New to FreeNAS, and RAID...Not sure which option

[screaming_slave]

All,
I am trying to set up a FreeNAS box, but am unsure of which HDD configuration to go with. My goal is to have two 'volumes' (?) with 6TB each, that are mirrored.

My HDD are as follows:
Two 3TB (toshiba)
Two 2TB (WD)
Two 1TB (??-in use)

It is my understanding that I can put one of each size HDD in each volume, and mirror them. I'm just not sure which configuration options, and I've never done RAID before. I have a core2quad, 6gb RAM, gigabyte MB. Thanks for any assistance!!

 

[warri]

You want 3 mirrored vdevs in your pool, each mirror containing of two disks of the same size. You'll end up with one pool (=volume) you can access. If you are new to FreeNAS, read the manual (especially the section about creating pools) and give it a try on a fresh system or VM until you feel familiar with everything.

 

[gpsguy]

While you're reading the manual, check the memory requirements.

 

[ZFS Noob]

You need more memory or there are edge cases where memory exhaustion will cause FreeNAS to eat your pool. Get more memory.

While you're at it, make sure you're running ECC memory, because while ZFS does amazing things to protect your data, it's blind to memory errors and a stuck bit will cause ZFS to overwrite your pool with garbage.

What you're probably wanting to do, if I'm reading your correctly, is:

• mirror the 3TB drives into one vdev. This will give you 3TB of storage that can handle 1 drive loss.
• mirror the 2TB drives into another vdev. Either of these drives can fail and your data will be fine.
• Mirror the 1TB drives, same.

In the end when you add them to a pool the pool will stripe across all three vdevs, yielding 3 + 2 + 1 TB of space.