I have a server with 6x18tb (16.37TiB) drives in RAIDz2, and due to hardware limitations, needed to start with 4 drives and expand later. Using 24.10 RC2, I extended my vdev twice, and during the second vdev expansion, I rebooted the system (as zfs documentation said it was safe to reboot during ex…

I am struggling with the concept on how the UI reports capacity as well :slight_smile: 9 x 12 TB raidz2. Started with 4 disks, expanded the remaining disks one by one with no errors, no reboots. “zpool list” shows 87 TB size, 29 TB free. UI shows “Usable Capacity: 42.5 TiB”, “Free Space: 13.63 Ti…

This is a known issue with no, current cure. Go by the CLI.

Thanks! - too late, I already ordered two more 12 TB drives :slight_smile: which should get me set for the next 100 years lol

Is there work being done to fix this, or just SOL for the time being?

Just search for RAID-Zx-expansion tag and do some reading. CLI is most accurate reporting currently.

Unfortunately this is still an issue in 25.04 I just expanded a 4 wide raidz2 to 5 wide and was trying to figure out why almost an entire drives worth of available capacity was missing

I don’t know if this is an issue that will be fixed. You can read the other threads with the RAID-Zx-expansion tags to get an idea of what is involved with how the expansion happens and ZFS.

Maybe not fully fixed, but we are working on a nice change to zfs that will mitigate this and allow easier way to fix the reporting down the road, among other nice benefits :slight_smile: Introduce zfs rewrite subcommand master ←…

So in its current state it only removes the need to run a rebalance script on an expanded vdev, but doesn’t fix incorrect drive space reporting correct? But you’re saying it might make fixing the space reporting on an expanded vdev easier once that bug is taken on?

24.10 RC2 Raidz expansion caused miscalculated available storage

TrueNAS General

imkidd57 February 8, 2025, 6:51am 148

… and use zpool list report info, not zfs list.

Help understanding pool size after vdev expansion

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24.10 RC2 Raidz expansion caused miscalculated available storage

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