Volume Network RAID Best Practices Question

[danblee]

Hi There,

I'm responsible for managing a P4500 and we've got two shelves of roughly 14TB in space. The disks are in their own physical RAID, but each volume that has been created also has a Network RAID of of RAID-10 (2-Way Mirror). This takes up an incredible amount of space, literally double what the volume would take up without RAID configured at the network data protection level.

So this means with 14TB of raw across two shelves we get 6.5TB of usable and then only 3.25TB available to our server. That's nuts! 

What has been your experience and best practice when working with network RAID at the volume level? Do you enable it or do you trust the RAID at the disk level?

Thanks in advance!

[BenLoveday]

Hi there,

It comes down to what you are expecting out of the SAN.

The NRAID is designed to give you data resiliency across multiple storage nodes and is really the whole point of Storevirtual, otherwise a small MSA would have done the job. In your current configuration it sounds like you could lose one whole node plus multiple drives in the remaining node without data-loss. Can I assume that your nodes are using RAID10 locally?

If you have fairly light workloads that are mostly sequential then you could probably get away with RAID5/6 at the local node level to give you more usable node capacity.

To be honest you might want to start thinking of refreshing the hardware as these are well out of support now.

Cheers,

Ben