How to upgrade to larger drives

TrueNAS General
1

I feel like an idiot asking this, but they don’t make it easy to find info in the documentation, and the AI was no help.

I’m currently running 4x2tb Seagate Barracuda drives. I know that Barracudas are not recommended for this use, and as such, I’ve bought 2x8tb WD Red drives to replace them. Trouble is, I can’t seem to add a vdev to the pool. I’m thinking I need to do one disk at a time, and let it resilver, but when I try to add the disk to the pool, I have no options under width and vdev, so I can’t save and continue. I’ve formatted the disk, ext4, but still no luck. I’ve also tried FAT.

What am I doing wrong. I’m sure I’m missing something obvious.

2

There are 3 ways to increase pool size:

  1. Add a new vDev.
  2. Replace existing drives with larger drives. When all drives in a vDev, (not pool, but vDev), are replaced, that vDev will grow.
  3. If using RAID-Zx, use the new feature of RAID-Zx expansion.

So, what you do depends on what you want to achieve.

For option 2, check the documentation site for disk replacement.

TrueNAS does not use EXT4 nor FAT, and formatting the disk might have added some minor problems.

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3

Then go to Storage > Drives, select a drive, click “Replace” and let ZFS do then job.
Repeat.

4

Before doing it I’d check if those wd red drives are smr or cmr drives. Smr drives a not a good fit for using with zfs

5

In the strict sense of the word “replacing” 4 disks with 2 other disks is not possible.

Since you cannot remove VDEVs from a pool, you need to create a new pool with those new 2 drives, and then move the data to this new pool.

3 Likes
6

Before using them, I’d suggest to perform a long S.M.A.R.T. test (it could take 12 hours).
It is advisable to leave them unformatted. As you formatted them as Ext4/FAT, I am not sure how TrueNAS will treat them, but I believe that it will reformat them to ZFS. If not, remove any partition that you made there.
Then, you can follow advices above from @etorix or @ChrisRJ .

7

A few days of badblocks -ws doing its thing followed by a long SMART test will test the drives and take care of formatting.
Then if the old pool is raidz, follow @ChrisRJ and replicate to a new pool; if it is a mirror stripe, you may either follow @ChrisRJ anyway or replace one vdev and then remove the other from GUI (make sure you have no cloned blocks or are running a version of TrueNAS which has the vdev removal fix!)

1 Like
8

Thank you everyone. I’ll try this later when I get a chance and let you know how it goes.

9

So I tried option 3. I took my first drive out, and replaced it with an 8tb drive, then I clicked on expand, and chose expand to fit available size. Didn’t work. It still tells me I have an unassigned disk, at 7.28tb. I try adding that disk to the existing pool, and under Data, it lets me choose the 7.28tb disk, but then under width and number of vdevs it says no options. I can’t add the disk to the pool, so it won’t expand the pool into that disk.

10

In order to advise you further, we need the pool layout.

Are you using 2 x 2 way Mirrors?
Or a 4 column RAID-Zx?

11

Actually, I think I got it worked out. Part of the problem was a loose sata cable. Other part was that I was only doing one drive, not two. So now, I’ve added both 8tb drives, created a new pool, and am replicating the old pool onto the new pool. Wish me luck. And thank you for your continued help, Arwen.