Upgrading from 2x1TB mirror to 4x1TB

[Magnetz]

I have a dell T20 (12GB ram) with 2x1TB drives in a mirror with encryption that I use to store my backups, I don't have AES-NI so CPU is the bottleneck but performance is generally OK.

How should I add my 2 new 1tb drives? Another mirror in the same pool? Another mirror in a different pool, or go raidz2?

I don't want to put much more load on the CPU, so I guess a mirror is my best bet?

 

[BigDave]

Help members help you by posting the hardware specs for your server.
My confusion is...
When looking up your Dell T20, it seems to be listing a Xeon CPU which should
indeed have AES capability?
We have no knowledge of your situation, so without details, recommendations/suggestions
will have no worth. Sorry!

 

[Magnetz]

Sorry, missed that part. It's the G3220 pentium, not xeon

http://ark.intel.com/products/77773/Intel-Pentium-Processor-G3220-3M-Cache-3_00-GHz

 

[Robert Trevellyan]

2x1TB drives in a mirror with encryption that I use to store my backups

Why encrypted? Does your backup software not offer encryption?

Another mirror in the same pool?

This is the simplest approach.

 

[Magnetz]

I have my datasets backed up on a single 1TB external drive so it would be possible for me to rebuild using raidZ2 but it seems another mirror will probably be easier and more manageable.

I have 4x1TB and 1x2TB drives total and my aim is to have redundancy on the NAS and then have enough external storage to take a single copy

 

[Robert Trevellyan]

another mirror will probably be easier and more manageable.

Mirrors give you the greatest flexibility, but RAIDZ2 is more reliable. If you have more than 4 disks, the space overhead of mirrors may be a factor, but not in a 4-disk system.