Adding disk to RAIDZ2 pool

[ChapterSevenSeeds]

I am running the latest version of TrueNAS Core and I have a single RAIDZ2 pool with 4x 6TB drives. I was doing some reading and it seems to me that adding another 6TB drive or two to this pool to make a 6x 6TB RAIDZ2 pool is currently impossible (without rebuilding the pool from scratch). Is this currently the case? All the threads I was reading about this were at least two years old. I also happened to read this: https://arstechnica.com/gadgets/2021/06/raidz-expansion-code-lands-in-openzfs-master/

My question is this: does anyone know where we are with this? Is it currently possible to add a disk to an existing RAIDZ2 pool? If not, does anyone have an update on when it will be a thing? I will soon be in the position to need to add a few more disks to this pool and I want to know if I can realistically wait until I can do it without having to migrate all my data off the pool, rebuild the pool, and restore my data.

 

[jgreco]

It is not currently possible. It may become possible at some point. Optimistic guesses would be "a year or two." Pragmatic guesses are more along the lines of "before the heat death of the universe." I'm sorry the news is not more joyous.

 

[sretalla]

Interesting, but I found this post on the way to finding the one I wanted to link for you (below) with a reference to that from 2015... shows you how slow things move: https://www.truenas.com/community/threads/allan-judes-zfs-slides-from-vbsdcon-2015.38186/

Here are the links I was wanting to share:

RAIDZ expansion, it's happening ... someday!

If you've not already seen it, RAIDZ expansion is happening. The OpenZFS project tweeted this earlier today. RAIDZ expansion (most requested ZFS feature ever?) is coming, courtesy of @freebsdfndation. Sneak preview at OpenZFS DevSummit! https://twitter.com/OpenZFS/status/921042446275944448 So...

www.truenas.com

Oh my!!! ZFS Expansion in the news...

https://arstechnica.com/gadgets/2021/06/raidz-expansion-code-lands-in-openzfs-master/ :cool:

www.truenas.com

Just to put that in context, TrueNAS 13 nightlies only employ OpenZFS 2.1 (which doesn't have the feature yet and won't), so don't hold your breath unless somebody decides to include a newer version before 13 drops for GA at some point (probably next year).