Reconfiguring pool for fewer but larger disks

[deltabetacooper]

Currently I have a RAIDZ1 pool that consists of 4 3TB disks. I'm hoping to replace these four disks with three 8TB disks.

Before I do so, is it possible and what is the procedure?

Do I replace the disks one-by-one, resilvering all the way, until I've got all three 8TB disks in there, and then simply remove the remaining fourth 3TB disk from the array? My understanding is that the pool will be built with the remaining 3TB drive being the limiting one and my pool's storage won't have grown. If I remove that 3TB disk from the array, will the pool then grow to use the three bigger disks?

Thank you very much!

 

[Etorix]

This is NOT possible: A 4-wide raidz vdev will always have four disks. There's no way to shrink it.
If you remove one drive, it will work as a degraded vdev with no redundancy.

You may create a new pool with 3 drives, transfer data (replication) and then delete the old pool.
But note that using raidz1 with large drives is not recommended.