Hello guys, im sorry to ask because this question was probably answered 100 times, but i read different answers online regarding the change from a mirror to a raidz1 vdev, especially after recent truenas updates. I currently run 2x4tb drives in a mirror. Right now, i have the chance to get 4x8tb h…

How many sata slots do you have access to in total? (please specify free/in-use)

Post your full hardware specs. Possible options would be based off how many drives can be attached at one time. Changes like you stated, usually need backup of data, destroy pool, create pool in new layout and then restore data from backup

[image] Simon_Kirzinger: Can i add a new vdev to my pool and then remove the mirror? No. [image] Simon_Kirzinger: If not, is there any other way to replace the mirror without rebuilding the whole pool structure? Also no, unfortunately. vdev removal is only available when all vdevs ar…

Only 4 and 1 is used for a cache ssd and 2 for the current hard drives. But i can add an HBA temporarily to increase it!

I should be able to connect all with an HBA. Is there a step by step guide on how to do this? I run a SMB share and a few apps (Nextcloud, Nginx, Tailscale, …) on the existing pool. As far as i saw, i have to create a new Pool with all the new drives, then do a recursive Replication from the old t…

[image] Simon_Kirzinger: the change from a mirror to a raidz1 vdev, That is a textbook definition of a pool rebuild. [image] Simon_Kirzinger: Can i add a new vdev to my pool and then remove the mirror? No. Any raidz member in a pool prevents ((meta)data) vdev removal. Create your new…

[image] Simon_Kirzinger: As far as i saw, i have to create a new Pool with all the new drives, then do a recursive Replication from the old to the new pool. After that, i have to transfer the data from the apps to the new pool and change the appdata paths to the new pool. Does that sound right? …

thanks for the guide, really appreciate it!

You can also do 3. and 4. from the GUI. There is a resource for 7.

Change from Mirror to Raidz1 without pool rebuild

TrueNAS General

Fleshmauler July 14, 2026, 7:16pm 11

http://forums.truenas.com/t/howto-rename-a-zfs-pool/

to save a step

Topic		Replies	Views
Move 2TB Mirror to New RAIDZ2 TrueNAS General	15	500	February 7, 2025
Convert raidz1 to raidz2? TrueNAS General	11	1021	July 18, 2025
Migrating from mirrors to RAIDZ2 TrueNAS General Hardware , ZFS	7	268	July 10, 2025
Help validating pool update (adding vdev and removing old vdev) TrueNAS General CORE , ZFS	5	199	April 22, 2024
Upgrading Mirror to RaidZ1 TrueNAS General	1	331	February 25, 2025

Change from Mirror to Raidz1 without pool rebuild

Related topics