VCA HA why do we use it over simpler HA/FT for VCA?

[zeebahi]

Hi everyone,

VCA  HA requires Witness VM, Cloned passive VM to be created to provide VCA redundancy.

But we can provide the same functionality using simple HA for VM hosting VCA. For example, we can define the criteria if VM/host hosting VCA , if VCA VM is not reachable, start  cloned VCA's VM on a different host.

Better yet, we can use Fault tolerance feature for VCA's VM.

In both these cases, only one VM will activated if VCA is down.

Keeping in view the above two features why does one want to use VCA HA that requires more resources such as Witness node , Clone Passive VM for VCA?

Thanks and have a good weekend!!

[NathanosBlightc · Accepted solution]

Respect to the availability factor, I believe you must compare the new feature of VCHA with the FT feature, because by the vCenter HA you want to provide a specific-cluster for vCenter itself to create a situation with zero downtime, as same as FT will do it. BTW after many improvements of FT in vSphere 6.7, FT still have some limitations like 8 vCPU or thin VDMK. So you may need for example more than 8 vCPU for your vCenter server. So in this case you need to use VCHA for very high-critical (highest-level of availability) vCenter Server