HA is High Availability service provided by VMWare, where resources are grouped in to a cluster, in case of any breakdowns of ESXi’s automatically, cluster triggeres and the VM’s will be migrated to another ESXi to resume the availability of resources. This helps in providing customers a continuous application services.

In this lab, we create a cluster and move our ESXi resources to it. Then We shutdown Master ESXi and verify how the post process works in HA. A dedicated switch is required for HA service .

Later, we change the resources reservation and check the effects on other hosts.

Task1:Create a cluster Enabled Vsphere HA

Step1:Select Dataceneter in Hosts and clusters and click New cluster

Step2: Check Vsphere HA ON and name as Lab Cluster

Step3: Verify in the status bar for cluster is created

Task2:Add your ESXi Host to cluster

Step1:Drag both ESXi’s to cluster

Step2: Click on LabCluster >Monitor tab>Vsphere HA to view the master client – 172.20.10.51

Step3:View heartbeat through which datastores checks are configured

Step4: navigate to Monitor> issues tab where issues are listed

Step5:Navigate to VMKernel Adapters and click on Vmotion adapter

Step6: Check Management service to enable it

Step7: repeat the same to ESXi2

Task3: Test vSphere HA Fuctionality

Step1: Click on ESXi and select reconfigure for vsphere HA on both the ESXi’s

Step2: verify that both the issues are resolved

Step3:Makesure one virtual machine is turned on On Master client

Step4: reboot the master client

Step5: Give reason as Testing Vsphere HA

Step6: The master client changes from 172.20.10.51 to 172.20.10.52

Since my VCSA is on ESXI1 (Master) so we are rebooting ESXi2

Step7: Different Events are triggered which can be monitored in Tasks and Events tab

Step8:All the VM’s are moved from ESXi2 to ESXI1 (Navigate to ESXI and VM’s tab)

Task4: View the Vsphere HA CLuster Resource Usage

Step1: Navigate to Hosts and clusters>Select Lab cluster>Monitor>Resource reservation to check cluster capacity

Step2: Select VM’s tab and check the reservations of VM’s will be set to 0MHz

Task5: Manage Vsphere HA SlotSize

Step1:Move to Configure tab and select vsphere availability and click edit

Step2: Select Admission control and change Define failovercapacity to SLot Policy and OK

Step3: Navigate to VsphereHA Summary to check the Slot Size and Total Slots in cluster

Step4:Select VM2-2 >EditSettings

Step5: expand CPu and increase reservation to 512Mhz

Step6:Navigate back to Vsphere HA and check Advance runtime info which increased from 32 to 512 since the reservation is set

Step7: LabCluster>Settings

Step8: Admission Control> Select Fixed Slot Size

Step9: Change CPU SLotSize to 300 and memory slot to 82 and click calculate which gives 1/3 slots required…which means the 512HZ CPu will use 3 CPU’s to power on

Step10: View the updated Memory and CPu in Vsphere HA Tab

Step11: Remove the HA Fixed slot Setting LabCluster>Settings>vsphere Availability>Edit>Admission Control> Define Host failover Capacity by>Cover all Powered on Virtual machines

Step12:Remove the reservation by expanding VM> expand CPU and Reservation to 0

Task6: Configure a Vsphere HA with administrative control

Step1: Turn off VM2-3 and all virtual machines

Step2: Navigate to Monitor>Resource reservation>Memory, the available reservation is less than total

Step3:Assign 300 MB reservation for VM2-1 by expanding Memory option of VM

Step4:Navigate to VsphereHA tab>Summary in monitor

Step5: Navigate to VM2-1 and power on and check monitor tab the memory utilization goes down to 27(Half of assigned)

Step6: Right click VM1-2 and start the VM , It will through an error stating resources are insufficient

Task7:Prepare for Next lab

Step1: Remove the reservation from VM2-1

Step2: Edit cluster settings>Admission Control>Failover capacity to disabled

Trouble shooting: The lab was complex but straightforward, which can be attained but pre-requisistes like switches should be of same name, Network of hosts in different ESXi’s should be in sync and HA service enabled VM Kernel adapter should be used are must.

Critical thinking: This lab is little annoying since, many objectives were discussed, HA triggering was simple and concise but Cluster management has lot of options and admission controls resource monitoring were also included in this part of lab making it difficult and hectic.

However, in Business High availability is must to provide better and continuous customer service, even though the VMWare HA is not instant (The resources take time to migrate and poweron in other ESXI service) it is easy to configure and time depends on VM hardware size. So,based on VM Size the architecture should be maintained,grouped and configured to avoid delayed services.