We're currently on vSphere 6 Update 3 and I'm looking into upgrading to the latest vSphere 6.5d. The reason is that we're getting new hosts and a new SAN (3PAR), so it would be nice to start with the latest version.
We have Veeam Availability Suite and is running version 9.5 update 1. Does that support vSphere 6.5d? Should we update to Veeam Backup 9.5 update 2 before upgrading vCenter?
And if there's any gotchas and tips for the vCenter upgrade, then I'm all ears
René, please note that upgrade from vSphere 6.0 Update 3 to vSphere 6.5 is currently not supported by VMware, because 6.0 U3 was released after 6.5. I suspect we'll have to wait for 6.5 Update 1 before we can upgrade in-place.
You could certainly spin up a new vCenter 6.5 for your new environment, and then move your 6.0 U3 hosts into it. But then you'd have to deal with various issues and consequences of migrating to new vCenter. It might be less work to stay at 6.0 U3 for now, and upgrade to 6.5 U1 later.