Creating a cluster with mixed full / half height HP blade servers

[yliu9]

Hi All,

I'm hoping there's someone out there who's got a mixture of full height and half height blades in their VMware clusters.

We've currently got a c7000 blade chassis populated with a couple full height blades forming 2 separate clusters. As a "DR" (I refrain from using this unless if its "true" DR) we're going to stick in another c7000 and will have blade servers in there too.

Due to some... design reasons, it has been identified we perhaps should have gone with half heights to start with anyway. So I'm after some "gotchas" with clustering a mix of full & half height blades.

My understanding is that so long as networks are identically setup, storage identically presented, and there are no mismatch between CPUs (shouldn't be a problem now that there's a switch to dumb things down), we shouldn't have a problem.

If you got any ideas or feedback around this I'd love to hear them.

[Troy_Clavell]

the most important thing will be CPU compatibility for vmotion and DRS. If you have that you shouldn't run into any problems. Also, adding them do the same enclosure really makes not difference at all for ESX Clustering. Worse case you create a new vCenter cluster and add the new blades to the new cluster. Or create an EVC cluster and move everything to it. In my opinion 8 seems to be a good number for a DRS/HA Cluster. If more than that, I would create a new HA/DRS cluster.

Good Luck!

[yliu9]

Troy, thanks for the pointers.

CPU compatibility shouldn't create much of a headache due to the EVC mode (and the CPU models are so close that there are virtually no performance difference).

These half heights are actually going into a different enclosure, which will be located at a different site altogether. SAN storage will be presented via fibre across the sites.

I think I've ticked off most of the boxes, just hoping there's not going to be anything that will bite me once the kit's being built and someone screams "its not working!"