ZFS Pool Upgrade

[Tony Self]

Hi guys. I am planning some hardware upgrades to my TrueNAS Core server. My first phase is to upgrade my 8 drive HGST 8TB Z2 pool. I am looking at upgrading with Seagate Exos X18 16TB drives. I would be interested whether you think this is a good choice.

The other question I have concerns the replaced drives. Can they be imported into another TrueNAS Core system with all the data intact or will they have to be wiped and start from scratch?

Thanks for your comments in advance.

Tony Self

 

[winnielinnie]

Can they be imported into another TrueNAS Core system with all the data intact or will they have to be wiped and start from scratch?

If all 8 drives are available, and the pool has been cleanly exported from the previous system, I don't see why not?

(This assumes you're replicating the old pool --> to the --> new pool.)


However, if you're doing a "one-by-one" replacement of the old drives with the new drives (to "upgrade your pool"), this might in fact make the old drives' pool "unimportable".

Which is actually an interesting question I never considered.


Is it possible to do a "one-by-one", step-by-step replacement/resilver of a pool, and still keep the original pool intact on the original drives when finished?

I would suspect this isn't possible, since during the process the remaining old drives will have their pool metadata constantly updating as you replace and resilver the new drives into the pool.

 

[Tony Self]

I suppose the only way to duplicate the drives one by one would be to close down TrueNAS and use Clonezilla to duplicate the drives.

 

[Davvo]

If you have 2 systems, you can just zfs send | zfs receive.

 

[kjacques1]

If all 8 drives are available, and the pool has been cleanly exported from the previous system, I don't see why not?

(This assumes you're replicating the old pool --> to the --> new pool.)


However, if you're doing a "one-by-one" replacement of the old drives with the new drives (to "upgrade your pool"), this might in fact make the old drives' pool "unimportable".

Which is actually an interesting question I never considered.


Is it possible to do a "one-by-one", step-by-step replacement/resilver of a pool, and still keep the original pool intact on the original drives when finished?

I would suspect this isn't possible, since during the process the remaining old drives will have their pool metadata constantly updating as you replace and resilver the new drives into the pool.

I can confirm that after just replacing my four 4tb drives with 8tb ones and putting the old 4tb drives into another TrueNAS server, I was unable to import the pool on it.

 

[winnielinnie]

That's what I suspected.