How to add new disk to ZFS pool?

[Maher Khalil]

Is it possible to add new disks to the existing pools without building the arrays?
if yes, how?

 

[aaron]

It is, but can you please post some infos about your current pool and how you would like to add new disks? This way we can avoid any, potentially disastrous, misunderstanding

 

[Maher Khalil]

I have installed proxmox in zfs raid mirror 2 x 250GB NVMe => first pool
I have created second zfs pool as raid mirror 2 x 1.6 TB SSD => second pool
I have created third zfs pool as raidz1 4 x 2.4 TB HDD ==== => third pool

 

[aaron]

So which pool would you like to add new disks to and in what manner?

The output of zpool status would also be nice

 

[Maher Khalil]

I got to know now that I cannot add disks to zfs pool but can create new pool only
right?

 

[Dunuin]

You can add new drives to your pools but how to do it and what the limitations are depends on the actual pool setup.
For example adding disks to your first pool is complicated because ZFS is only used on one partition and stuff like the bootloader partition and so on need to be copied manually.
For the second pool you can only add drives in pairs. So you would need to add a additional mirror to get a 4 disk striped mirror.
For the third pool you could add single disks but that will only increase the capacity and not the performance. If you want the full performance and capacity you would have to destroy and recreate that raidz1 pool.

 

[Maher Khalil]

understood
one more question please is when I do reinstall for proxmox on the first pool disks, the new installation will not detect the second pool and third pool.
How to arrange for all pools detection after new installation?

 

[Dunuin]

You need to import your pools first (zpool import) and then add these pools as a ZFS storage to your PVE (in webUI under: Datacenter -> Storage -> Add -> ZFS)

 

[Maher Khalil]

You need to import your pools first (zpool import) and then add these pools as a ZFS storage to your PVE (in webUI under: Datacenter -> Storage -> Add -> ZFS)

I will test this in new installation today

 

[Dunuin]

Don't forget to backup your /etc folder. Your VM/LXC disks on the other ZFS pools are useless without the VM/LXC config files in "/etc/pve/qemu-server" and "/etc/pve/lxc".

 

[Maher Khalil]

So before any reinstall I have to backup these files?

 

[Dunuin]

Yes and I would backup them also on an regular basis in case your system disk suddenly dies.

 

[Maher Khalil]

So backing up these to files is enough?
/etc/pve/qemu-server
+
/etc/pve/lxc

 

[Dunuin]

I would backup the complete /etc folder.