HELP: how to take a raidz3 pool data drive and change it to a spare

[spamail00]

I want to take a allready zfs raidz3 pool data drive and change it in to a spare with out degrading the pool. Is this possible?

[Farout]

You mean going from RAIDZ3 to RAIDZ2 + spare ?

No, thats not possible.

[Arwen]

Neither is removing a disk / column from a RAID-Zx vDev possible.

[etorix]

Backup. Destroy. Restore.