That's neat! I didn't know there was a way to do this while maintaining data redundancy.
> Step 1: Borrow one disk to create a RAIDZ2 pool
> To begin, I remove one disk from my original RAIDZ1 pool, leaving it in a degraded state.
Oh, there isn't. :facepalm:
I have backups, so I was prepared for data loss if the pool failed.
Is this any riskier than recovering from a single disk failure on a RAIDZ1 pool?
1. Build new RAIDZ2 pool with all your disks that you plan to use. 2. Restore backup to the new pool.
I keep a backup too and so this is how I move to a new larger ZPOOL with a new layout.
Either you have to do this because you don't have a backup, and so this is risky. Or you don't need to do this because you have a backup and can just build your new pool and restore your data from the backup.
With your extra drive solution, I still have to recreate all my datasets and shares, whereas in my solution, they migrated intact, and I still had backups in case of pool failure. I could zfs send into a giant file on the 18 TB drive, but I'd be reticent to do that because it's just an opaque file that I can't verify will successfully restore. Whereas with my solution, I had the two pools running side by side and could verify everything restored successfully onto the new pool before blowing away the old pool.
Why did you pull a drive from your RAIDZ1 to purposefully degrade it?
I am not sure why you keep saying 18TB. Your drives are 8TB. I am suggesting that you should have simply bought another 8TB disk so you wouldn't have to degrade your RAIDZ1.
Yes, I agree I could have reduced the risk of pool failure if I bought an extra 8 TB disk and not degraded the pool.
So, it came down to do I for sure spend an extra $120 on an extra drive or do I just take the <1% chance that one of my three other disks fails in a 6-hour window while I'm migrating data. I took the chance, but I also had my data backed up in cloud storage at the file level in case there was a pool failure.
In other words, it wasn't worth $120 to me to avoid a <1% risk that I'd have 8ish hours of hassle of recovering from cloud backup after a pool failure.
mtlynch•4h ago