VMware is the leader in Virtualization and Cloud Computing technologies and also providing solutions in the field of network and desktop virtualization. VMware has changed the tech world from physical to software based virtual world.
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Due to implementation of virtual environment to consolidate the available hardware, the demands of subject matter experts are increasing day by day in the market. To manage and maintain organization’s business, an experience workforce is required, and to choose the top talent from the market for growing an organization’s business, professionals are selected via many technical interviews and HR processes.
Along with the HR processes, technical interviews are also conducted to assess the abilities of a professional in the field of virtualization for continues business process. Here are 80 interview questions on data center virtualization technology fresher and up to 3 years of hands-on experience that may be asked to assess the candidate’s technical and hands-on expertise.
These interview questions are categorized into following technical areas:
- Hypervisor
- Fault Tolerance (FT)
- Virtual Networking
- vCenter Server
- Virtual Storage (Datastore)
- What’s New in vSphere 6.0
- Content Libraries
- vSAN
- vApp and
- Miscellaneous
Hypervisor
- What is VMKernel and why it is important?
VMkernel is a virtualization interface between a Virtual Machine and the ESXi host which stores VMs. It is responsible to allocate all available resources of ESXi host to VMs such as memory, CPU, storage etc. It’s also control special services such as vMotion, Fault tolerance, NFS, traffic management and iSCSI. To access these services, VMkernel port can be configured on ESXi server using a standard or distributed vSwitch. Without VMkernel, hosted VMs cannot communicate with ESXi server.
- What is hypervisor and its types?
Hypervisor is a virtualization layer that enables multiple operating systems to share a single hardware host. Each operating system or VM is allocated physical resources such as memory, CPU, storage etc by the host. There are two types of hypervisors
- Hosted hypervisor (works as application i-e VMware Workstation)
- Bare-metal (is virtualization software i-e VMvisor, hyper-V which is installed directly onto the hardware and controls all physical resources).
- What is Virtualization?
The process of creating virtual versions of physical components i-e Servers, Storage Devices, Network Devices on a physical host is called virtualization. Virtualization lets you run multiple virtual machines on a single physical machine which is called ESXi host.
- What are different types of virtualization?
There are 5 basic types of virtualization
- Server virtualization: consolidates the physical server and multiple OS can be run on a single server.
- Network Virtualization: Provides complete reproduction of physical network into a software defined network.
- Storage Virtualization: Provides an abstraction layer for physical storage resources to manage and optimize in virtual deployment.
- Application Virtualization: increased mobility of applications and allows migration of VMs from host on another with minimal downtime.
- Desktop Virtualization: virtualize desktop to reduce cost and increase service
Fault Tolerance (FT)
- What is VMware FT?
FT stands for Fault Tolerance very prominent component of VMware vSphere. It provides continuous availability for VMs when an ESXi host fails. It supports up to 4 vCPUs and 64 GB memory. FT is very bandwidth intensive and 10GB NIC is recommended to configure it. It creates complete copy of an entire VM such as storage, compute, and memory.
- How many vCPUs can be used for a VM in FT?
In vSphere 6.0, there can be up to 4 vCPUs and 64 GB RAM can be used.
- What is the name of the technology used by VMware FT?
vLockstep technology is used by VMware FT
- What is Fault Tolerant Logging?
The communication between two ESXi host is called FT logging when FT is configured between them. The pre-requisition of configuring FT is to configure VMKernel port.
- Will the FT work if vCenter Server goes down?
vCenter server is only required to enable Fault Tolerance on a VM. Once it is configured, vCenter is not required to be in online for FT to work. FT failover between primary and secondary will occur even if the vCenter is down.
- What is main difference between VMware HA and FT?
Main difference between VMware HA and FT is: HA is enabled per cluster and VMware FT is enabled per VM. In HA, VMs will be re-started and powered-on on another host in case of host failure, while in FT there is no downtime, because second copy will be activated in case of host failure.
Virtual Networking
- What is virtual networking?
