Pre-sale question on zvol upgrade

[IDtheTarget]

Hello!

I'm getting ready to buy the FreeNAS mini XL. I already have 5 3-TB WD Red drives that I'd purchased last year but haven't used yet. after reading as much as I've been able to on this forum, I've determined that I want to run a RAID-z2. I'm going to have a bunch of stuff that I just do not want to risk losing.

Now, I need to purchase three new drives. I know that if I purchase 3 6-TB drives, when I create the zvol only 3TB of each of those drives will be used. However, if I replace one 3-TB drive with a 6-TB drive each couple of months, eventually I'll have all 6-TB drives. At that point, will FreeNAS upgrade the space on the zvol, or will I have to do it manually? And in either case, will my data be safe or will I need to (somehow) back it up off the XL and then re-load it after the space increase?

I'm asking because, if it's that big a pain, I'll just buy 3TB drives and worry about buying bigger drives when at some point in the future when I win the lottery.

Thanks!

 

[nojohnny101]

Welcome to the forums!

Now, I need to purchase three new drives. I know that if I purchase 3 6-TB drives, when I create the zvol only 3TB of each of those drives will be used.

That's correct.

However, if I replace one 3-TB drive with a 6-TB drive each couple of months, eventually I'll have all 6-TB drives.

Correct.

At that point, will FreeNAS upgrade the space on the zvol, or will I have to do it manually? And in either case, will my data be safe or will I need to (somehow) back it up off the XL and then re-load it after the space increase?

You will not have to off-load your data, the volume should auto-expand. You can view the relevant section in the manual for an explanation in detail: FreeNAS Manual Aut0-Expand (sections 8.1.11 & 8.1.12)

Also, remember that raidz functionally is NOT a substation for having a backup. If I were you, I would backup my crucial data that I could not afford to lose to an external drive, maybe just a cheap external drive. There are many events where raidz does not protect you like electrical surges, theft, fire, etc.

Good luck!

 

[wblock]

That is a 9.3 doc, here is the 9.10 version: http://doc.freenas.org/9.10/storage.html#replacing-drives-to-grow-a-zfs-pool

Personally, it always seems to save me time to just start out with more storage in the first place.

 

[IDtheTarget]

Personally, it always seems to save me time to just start out with more storage in the first place.

I agree. Unfortunately I don't have the extra $1,900 for 8 6-TB drives right now. I'm at the limit of my budget with the Mini XL and the 3 6-TB drives. though now I wonder if it wouldn't be a good idea to buy one more as a "cold spare"... *sigh*

 

[wblock]

I understand. For what it's worth, FreeNAS 9.10 is supposed to autoexpand when the individual disks have all been replaced with larger disks.