increase pool with new group?

[AJinNJ]

I have an existing Z1 pool with one group of 3 disks. I'd like to add more storage in general.

Can I add a second Z1 group with 3 disks to the existing pool and increase overall storage capacity? Are there downsides to doing this?

(Yes, I realize Z2 would be far better, but not ready to do that just now.)

Thanks for any tips/pointers.

-AJ

PS: I guess "group" = "vdev"?

(TrueNAS 12 U6)

 

[danb35]

PS: I guess "group" = "vdev"?

Yes, exactly. And yes, you can add vdevs to a pool--though once you do so, you can never remove them*. You'd use the "Extend pool" option in the GUI to do that.

As to downsides, when you have more than one vdev in the pool, they're all striped together, so that failure of one vdev means failure of the entire pool.

*More accurately, you can never remove vdevs from a pool unless the pool consists of only single-disk or mirrored vdevs. Since your existing vdev is RAIDZ1, this doesn't apply to you.

 

[AJinNJ]

Thanks @danb35 for the quick reply.

Adding a new vdev to the existing pool...will TrueNAS move existing data to the new vdev to "even out" the striping across the two vdev's? Just wondering if this is a performance impact during that effort and, maybe more importantly, is this an unnecessary strain on the existing disks?

Appreciate the insight!

 

[danb35]

will TrueNAS move existing data to the new vdev

Nope. The data load will generally even out over time.