A network of VMs running on a physical server that are connected logically with each other is called virtual networking.
- What is vSS?
vSS stands for Virtual Standard Switch is responsible for communication of VMs hosted on a single physical host. it works like a physical switch automatically detects a VM which want to communicate with other VM on a same physical server.
- What is vDS?
vDS stands for Virtual Distributed Switch acts as a single switch in whole virtual environment and is responsible to provide central provisioning, administration, and monitoring of virtual network.
- How many maximum standard ports per host available?
4096 ports per host are available either in standard switch or distributed switch.
- What are main benefits of distributed switch (vDS)?
vDS can provide:
- Central administration for a data center
- Central provision, and
- Monitoring
- What is VMKernal adapter and why it used?
VMKernel adapter provides network connectivity to the ESXi host to handle network traffic for vMotion, IP Storage, NAS, Fault Tolerance, and vSAN. For each type of traffic such as vMotion, vSAN etc. separate VMKernal adapter should be created and configured.
- What are main use of port groups in data center virtualization?
You can segregate the network traffic by using port groups such as vMotion, FT, management traffic etc.
- What are three port groups are configured in ESXi networking?
- Virtual Machine Port Group – Used for Virtual Machine Network
- Service Console Port Group – Used for Service Console Communications
- VMKernel Port Group – Used for VMotion, iSCSI, NFS Communications
- What is VLAN and why use in virtual networking?
A logical configuration on the switch port to segment the IP Traffic where each segment cannot communicate with other segment without proper rules mentioned is called VLAN and every VLAN has a proper number called VLAN ID.
- What is VLAN Tagging?
The practice of inserting VLAN ID into a packet header to identify which VLAN packet belongs to is called VLAN tagging.
- What are three network security policies/modes on vSwitch?
- Promiscuous mode
- MAC address change
- Forged transmits
- What is promiscuous mode on vSwitch?
The default mode is Reject. If Accept is selected, VM will receive all traffic port group via vSwitch.
- What is MAC address changes network policy?
The default mode of this policy is Reject. If the Accept is selected, host will accept requests to change the effective MAC address.
- What is Forged transmits network policy?
The default mode is Reject. If Accept is selected, host will not compare the source and effective MAC address transmitted from a VM.
vCenter Server
- What are main components of vCenter Server architecture?
There are three main components of vCenter Server architecture.
- vSphere Client and Web Client: a user interface.
- vCenter Server database: SQL server or embedded PostgreSQL to store inventory, security roles, resource pools etc.
- SSO: a security domain in virtual environment
- What is PSC and its components?
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
- What are two main deploying methods of PSC
You can install PSC in two ways:
- What are different types of vCenter Server deployment?
It has two deployment types
- Embedded deployment
- External deployment
- What is vRealize Operation (vROP)
vROP provides the operation dashboards for performance analytics, capacity optimization and monitoring the virtual environment.
- What is the basic security step to secure vCenter Server and users?
Authenticate vCenter Server with Active Directory. By using this we can assign specific roles to users and can also manage virtual environment in an efficient way.
Virtual Storage (Datastore)
- What is datastore?
Datastore is a storage location where virtual machine files are stored and accessed. Datastore is based on a file system which is called VMFS, NFS.
- What is the .vmx file?
It is the configuration file of a VM
- What information .nvram file stores?
It stores BIOS related information of a VM.
- What .vmdk file does and used?
Vmdk is a VM disk file and stores data of a VM. It can be up to 62 TB in size in vSphere 6.0 version.
- How many disk types are in VMware?
There are three disk types in vSphere.
- Thick Provisioned Lazy Zeroes: every virtual disk is created by default in this disk format. Physical space is allocated to a VM when virtual disk is created. It can’t be converted to thin disk.
- Thick Provision Eager Zeroes: this disk type is used in VMware Fault Tolerance. All required disk space is allocated to a VM at time of creation. It takes more time to create a virtual disk compare to other disk formats.
