I know that this is a frequent topic. However, I have not seen one taking into account the more recent iterations of Goldeye, which have, the way I understand it, made the process easier. Still, it is not obvious to me how to go about changing my 2-drive mirror pool to a 4-drive RAIDZ2 pool with tw…

Backup and rebuild, no other option… Edit: You could break the mirror, create a raidz2 with 3 disks, sync your data over and add the 4th disk to the raidz2, but you’d still have the space reporting bug after expansion…

Backup, destroy, recreate, restore. There is no process to change a mirror into a RAIDZ2. You could of course add the two new disks as another mirror VDEV to the same pool. Plus points: seamless, no copying/moving of data same capacity/redundancy ratio pool will be slightly faster in terms of IOP…

How to best expand a mirror to RAIDZ2 on Goldeye

TrueNAS General

DominikHoffmann January 9, 2026, 12:39am 4

I started a new topic with my question about how to accomplish my goal through a different approach.

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How to best expand a mirror to RAIDZ2 on Goldeye

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