Mix Intel and AMD hosts in HA cluster

Essendon

We were having this discussion at work about mixing hosts with different chipsets in a HA cluster (not EVC cluster). While I haven't tried this myself, but I reckon you can add them to a cluster. Whether or not VM's will be able to vMotion around is the other thing. So,

- Will Windows BSOD when it realizes it's on different CPU architecture?
- Does the cluster complain when you add a host with different architecture?

Now I know you shouldn't do this in production, but we may have an SMB client who is looking at shrinking from 3 sites to 2 sites. They dont want to spend any more money than necessary and reuse existing hardware. Both AMD and Intel hosts are fairly new. Because of the way there things are setup they cannot have all the Intel's at one site and the AMD's at the other site. I was thinking -

- Split workloads into separate Intel and AMD clusters
- Enable EVC, there could be a need for FT sometime soon. There's an application server that does some billing application.

What do you guys think/suggest?

dave330i

EVC doesn't work across Intel & AMD. HA is a restart, so that should work between Intel & AMD. vMotion won't work. Cold migration will work. Best to make an Intel cluster and AMD cluster.

Essendon

Exactly the kind of answer I was after!

tstrip007

Not sure about the BSOD but I noticed the other day that I had to relicense a windows vm when I cold migrated from one intel host to another with a diff gen intel CPU.

Essendon

Cheers for the comment @tstrip, there must be some kind of licensing agreement in place. I now remember having a similar issue a while ago, thanks for the reminder.

kj0

You could always do it as a "Test".

Ecio

Dave330i is right, according to VMware KB: VMware KB: EVC and CPU Compatibility FAQ

Does EVC allow AMD and Intel CPUs to be vMotion compatible?
No. An EVC-enabled cluster only allows CPUs from a single vendor in the cluster. VirtualCenter and vCenter Server do not allow you to add a host from a different vendor into an EVC-enabled cluster.

jibbajabba

As for BSOD - Don't think so as the CPUs will likely be on the HAL ... Would be an issue if you'd need a driver when installing the OS on any AMD / Intel architecture ... like you do on funny storage controllers.So in a HA event you likely just see the first boot up taking a bit longer as it needs to install the drivers. To avoid that you could always just poweroff / move the VMs between the hosts, making sure when you go live that you got all drivers in the OS, Intel and AMD

sratakhin

AFAIK, the CPUs must be very similar for vMotion to work. We have servers with Xeon X56** and E54** and I can only migrate powered-off machines.

dave330i

sratakhin wrote: »

AFAIK, the CPUs must be very similar for vMotion to work. We have servers with Xeon X56** and E54** and I can only migrate powered-off machines.

Enable EVC. EVC should always be enabled. Even if the CPUs are identical.

Essendon

Yep, EVC should always be on.