- Thin provision: It provides on-demand allocation of disk space to a VM. When data size grows, the size of disk will grow. Storage capacity utilization can be up to 100% with thin provisioning.
- What is Storage vMotion?
It is similar to traditional vMotion, in Storage vMotion, virtual disk of a VM is moved from datastore to another. During Storage vMotion, virtual disk types think provisioning disk can be transformed to thin provisioned disk.
What’s New in vSphere 6.0
- What is VM Hardware version for vSphere 6.0?
Version 11
- What VM hardware version for vSphere 6.5?
Version 13
- In which version of vSphere PSC was introduce?
Platform Services Controller (PSC) is introduced in vSphere 6.0. vSphere 6.0 is also known as Virtual hardware version 11.
- How many maximum hosts can manage a vCenter Server in vSphere 6.0?
In vSphere 6.0, a single vCenter Server can manage up to 1000 hosts either in Windows or in vCenter Appliance (vCSA).
- How many hosts can be managed by a cluster in vSphere 6.0?
A single cluster can manage maximum 64 hosts
- How maximum VMs can be managed by a single cluster?
A single cluster can manage maximum of 8000 VMs.
- What is VVol?
Virtual Volume a new VM disk management concept introduced in vSphere 6.0 that enables array-based operations at the virtual disk level. VVol is automatically created when virtual disk is created in virtual environment for a VM.
- How many licensing options for vSphere 6.0?
There are three licensing options for vSphere 6.0:
- Standard Edition: Contains 1 vCenter Server Standard license, up to 2 vCPUs for Fault Tolerance, vMotion, Storage vMotion, HA, VVols etc.
- Enterprise Edition: Same as Standard Edition additionally APIs for Array Integration and Multipathing, DRS, and DPM.
- Enterprise Plus: Includes all features of Standard and Enterprise Editions with additionally Fault Tolerance upto 4 vCPUs and 64GB of RAM. It also includes Distributed vSwitch and the most expensive licensing option of vSphere 6.0.
- How much Maximum RAM can support vSphere 6.0?
It supports upto 12TB of RAM.
Content Libraries
- What is Content Library?
Content Library is the central location point between two different geo-graphical locations with vCenter Servers where you can store VM templates, ISO images, scripts etc. and share them between geo-graphical locations
- What are main benefits of content libraries?
We create VM templates and can share on another geo-graphical location of a company without creating again on other locations. It has many benefits such as sharing and consistency, storage efficiency, and secure subscription.
- How many types Content Libraries have?
It has three types:
- Local: library of local control.
- Published: local library which contents (VM templates, ISO images etc) for subscription.
- Subscribed: A library which syncs with the published library
- What are requirements and limitations of Content Libraries?
A content library has following requirements and limitations
- Single storage which can size upto 64TB
- Maximum 256 items per library
- Sync occurs once every 24 hours
- What is VMFS?
VMFS is a file system for a VM in VMware vSphere. VMFS is a datastore that responsible for storing virtual machine files. VMFS can also store large files which size can up to 64TB in vSphere 6.0
VSAN
- What is vSAN?
Virtual SAN is a software defined storage first introduced in vSphere 5.5 and is fully integrated with vSphere. It aggregates locally attached storage of ESXi hosts which are part of cluster and creates distributed shared solution.
- What is cold migration?
To move a powered-off VM from one host to another is called cold migration.
- What is Storage vMotion?
To move a powered-on VM from one datastore to another is called Storage vMotion.
- What are different configuration options for VSAN?
There are two configuration options for vSAN:
- Hybrid: Uses both flash-based and magnetic disks for storage. Flash are used for cashing, while magnetic disks are used for capacity or storage.
- All-Flash: Uses flash for both caching and for storage
- Are there VSAN ready nodes are available in the market?
Yes, vSAN-ready such as VxRail 4.0 and 4.5 are available in the market. VxRail is the combination of min 3 servers which are part of a cluster and can scale up to 64 servers.
- How minimum servers/hosts are required to configure vSAN?
