HPE EVA Storage

MSA 1000: Can I use just 1 array?

 
CCarranza
Occasional Contributor

MSA 1000: Can I use just 1 array?

Hi all,

We're planning some expansion on an MSA1000. My boss says that we need to have two separate arrays on the new enclosure, one for Bays 1-7, the other for Bays 8-14. Is there any reason that we need to do this?

My plan was to have the entire MSA30 shelf be 1 array, then create RAID 6 logical drives from that. I don't understand what splitting drives into separate arrays gain us.

Thanks,
CC
3 REPLIES 3
Víctor Cespón
Honored Contributor

Re: MSA 1000: Can I use just 1 array?

You mean these two options?

A) 2 RAID 5 of 7 disk each
B) 1 RAID 6 of 14 disks

Then RAID 6 is more secure, taking the values from this chart:

http://docs.hp.com/en/J6369-90050/apas01.html

The read performance would be greater on the RAID 6 (more spindles). For the write performance I'm not sure, RAID 6 is slower, but you'll have twice the number of disks.
CCarranza
Occasional Contributor

Re: MSA 1000: Can I use just 1 array?

My two options are:

1.) Array A and Array B, each with 7 drives.

OR

2.) Array A with 14 drives.

Either way, I plan on RAID 6 logical drives. I just don't understand what advantage 2 arrays get me.
Víctor Cespón
Honored Contributor

Re: MSA 1000: Can I use just 1 array?

RAID 6 with only 7 disks is overkill. Of course two independent arrays with RAID 6 LUNs give you more security. You'll have to lose 3 drives out of 7 at the same time.

This is very unlikely to happen. Even with 14 disks, a RAID 6 is secure enough. The probablity of 3 disks faling the same day is soooooo low...