Advice for temporarily storing data while adding disk to raidz2

[lukeren]

I have a 5 disk raidz2 that I would like to add a disk to.
Since we're a ways off getting support for adding disks to existing volumes, I'll have to move the data somewhere, destroy the volume and recreate it.
I've dragged home a server from work, that has 22 x 900GB SAS drives. The controller however, is RAID (ServeRAID M5210), not just a HBA.
I'd like to use this for temporary storage and do a zfs send/recv since that would make it a lot simpler to put the data back, but would that be advisable when freenas won't be in direct control of the drives?
Is there another option I'm not seeing?

 

[dir_d]

I would just use rsync to the temp server

 

[melloa]

I would just use rsync to the temp server

Assuming the temp server will be running an OS with rsync, yes.

As the OP doesn't have a HBA in IT mode, options are limited to one big raid mounted to a linux or freebsd or another OS, even boot freenas and create the pool from that raid. Recommended? No, but doable.

 

[Heracles]

Hey lukeren,

It is clear that a hardware raid controller is not recommended for FreeNAS, but in your case, you can protect youself. You did not mentioned how big or loaded is your actual RaidZ2, so I can only assume here...

What I would suggest is to use the hardware raid and split your 22 drives in two virtual drives. Once done, you install FreeNAS and you create two pools, one out of each virtual drive.

The risk with FreeNAS on hardware raid is whenever an access is interrupted for any reason. So I would do a first ZFS send to the first pool and once done, unmount the pool. After that, I would do a second ZFS send to the second pool and again, unmount it.

After ZFS has been successful to send and receive and unmount the pool, you can be pretty sure that all operations are over and completed successfully. After that, you destroy your original pool and re-create it. Once re-created, you remount one of your backup pool and ZFS send it to the new pool. If anything goes wrong, you still have the second pool that should remain safe.

RSync is great for syncing the actual files, but for snapshots and more, ZFS send / receive is better.

Good luck re-doing your pool,

 

[lukeren]

I think I've found another way.
A lot of the data is files in a few single directories, so it's easy to move them out to a RAID 10 on the M5210 and keep them secure.
I can then set up a RAIDZ on another computer to which I can do my send/recv so I keep my permissions and jails as they are. This second computer doesn't have ECC, so I'm hoping for calm spaceweather :P

Didn't realize I had enough harddrives to set up another freenas box, so sorry to waste you time :(