Just trying to get some ideas. We are having issues with upgrading our vCenter from 5.5 to 6.5u1. Support suggested to build a new vCenter appliance and bring in the existing ESXi hosts.
So can I build a new vCenter appliance 6.5u1 and then bring existing ESXi hosts version 5.5 (we have 5 hosts, 150 VMs) without downtime? Of course I would have to dis-joined each ESXi host from the current vCenter. Would this cause any downtime to the VMs? We have a shared storage for the VMs.
1) Build new vCenter (called vCenter2) on one of the existing ESXi hosts (for example host1)
2) Dis-join host1 from the current vCenter (called vCenter1).
3) Join host1 to new vCenter (vCenter2)
4) Do all the same for all the rest of the hosts
5) set HA, DRS, etc
6) set EVC
7) Vmotion the VMs off one host (host1), then upgrade host1 to 6.5
😎 Repeat step 7 for hosts 2-5
Note: We are about 10 months away from getting new hardware for this production cluster. So its it even worth it to do all of this (yes we are aware of 5.5 being out of support soon)?