Best Practice for MSA1500cs with two MSA30s

[Jason Geuder]

Hello,

I have an MSA1500cs with two MSA30 enclosures. I have found a great deal of information on how to make the FC fabric highly available but very little information on how to protect the SAN if I would lose a MSA30.

Could somebody please provide me with advice on how to setup the RAID configurations and drive placement to protect the SAN if one the MSA30s would go down? Or are they reliable enough that I should not worry too much about it?

Thanks!

-Jason

[Steven Clementi]

Jason:

Honestly, there is not very much you can do with only 2 shelves, without losing usable storage.

1st... the shelf itself is 3rd and maybe even 4th generation. It is a pretty solid design and generally does not fail. Usually, the problem is more of an environmental issue like the loss of power. Make sure the 2 power supplies are definitelly on 2 totally separate circuits, 2 separate UPS's and even 2 separate sources of power, if at all possible.

2nd... keep your arrays small. Though you may eat up some extra space if using RAID 5, RAID 1+0 should offer about the same amount of usable space whether or not you have 14 arrays of 2 disks each, vs. 7 arrays of 4 disks each vs. 4 arrays of 7 disks each. Use the OS or some 3rd party utility to "span" drives or otherwise combine volumes to create larger virtual disks.

3rd... getting a third and/or 4th MSA30 (if possible) would decrease your usable space loss if you had to use RAID5 or RAID ADG for anything. You can safely group up to 6 or 8 disks in one array and use RAID ADG and be safe from a disk shelf failing.

Hope this at least kicks you into gear...


Steven