We have 4 hosts running esxi 5.5u3 connected to a shared SAN and a vcenter appliance vm. All hosts are Dell R710 servers with E5620 processors (Westmere generation). We're taking the plunge and adding an R730 server with an E5-2660v3 (Haswell) and hoping to avoid having to down all the guests to enable EVC. From what I've read, it looks like I could enable our current cluster with the Westmere baseline when I'm ready, then add the new server into that cluster. No downtime, no muss, no fuss. Is that correct?
I realize that limits us to features on the older processor so we won't be able to take advantage of the Haswell features, but we're more interested in continuity right now. In the summer, we'll be able to add more R730s, at which time I would move all VMs off of the older hosts and raise the EVC baseline to Haswell.
Please, someone let me know if this plan sounds correct, or if I've been getting into the catnip too much.
Thanks.