I have a cluster of three nodes with HPE servers gen 9 with Intel(R) Xeon(R) CPU E5-2620 v4 @ 2.10GHz processors, I have another empty server HPE gen 9 with Intel(R) Xeon(R) CPU E5-2620 v3 @ 2.40GHz
It's possible to enable EVC in the cluster that i have without any downtime.
VMware ESXI 6.5
VMware vCenter 6.5
If you are going to go to a level of EVC that is lower than the baseline that your vms are running, there is no other way of shutting down the VMs, then enable EVC and power on again.
A possible workaround if you cant shutdown everything at the same time, you can set the level of "EVC" at a vm level, so you can do a the change in stages then enable EVC at a cluster level!
https://www.altaro.com/vmware/per-vm-evc/
Anything started at the higher level, has to be shutdown, regardless of per VM evc or the cluster level evc. Per evc is nice where you can just do restarted ones temporarily.
If you are going to go to a level of EVC that is lower than the baseline that your vms are running, there is no other way of shutting down the VMs, then enable EVC and power on again.
A possible workaround if you cant shutdown everything at the same time, you can set the level of "EVC" at a vm level, so you can do a the change in stages then enable EVC at a cluster level!
https://www.altaro.com/vmware/per-vm-evc/
Anything started at the higher level, has to be shutdown, regardless of per VM evc or the cluster level evc. Per evc is nice where you can just do restarted ones temporarily.