Creating a vdev with a disk already containing data

[samesong]

I am putting together my first NAS, so I apologize for coming off as noobish (Not like my +1 post count didn't give that away already).

I ordered 8 4TB drives, and I currently have 2 4TB (NTFS) drives that are both nearly full.
I would like to create a Raidz2 vdev using all 10 4TB drives. Unfortunately I don't have anywhere to offload the data from the 2 4TB drives.

Is there a way to create a vdev with all 10 devices while retaining my data? I'm assuming this will be some command line work, but I'm not afraid to get my hands dirty. (And it's just a bunch of media, so no real harm if I screw up).

Thank you.

 

[enemy85]

Unfortunately not. Freenas is not designed to work that way. Once you create the pool, all the disks will be formatted with zfs file system and and everything on it will be cancelled.

 

[samesong]

Thanks for the reply.

The only solution I thought might work is the following:

1. Buy a couple of cheap 500GB HDDs
2. Create a 10 disk vdev with those two HDDs, giving me =~5TB of space
3. Copy over the data from the 2 4TB disks to my new pool
4. Switch the two 500GB drives with my two 4TB drives and expand the pool.

I could probably cull my data to fit onto the 5TB pool.

Would something like this work?

 

[enemy85]

Yes it would, another possible solution could be to create a 6disks raidz2 vdev now, and later buy other 2 4Tb hdds and create a second 6disks raidz2 vdev

 

[enemy85]

P.S. Consider that 10x500gb won't actually be 5 TiB... And u don't want to 100% fill your pool...

 

[Jailer]

You would only have the available space of around 3.8TB as you pool would be limited to the size of the smallest drives. You would effectively have a pool of 8 (+2 parity) 500GB drives. Your total storage pace would be the equivalent of a single 4TB drive until you replaced the 2 500GB drives with larger ones.

I would suggest purchasing a couple large usb drives to offload you data to, build your new pool with all your drives and then restore the data from the usb drives. You can then use the usb drives for backup.

 

[danb35]

I've seen posts here about creating a degraded vdev, which would allow you to do what you're describing. Standard disclaimers apply: It's dangerous, unsupported, there be dragons, etc. Here's one: https://forums.freenas.org/index.ph...dz-3-of-4-drives-i-e-to-allow-migration.7748/

 

[L]

The process I would use is to create a pool with 2 4 drive raidz or raidz2 vdevs. I would then copy in the data. I probably would try to buy 2 more drives and add another 4 drive set.

 

[samesong]

You would only have the available space of around 3.8TB as you pool would be limited to the size of the smallest drives. You would effectively have a pool of 8 (+2 parity) 500GB drives. Your total storage pace would be the equivalent of a single 4TB drive until you replaced the 2 500GB drives with larger ones.

I would suggest purchasing a couple large usb drives to offload you data to, build your new pool with all your drives and then restore the data from the usb drives. You can then use the usb drives for backup.

Right, I totally spaced the space required for parity! I actually have a 4TB external HDD I'm using as a Time Machine; I could temporarily repurpose that and another 2TB drive I have to temporarily hold my data. Thanks for your suggestion.

I've seen posts here about creating a degraded vdev, which would allow you to do what you're describing. Standard disclaimers apply: It's dangerous, unsupported, there be dragons, etc. Here's one: https://forums.freenas.org/index.ph...dz-3-of-4-drives-i-e-to-allow-migration.7748/

Yeah, that's way over my head. Pretty sure a dragon would eat me whole, and then my failed NAS system would burn my apartment down. Thanks for the idea though.

The process I would use is to create a pool with 2 4 drive raidz or raidz2 vdevs. I would then copy in the data. I probably would try to buy 2 more drives and add another 4 drive set.

Unfortunately I can't fit 12 drives, but if I could I would certainly consider doing this. Thanks for the suggestion.