Basic Question about C-Series disks

[mdrudge]

I am trying to spec out a C-series rackmount with local storage.  I would like to have a large RAID-6 volume with 8 drives, but I would also like a smaller Raid-1 mirrored disk with 2 drives for the C: drive of the server.  When looking at specs, it appears I can only have one RAID controller.  This seems like a pretty basic config to me, but the configuration tool barfs if I try to use two different types of drives.  Does UCS not support this kind of configuration?  What am I missing here?  Bear with me since I am used to dealing with FC and storage arrays, not local storage.  Do I need to just configure a group of identical drives as two RAID-6 volumes?  Thanks!

[Wes Austin]

You typically will require the same drive type (SSD vs HDD) and similar capabilities in order to form a RAID between disks. If you can share the drive types you are using or what the error message you are getting is, we might be able to provide more insight, but seems your understanding is correct. 

[Steven Tardy · Accepted solution]

Sounds like you are fighting the out-of-the-box configuration/ordering tool. Wouldn't doubt if the configuration tool has some limitations like you are seeing.

The spec sheet says 64 RAID groups can be configured:
https://www.cisco.com/c/dam/en/us/products/collateral/servers-unified-computing/ucs-c-series-rack-servers/c220m6-sff-specsheet.pdf

NOTE: 64 RAID groups (virtual drives) are supported with this RAID controller.

The internal M.2 disks are great as a boot device leaving all external disks for mass storage.
This requires a controller (UCS-M2-HWRAID) and 2x M.2 disks (ex: UCS-M2-240GB).

[mdrudge]

Thanks for the replies!  Yes, I was struggling with the tool.  I thought that the tool might stop me from trying a configuration that wasn't possible.  Unfortunately, I'm going to have to use SED drives, so I don't think I can use M.2 disks.  This does clarify my understanding.  Thanks, again!