Cisco has recently updated its hardware and software interoperability matrix for UCS B series blade servers. Last month they listed the B200 M2 and B230 M2 blade servers as supported for vsphere 6 but not the B250 M2s under UCS version 2.1(3) which we currently have running.
Just last week the interoperability matrix under UCS version 2.2(3) listed the B200 M2s and B230 M2s but again not the B250 M2s as compatible with vsphere 6.
We are not at the moment planning on a upgrade from vsphere 5 to 6 but its possible we will in the next several months. I am in the immediate need to add memory capacity to my hosts which are currently dell R710s. We have several B200 M2, B230 M2, and B250 M2 UCS servers. The memory we have installed in the B250 M2s would solve the memory constraints we currently have.
If I were to solve my memory issues by moving my hosts to the B250 M2s now under vsphere 5.0. Should I be worried that I will not be able to then upgrade the hosts to vsphere 6.0 in the future? The dell R710s are already listed as supported in vpshere 6.0.
It seems the HCL from many companies are a work in progress. However they have updated it a few times and support for the B250 seem elusive. If you have a server to spare, why not do a test install on ESXi 6.0 now before you install 5.5 on it and find out down the road you're screwed when you want to upgrade.
Just an idea if you can spare the resource
The best thing to do before you spend any $$$ upgrading your hosts is to always check with the VMware HCL as it is constantly getting updated by contributions from partner Vendors. It is also a good idea to check with the Vendor as to what is supported or isn't by your particular hardware. They will be able to point you in the right direction before spending money.
Installed vSphere 6 on a B250 M2 today with no issues. Used the stock ESXi 6 .ISO for the install. I am running UCSM 2.2(3b) with FW 2.1 for Blades. Its been a while but I think I found that M2 series seem to work better with Blade FW 2.1 than the newer FW versions and that is why its using 2.1.
Was going to do an upgrade from 5.5 but ran into a conflicting VIBs issue for the Broadcom VIB. This is a well documented issue with other versions of ESXi. Since I ran into this I decided to just to an over-write install instead of the upgrade. In my case it wasn't important to do the upgrade path.