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nal heartbeat to check the VM all the time. If the VM is stopped functioning, VM will be restarted automatically by vSphere HA.12.What is the use of vMotion ?

Using vMotion feature,we can move the running VM s from one ESXi host to another ESXi host without any downtime. vMotion copies the VM s in-memory contents to the destination server and freeze the operation on current ESXi host and resumes theVM s on remote ESXI node. VMware vMotion13.What is the use of Storage vMotion ?

vMotion is possible only when you have Shared storage like FC-SAN,ISCSI-SAN or NFS. If you want to move the VM from one datastore to another datastore without any downtime,then you need to perform storage vMotion. vMotion and Storage vMotionNote: You can perform the vMotion and Storage vMotion together without any downtime.14.Why vMotion feature is not used/can t use in vSphere HA ?

vMotion is used for planned migrations and possible only where the source and de

stination ESXI hosts are running properly.vSPhere HA is used to reduce the downtime due to failures of physical ESXi hosts.So When the failure accours on ESXi nodes, there is no time to perform vMotion and can t be used.15.Is there any way to prevent the VM s unplanned downtime using vSphere HA ?

Yes.You can prevent the unplanned downtime using vSphere falut tollerance alongwith vSphere HA.16.How the vSphere Fault tolerance(FT) works ?

Using vLockstep technology , vSphere FT maintains the mirrored secondary VM on different ESXi physical host that is kept in lockstep with the primary.So when the primary ESXi node goes down due to hardware issue, secondary VM will immediately step-in and provide the service. At this point, this VM will become primary and secondary aka mirrored VM will be created on possible ESXI host to prevent the further ESXi failure.

VMware Fault Tolerance (FT)17.What is vSphere DRS(Distributed Resource Scheduler) ? How it works ?

vSphere DRS is an intelligent frame works which always monitors the cluster nodes health check and performs the vMotion automatically whenever required. For anexample ,if one of the ESXI cluster host memory has been utilized more than 90%and due to that lot of paging happening on that server. vSphere DRS detects such things in quick time and moves few VM s to another ESXi cluster to least-balancethe cluster nodes without any downtime by leveraging vMotion functionality. It applies for high contention for CPU utilization too. So vSphere DRS helps to balance the CPU & Memory utilization across the ESXi cluster nodes.

Vmware DRS

18. What is vSphere storage DRS ? How it works ?vSphere Storage DRS like vSphere DRS but it applies to storage.It helps to balance storage utilization and performance between data-stores on same ESXi clusters. `19.What is VSAN ? How it works ?

VSAN forms the storage pools across the multiple nodes using internal disks andallows you to create a datastores that spans multiple ESXI hosts. VSAN also protect the data using VM storage profiles and you can configure it according to your requirement. You need SSD s(Solid State Drive) to configure VSAN. Click here to


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learn more about VSAN. VSAN overview20.What is Flash Read Cache ?

vSphere 5.5 supports solid state drive through feature called Flash Read Cache.Using Flash Read Cache, you can assign a caching space to VM s like how are you assigning like CPU,Memory and other resources to VM s. Solid state drive can providemuch better that IOPS compare to normal disks. Flash Read Cache21.What is the use of Storage I/O Control in vSphere 5.5 ?

You can limit the number of IOPS for each VM.22.What is the use of network I/O control ?

Its similar to storage I/O control but its controls the VM s Network bandwidth.23.What is vSphere Replication?

It replicates the complete VM from one datacenter to another datacenter on per VM basis Unlike hardware replication. vSphere ReplicationHope I have mostly covered about all the vSphere products and it features in high level.Share it ! Comment it !! Be Sociable!!!

How to calculate the vSphere s VM memory usage ?July 30, 2014 in VMware vSphereTo understand, VMware s memory management required some sort of skills. Because it had bounded with many technologies like sharing the memory between virtual machines(TPS) , compressing the memory content, Eliminating the duplicate memory content etc As a Unix/Linux/Windows admin , we can login to guest VM and check the current memory usage at the VM level. But to understand, how the VM is getting the physical memory at the ESXi level , You have to login in to vSphere Client and check the Resource Allocation tab.Most the members get confused after seeing the VM s resource allocation tab from vSphere Client. This article is going t0 explain how VMware is calculating the virtual memory and how to find the VM s real memory usage.Memory Usage from VM guest Level

Login to the guest OS and see how much memory in use .VM- Redhat Linux# toptop - 10:45:26 up 243 days, 22:01, 1 user, load average: 0.02, 0.02, 0.00Tasks: 143 total, 1 running, 142 sleeping, 0 stopped, 0 zombieCpu(s): 0.1%us, 0.0%sy, 0.0%ni, 99.8%id, 0.0%wa, 0.0%hi, 0.0%si, 0.0%stMem: 5858188k total, 5792276k used, 65912k free, 245984k buffersSwap: 2064376k total, 96k used, 2064280k free, 4968504k cached# free -m total used free shared buffers cachedMem: 5720 5656 64 0 240 4852-/+ buffers/cache: 564 5156Swap: 2015 0 2015#

According to the VM, physical memory is used 5656MB. (5.5GB~)Memory usage from vSphere Client s Resource allocation tabLogin to vSphere Client and Select host and clusters . Just find the VM and select the Resource allocation table. VMware vSphere Client VM Memory usageAfter looking the Resource allocation tab, confusion begins about the VMware memory management.We will see the memory terms in VMware vSphere and how it works ?

What is Guest Memory ? Amount of Memory that you have allocated to the VM.


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