To configure a vSAN, you should have minimum 3 ESXi hosts/servers in the form of a vSAN cluster. If one of servers fails, vSAN cluster will fail.
- How many maximum ESXi hosts are allowed for vSAN?
64 hosts are max allowed to configure a vSAN cluster.
- How many disk groups and max magnetic disks are allowed in single disk group?
Maximum 5 disk groups are allowed on an ESXi host which is a part of vSAN cluster and maximum of 7 magnetic and 1 SSD per disk group is allowed.
- How many type of storages can we use in our virtual environment?
- Direct Attached Storage
- Fiber Channel (FC)
- iSCSI
- Network Attached Storage (NAS)
- What is NFS?
Network File System (NFS) is file sharing protocol that ESXi hosts use to communicate with a NAS device. NAS is a specialized storage device that connects to a network and can provide file access services to ESXi hosts.
- What is Raw Device Mapping (RDM)?
Raw Device Mapping (RDM) is a file stored in a VMFS volume that acts as a proxy for a raw physical device. RDM enables you to store virtual machine data directly on a LUN. RDM is recommended when a VM must interact with a real disk on the SAN.
- What is iSCSI storage?
An iSCSI SAN consists of an iSCSI storage system, which contains one or more storage processors. TCP/IP protocol is used to communicate between host and storage array. iSCSI initiator is configured with the ESXi host. iSCSI initiator can be a hardware based either dependent or independent and software based known as iSCSI software initiator.
- What is the format of iSCSI addressing?
It uses TCP/IP to configure.
- What are iSCSI naming conventions?
iSCSI names are formatted in two different ways:
- the iSCSI qualified name (IQN)
- extended unique identifier (EUI)
vApp
- What is vApp?
vApp is a container or group where more than one VMs can be package and 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 their power-on and power-off sequence.
- What settings can be configured for vApp?
We can configure several settings for vApp such as CPU and memory allocation, and IP allocation policy etc.
Miscellaneous
- What is VMware DRS?
DRS stands for Distributed Resource Scheduler; that automatically balances available resources among various hosts by using cluster or resource pools. With the help of HA, DRS can move VMs from one host to another to balance the available resources among VMs.
- What is share, limit, and reservation?
Share: A value that specifies the relative priority or importance of a VM access to given resource.
Limit: Consumption of a CPU cycle or host physical memory that cannot cross the defined value (limit).
Reservation: This value defines in the form of CPU or memory and must be available for a VM to start.
- What are alarms why we use them?
An alarm is a notification which appears when an event occurs. Many default alarms exist for many inventory objects. Alarms can be created and modified using vSphere Web Client;
- What are the hot pluggable devices which can be added while VM is running?
We can add HDDs and NIC while VM is running.
- What is a Template?
Whan a VM is converted into a format which can be used to create a VM with pre-defined settings is called a template. An installed VM can be converted into a template but it cannot be powered-on.
- What is Snapshot?
To create a copy of a VM with the time stamp as a restore point is called a snapshot. Snapshots are taken when an upgrade or software installation is required. For better performance, a snapshot should be removed after particular task is performed.
- How to convert a physical machine into a VM?
Three steps are required to convert 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
- What is vMotion and what is the main purpose to use it in virtual environment?
It is very prominent feature of VMware vSphere used to live migrate running VMs from one ESXi host to another without any downtime. Datastores and ESXi hosts both can be used while vMotion.
- What is difference between clone and template?
A clone is a copy of a virtual machine. By cloning a VM, it will save time if multiple VMs with same configurations are required to configure. 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.
- What monitoring method is used in vSphere HA?
- Network Hearbeat
- Datastore Heartbeat
- How master host is elected in vSphere HA?
When HA is enabled in a cluster, all hosts take part in selection process to be selected as a master host. A host which has highest number of datastores mounted, will be selected as a master host. All other hosts will remain slave hosts.
- What is the purpose of VMware Tools?
It is a suite of utilities which are used to enhance performance of a VM in the form of graphics, mouse/keyboard movement, network card and other peripheral devices.
