to place the virtual system and all its disks in a single region, or select separate locations for the virtual gadget configuration file and each virtual disk.

During a migration with Storage vMotion, you may rework digital disks from Thick-Provisioned Lazy Zeroed or Thick-Provisioned Eager Zeroed to Thin-Provisioned or the opposite.

Perform stay migration of virtual gadget disk documents throughout any Fibre Channel, iSCSI, FCoE and NFS garage

Q18. What Is The Difference Between The Vsphere Esx And Esxi Architectures?

VMware ESX and ESXi are both naked steel hypervisor architectures that installation without delay at the server hardware.

Although neither hypervisor architectures relies on an OS for aid management, the vSphere ESX structure relied on a Linux working machine, referred to as the Console OS (COS) or provider console, to carry out  control features: executing scripts and installing third-birthday party marketers 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 floor” and much less code to patch, improving reliability and protection.

Q19. What Is Vmware Fault Tolerance?

VMware Fault Tolerance offers continuous availability to applications going for walks in a virtual system, stopping downtime and information loss in the occasion of server disasters.

VMware Fault Tolerance, while enabled for a virtual system, creates a live shadow example of the number one, strolling on another bodily server.

The  instances are stored in virtual lockstep with each other the usage of VMware vLockstep era

The  digital machines play the exact identical set of occasions, because they get the precise same set of inputs at any given time.

The  virtual machines continuously heartbeat against each other and if either virtual gadget instance loses the heartbeat, the alternative takes over straight away. The heartbeats are very common, with millisecond intervals, making the failover immediate and not using a loss of facts or nation.

VMware Fault Tolerance requires a committed community connection, cut loose the VMware VMotion community, between the two physical servers.

Q20. What Is A Snapshot?

A snapshot is a “factor in time photo” of a virtual guest working device (VM). That picture contains an photo of the VMs disk, RAM, and gadgets at the time the snapshot became taken. With the snapshot, you may return the VM to that point in time, whenever you pick out. You can take snapshots of your VMs, irrespective of what visitor OS you have got and the snapshot functionality can be used for capabilities like acting image degree backups of the VMs with out ever shutting them down.

Q21. How Many Virtual Cpus Can I Use On A Fault Tolerant Virtual Machine ?

VCenter Server 4.X and vCenter Server 5.X assist 1 virtual CPU in line with covered virtual device.

Q22. What Are The Different Types Of Virtualization?

Server Virtualization – consolidating more than one physical servers into digital servers that run on a single bodily server.

Application Virtualization – an application runs on every other host from wherein it is hooked up in a variety of approaches. It could be achieved through software streaming, computer virtualization or VDI, or a VM package (like VMware ACE creates with a participant). Microsoft Softgrid is an instance of Application virtualization.

Presentation Virtualization – This is what Citrix Met frame (and the ICA protocol) as well as Microsoft Terminal Services (and RDP) are capable of create. With presentation virtualization, an software truely runs on some other host and all that you see at the client is the display screen from wherein it's far run.

Network Virtualization – with network virtualization, the community is “carved up” and can be used for more than one purposes inclusive of going for walks a protocol analyzer interior an Ethernet switch. Components of a digital community could include NICs, switches, VLANs, network storage devices, virtual network bins, and community media.

Storage Virtualization – with storage virtualization, the disk/statistics garage to your facts is consolidated to and managed by means of a virtual storage device. The servers related to the storage gadget aren’t aware of where the information clearly is. Storage virtualization is now and again described as “abstracting the logical garage from the bodily storage.

Q23. What Is A .Vmdk File?

This isn't always the record containing the uncooked records. Instead it is the disk descriptor record which describes the size and geometry of the digital disk document. This file is in text layout and carries the call of the –flat.Vmdk file for which it is associated with and additionally the difficult force adapter kind, pressure sectors, heads and cylinders, and so forth. One of those documents will exist for each virtual tough power that is assigned for your digital machine. You can tell which –flat.Vmdk report it is related to by commencing the file and searching at the Extent Description discipline.

Q24. What Are The Roles Of Master Host In Vsphere Ha?

Monitoring the kingdom of slave hosts. If a slave host fails or becomes unreachable, the grasp host identifies which virtual machines want to be restarted.

Monitoring the electricity state of all included virtual machines. If one digital device fails, the master host ensures that it is restarted. Using a nearby placement engine, the grasp host also determines in which the restart ought to be achieved.

Managing the lists of cluster hosts and guarded digital machines.

Acting as vCenter Server management interface to the cluster and reporting the cluster health country.

Q25. What Is The Difference Between Clone And Template In Vmware?

Clone

A clone is a replica of virtual gadget.

You can't convert again the cloned Virtual Machine.

A Clone of a Virtual Machine may be created when the Virtual Machine is powered on

Cloning may be performed in two methods specifically Full Clone and Linked Clone.

A full clone is an impartial reproduction of a digital system that shares nothing with the determine virtual gadget after the cloning operation. Ongoing operation of a full clone is entirely become independent from the parent digital machine.

A related clone is a replica of a digital device that stocks virtual disks with the figure digital machine in an ongoing way. This conserves disk space, and allows more than one virtual machines to use the same software program set up.

Cloning a virtual device can save time in case you are deploying many comparable digital machines. You can create, configure, and set up software on a unmarried digital system, after which clone it multiple times, instead of growing and configuring each digital gadget individually.

Template

A template is a master copy or a baseline picture of a digital machine that can be used to create many clones.

Templates cannot be powered on or edited, and are greater hard to regulate than regular virtual machine.

You can convert the template back to Virtual Machine to update the bottom template with the state-of-the-art launched patches and updates and to put in or upgrade any software program and once more convert lower back to template to be used for future deployment of Virtual Machines with the trendy patches.

Convert digital Machine to template can not be accomplished, when Virtual gadget is powered on.  Only Clone to Template may be achieved whilst the Virtual Machine is powered on.

A template gives a greater relaxed manner of keeping a virtual gadget configuration that you need to installation usually.

When you clone a virtual gadget or set up a digital gadget from a template, the ensuing cloned digital device is impartial of the unique virtual gadget or template.