Re: Can I add a raidz vdev as a mirror of existing vdevs

From: Mel Pilgrim <list_freebsd_at_bluerosetech.com>
Date: Sun, 09 Jan 2022 04:32:57 UTC 
On 2022-01-08 18:52, Paul Procacci wrote:
> Found an answer to this on facebook of all places .......
> 
> https://www.facebook.com/notes/unix-in-egypt/converting-zfs-2-way-mirror-to-a-raidz-array-wihtout-losing-data/10151919826687996/ 
> <https://www.facebook.com/notes/unix-in-egypt/converting-zfs-2-way-mirror-to-a-raidz-array-wihtout-losing-data/10151919826687996/>
> 
> My initial reaction was going to be 'no'....but after reading this, it 
> does seem it is possible.
> I've never done it personally, but with proper backups .... why not?

The degraded pool shenanigans described are to avoid needing separate 
disks for the old and new structure, but that's exactly what I have, so 
I can skip all of that.  With those bits skipped, that becomes a regular 
exercise of creating a new pool and streaming snapshots, which requires 
downtime.