- What is VMware DPM?
Stands for Distributed Power Management is a feature of VMware DRS is used to monitor required resources in a cluster. When the resources are decreases due to low usage, VMware DPM consolidates workloads and shut down the hosts which are not being used, and when resources are increased it automatically power on the un-used hosts.
- What is ESXi Shell?
It is a command-line interface is used to run repair and diagnostics of ESXi hosts. It can be accessed via DCUI, vCenter Server enable/disable, and via SSH.
- How to run ESXTOP on ESXi host?
To run ESXTOP on an ESXi host, we’ll need two pre-requisites:
- Install vSphere Client on a host where you want to configure
- Enable SSH from DCUI by using “Troubleshooting Options” link
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What is VMware HA?
As per VMware Definition,
VMware® High Availability (HA) provides easy to use, cost effective high availability for applications running in virtual machines. In the event of server failure, affected virtual machines are automatically restarted on other production servers with spare capacity
What is AAM in HA?
AAM is the Legato automated availability management. Prior to vSphere 4.1, VMware’s HA is actually re engineered to work with VM’s with the help of Legato’s Automated Availability Manager (AAM) software. VMware’s vCenteragent (vpxa) interfaces with the VMware HA agent which acts as an intermediary to the AAM software. From vSphere 5.0, it uses an agent called “FDM” (Fault Domain Manager).
What are pre-requites for HA to work?
1.Shared storage for the VMs running in HA cluster
2.Essentials plus, standard, Advanced, Enterprise and Enterprise Plus Licensing
3.Create VMHA enabled Cluster
4.Management network redundancy to avoid frequent isolation response in case of temporary network issues (preferred not a requirement)
What is maximum number of primary HA hosts in vSphere 4.1?
Maximum number of primary HA host is 5. VMware HA cluster chooses the first 5 hosts that joins the cluster as primary nodes and all others hosts are automatically selected as secondary nodes.
How to see the list of Primary nodes in HA cluster?
View the log file named “aam_config_util_listnodes.log” under /var/log/vmware/aam using the below command
cat /var/log/vmware/aam/aam_config_util_listnodes.log
What is the command to restart /Start/Stop HA agent in the ESX host?
service vmware–aam restart
service vmware–aam stop
service vmware–aam start
Where to located HA related logs in case of troubleshooting?
/Var/log/vmware/aam
What the basic troubleshooting steps in case of HA agent install failed on hosts in HA cluster?
1. Check for some network issues
2. Check the DNS is configured properly
3. Check the vmware HA agent status in ESX host by using below commands
service vmware–aam status
4. Check the networks are properly configured and named exactly as other hosts in the cluster. otherwise, you will get the below errors while installing or reconfiguring HA agent.
5. Check HA related ports are open in firewall to allow for the communication
Incoming port: TCP/UDP 8042-8045
Outgoing port: TCP/UDP 2050-2250
6. First try to restart /stop/start the vmware HA agent on the affected host using the below commands. In addition u can also try to restart vpxa and management agent in the Host.
service vmware–aam restart
service vmware–aam stop
service vmware–aam start
7. Right Click the affected host and click on “Reconfigure for VMWare HA” to re-install the HA agent that particular host.
8. Remove the affected host from the cluster. Removing ESX host from the cluster will not be allowed untill that host is put into maintenance mode.
9.Alternative solution for 3 step is, Goto cluster settings and uncheck the vmware HA in to turnoff the HA in that cluster and re-enable the vmware HA to get the agent installed.
10. For further troubleshooting , review the HA logs under /Var/log/vmware/aam directory.
What is the maximum number of hosts per HA cluster?
Maximum number of hosts in the HA cluster is 32
What is Host Isolation?
VMware HA has a mechanism to detect a host is isolated from rest of hosts in the cluster. When the ESX host loses its ability to exchange heartbeat via management network between the other hosts in the HA cluster, that ESX host will be considered as a Isolated.
