ZFS - Add 4th disk to the RAIDZ1

[Martini]

Hi all,

is there any possibility to add a new disk to the RAIDZ1 which is created from 3 volumes (same size) in order to extend the RAIDZ1 capacity of the zfspool?

Is it possible to do it online?

# zpool status

  pool: rpool
 state: ONLINE
  scan: resilvered 1.76M in 00:00:01 with 0 errors on Wed Aug 31 13:35:43 2022
config:

    NAME                              STATE     READ WRITE CKSUM
    rpool                             ONLINE       0     0     0
      raidz1-0                        ONLINE       0     0     0
        scsi-3500003997808b838-part3  ONLINE       0     0     0
        scsi-3500003997808b83c-part3  ONLINE       0     0     0
        scsi-3500003997808b898-part3  ONLINE       0     0     0

The 4th disk which I would like to add to the pool has the same capacity / same type.

I'm using the Proxmox VE 7.2-3.

Thank you

 

[Dunuin]

No, thats not a feature ZFS supports yet. You will have to backup all data, destroy that pool, recreate it with 4 disks and then restore the data. You can backup even snapshots when using ZFS replication to move data between two pools...but of cause you need another ZFS pool for that with atleast the same amount of free space.
If you don't got that and you don't want alot of downtime your best option would be to buy 3 more drives and add them as another vdev, so you get a 6 disk striped raidz1.

 

[Martini]

Let's hope that such kind of feature will be available soon in ZFS.

Anyway, thank you for the answer and have a nice day.

 

[Neobin]

For reference:
https://github.com/openzfs/zfs/pull/12225