Move data protection tasks to new pool?

TrueNAS General
1

In Goldeye 25.10.2, I have a 3x mirror pool consisting of 3x12TB Seagate Ironwolf Pro HDDs, for 12TB capacity. It’s starting to get a bit tight, almost 70% full, so I’m considering buying another 12TB Ironwolf Pro and moving to a 4 drive z2 pool with 24TB capacity. However, as I understand it, there is no way to change the pool in place from a 3x mirror to a 4 drive Z2. (Correct me if I’m wrong.)

Therefore, I believe I’m going to need to destroy the existing mirror pool, create the new z2 pool, and restore the data from backups. I’m not worried about data loss as I have numerous backups.

The problem, however, is that I have approximately 25 data protection tasks set up in the Truenas UI involving this pool, including replication, rsync over ssh, cloud backup, and snapshots. These data protection tasks are finely tuned, and it’s taken me years to get them set up how I want. Is there a way to migrate the data protection tasks from the old pool to the new pool? Failing this, is there a systematic way to print all the tasks and their parameters so that I can easily type them back in once the new pool is created?

2

Its possible to use your existing disks and some sparse files to avoid having to buy additional disks. But a direct conversion is not possible. There be dragons…

3

Is there a reason you are choosing a 4 wide Raid-Z2 over converting your 3 Wide Mirror into a two mirror pairs using two VDEVs? (removing a drive from 3 wide mirror and adding a 2 drive mirror VDEV to your current pool) Do you require two drives of redundancy per VDEV?

MyPool
2 wide 12TB VDEV1
2 wide 12TB VDEV2

4

Is there a reason you are choosing a 4 wide Raid-Z2 over converting your 3 Wide Mirror into a two mirror pairs using two VDEVs?

Yes. A 2-VDEV setup will fail and lose all data if the wrong two drives (in the same VDEV) fail, whereas with a 4 drive Z2 VDEV, any two drives can fail, and the pool is still intact, with no data loss. In other words, a 4 drive Z2 has better redundancy. My main goal is avoiding data loss. The other things about the architecture, like write speed, are of less relevance in my small home setup.