How Host Isolation is detected?
In HA cluster, ESX hosts uses heartbeats to communicate among other hosts in the cluster.By default, Heartbeat will be sent every 1 second.
If a ESX host in the cluster didn’t received heartbeat for for 13 seconds from any other hosts in the cluster, The host considered it as isolated and host will ping the configured isolation address(default gateway by default). If the ping fails, VMware HA will execute the Host isolation response
What are the different types isolation response available in HA?
Power off – All the VMs are powered off , when the HA detects that the network isolation occurs
Shut down – All VMs running on that host are shut down with the help of VMware Tools, when the HA detects that the network isolation occurs
.If the shutdown via
VMWare tools not happened within 5 minutes, VM’s power
offoperation will be executed. This behavior can be changed with the help of HA advanced options. Please refer my Post on
HA Advanced configuration
Leave powered on – The VM’s state remain powered on or remain unchanged, when the HA detects that the network isolation occurs.
How to add additional isolation address for redundancy?
By default, VMWare HA use to ping default gateway as the isolation address if it stops receiving heartbeat.We can add an additional values in case if we are using redundant service console both belongs to different subnet.Let’s say we can add the default gateway of SC1 as first value and gateway of SC2 as the additional one using the below value
1. Right Click your HA cluster
2. Goto to advanced options of HA
3. Add the line “das.isolationaddress1 = 192.168.0.1″
4. Add the line “das.isolationaddress2 = 192.168.1.1″ as the additional isolation address
What is HA Admission control?
As per “VMware Availability Guide”,
VCenter Server uses admission control to ensure that sufficient resources are available in a cluster to provide failover protection and to ensure that virtual machine resource reservations are respected.
What are the 2 types of settings available for admission control?
Enable: Do not power on VMs that violate availability constraints
Disable: Power on VMs that violate availability constraints
What are the different types of Admission control policy available with VMware HA?
There are 3 different types of Admission control policy available.
Host failures cluster tolerates
Percentage of cluster resources reserved as fail over spare capacity
Specify a fail over host
How the Host Failures cluster tolerates admission control policy works?
Select the maximum number of host failures that you can afford for or to guarantee fail over. Prior vSphere 4.1, Minimum is 1 and the maximum is 4.
In the Host Failures cluster tolerates admission control policy , we can define the specific number of hosts that can fail in the cluster and also it ensures that the sufficient resources remain to fail over all the virtual machines from that failed hosts to the other hosts in cluster. VMware High Availability(HA) uses a mechanism called slots to calculate both the available and required resources in the cluster for a failing over virtual machines from a failed host to other hosts in the cluster.
What is SLOT?
As per VMWare’s Definition,
“A slot is a logical representation of the memory and CPU resources that satisfy the requirements for any powered-on virtual machine in the cluster.”
If you have configured reservations at VM level, It influence the HA slot calculation. Highest memory reservation and highest CPU reservation of the VM in your cluster determines the slot size for the cluster.
How the HA Slots are Calculated?
How to Check the HA Slot information from vSphere Client?
Click on Cluster Summary Tab and Click on “Advanced Runtime Info” to see the the detailed HA slots information.
What is use of Host Monitoring status in HA cluster?
Let’s take an example, you are performing network maintenance activity on your switches which connects your one of th ESX host in HA cluster.
what will happen if the switch connected to the ESX host in HA cluster is down?
It will not receive heartbeat and also ping to the isolation address also failed. so, host will think itself as isolated and HA will initiate the reboot of virtual machines on the host to other hosts in the cluster. Why do you need this unwanted situation while performing scheduled maintenance window.
To avoid the above situation when performing scheduled activity which may cause ESX host to isolate, remove the check box in ” Enable Host Monitoring” until you are done with the network maintenance activity.
How to Manually define the HA Slot size?
By default, HA slot size is determined by the Virtual machine Highest CPU and memory reservation. If no reservation is specified at the VM level, default slot size of 256 MHZ for CPU and 0 MB + memory overhead for RAM will be taken as slot size. We can control the HA slot size manually by using the following values.
