Adding spare disks afterwards deletes existing pool?

[andimattes]

Hi everyone!

I'm currently using TrueNAS Scale 23.10.0.1 with 3x8TB in RAIDz1. I now want to add 2x8TB as spare disks if some of the existing disks fail.
When clicking on "Update Pool" to confirm the changes, I receive the following warning:

I assume that only the new added drives will be formatted, is this correct? I really don't want my whole pool to be formatted since I have important data there.

Thank you for every help!

 

[Etorix]

Correct. Take the scare as reminder that "ZFS is not a backup": If you have "important data" in there, you should have a backup.

 

[andimattes]

Correct. Take the scare as reminder that "ZFS is not a backup": If you have "important data" in there, you should have a backup.

Thank you very much for the advice! I'm quite new to ZFS and thought that spare disks == backup. I looked into the periodic snapshot tasks as this seems more like the backup I want to have. Unfortunately I did not find a way to make a snapshot of my current storage-pool and back it up to a different pool e.g. backup-pool. Can this be done in TrueNAS Scale in some way?

 

[Redcoat]

Unfortunately I did not find a way to make a snapshot of my current storage-pool and back it up to a different pool e.g. backup-pool.

Looks like what you want is a replication task (which is based on snapshots): https://www.truenas.com/docs/scale/scaletutorials/dataprotection/replication/localreplicationscale/