There are 4 options we can configure at HA advanced options related to slot size
das.slotMemInMB – Maximum Bound value for HA memory slot size
das.slotCpuInMHz – Maximum Bound value for HA CPU slot Size
das.vmMemoryMinMB – Minimum Bound value for HA memory slot size
das.vmCpuMinMHz – Minimum Bound value for HA CPU slot size
For More HA related Advanced options, Please refer my
blog post
How the “Percentage of cluster resources reserved as failover spare capacity” admission control policy works?
In the Percentage of cluster resources reserved as failover spare capacity admission control policy, We can define the specific percentage of total cluster resources are reserved for failover.In contrast to the “Host Failures cluster tolerates admission control policy”, It will not use slots. Instead This policy calculates the in the way below
1.It calculates the Total resource requirement for all Powered-on Virtual Machines in the cluster and also calculates the total resource available in host for virtual machines.
2.It calculates the current CPU and Memory Failover capacity for the capacity.
3.If the current CPU and Memory Failover capacity for the cluster < configured failover capacity (ex 25 %)
4.Admission control will not allow to power on the virtual machine which violates the availability constraints.
How the “Specify a failover host” admission control policy works?
In the Specify a failover host” admission control policy, We can define a specific host as a dedicated failover host. When isolation response is detected, HA attempts to restart the virtual machines on the specified failover host.In this Approach, dedicated failover hist will be sitting idle without actively involving or not participating in DRS load balancing.DRS will not migrate or power on placement of virtual machines on the defined failover host.
What is VM Monitoring status?
HA will usually monitors ESX hosts and reboot the virtual machine in the failed hosts in the other host in the cluster in case of host isolation but i need the HA to monitors for Virtual machine failures also. here the feature called VM monitoring status as part of HA settings.VM monitoring restarts the virtual machine if the vmware tools heartbeat didn’t received with the specified time using Monitoring sensitivity.
Clone
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Template
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Clone creates an exact copy of a running Virtual Machine at the time of cloning process
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Template acts as a baseline image with the predefined configuration as per organization standards
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Cloning a virtual machine creates a exact duplicate copy of the virtual machine with the same configuration and installed software without performing any additional settings.
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Create a template to create a master image of a
virtual machine from which you can deploy multiple virtual machines
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You can create a clone of existing installed and Configured running virtual machine by right clicking the VM and Clone.
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You can create a template by converting a virtual machine
to a template, cloning a virtual machine to a template, or cloning another template
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VM clones are best suited in test and development environments where you want to create, test and work with exact copies of production servers without disturbing production servers by creating clone of the production virtual machine.
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Templates are best suited for production environments where you want the mass deployment of virtual machines along with the installed OS and basic software, configured policy as per the security policy of your organization as a base Machine. Once template is deployed, you can install software depend on the role of the server like IIS,Database
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VM Clones are not suited for mass deployment of Virtual Machines
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Templates are best suited for Mass Deployment of Virtual
Machines
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We Cannot Convert back the Cloned Machine
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You can convert the template back to virtual machine to update the base template with the latest released patches and updates and to install or upgrade any software and again convert back to template to be used for deployment of virtual machines with latest patches.
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Cloned Virtual Machine Can be powered on
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Templates cannot be powered on
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You cannot Clone a Virtual Machine if you have connected directly to ESX/ESXi host using vSphere Client
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You cannot create a template of a Virtual Machine if you have connected directly
to ESX/ESXi host using vSphere Client
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You can customize the guest operating system of the clone to change the virtual machine name, network settings, and other properties. This prevents conflicts that can occur if a virtual machine and a clone with identical guest operating system settings are deployed simultaneously.
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You can also Customize the guest operating system while deploying from template
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Clone of a virtual machine can be created when the virtual machine is powered on
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Convert virtual Machine to template cannot be performed, when Virtual machine is powered on. Only Clone to Template can be performed when VM is powered on
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