4x ZFS Mirror to 1x bigger ZFS Mirror

[synci]

Hey guys,

i have 4 ZFS mirrors with 12TB total space (2 drives each) and want to make just 1 ZFS mirror with new bigger drives with 14TB total.

What is the easiest way to do this ? (I can not create a fifth mirror because the SATA ports are fully used)

My idea was to replace at first 1 drive from mirror1 with a new drive and wait till rebuild/resilver is complete.
Then i replace the second drive from this mirror and wait again till rebuild/resilver is complete.

But can i transfer the files from the other 3 remaining mirrors to the new one ?
(It is one dataset for all 4 mirrors, lika a pool, i dont know how to just access files from mirror3 for example)

Thanks !

Best regards,
Matthias

 

[leesteken]

Assuming you won't be actively using those mirrors, you might as well take out one drive of each mirror. Connect both new disks and make a new mirror and copy all files to it. This way, you'll also have a copy of your original setup (assuming no drive dies while disconnected) in case something goes wrong. Or just connect one new drive, copy all files from all old drives/mirrors, and then add the other new drive (remove everything else) to form a new mirror? Maybe your original way is slightly safer on the other mirrors in case of failure of one of the disks? I'm not sure it really matters.
PS: make sure you scrub your mirrors before removing one of their drives.

 

[apoc]

I'd get myself an additional 2 port sata controller and create a new pool on the new disks.
Then transfer the datasets with zfs sent and receive. If you don't have a pcie slot at hand that's obviously not going to work in which case you indeed could remove one or even 2 disks from the existing pool by degrading/detaching a mirrored disk to achieve the same. But it is more risky.
A scrub should be definetly be issued and run before you remove your redundancies.

 

[synci]

Thank you both for the great answers !
I dont even thinked about to simply put in a HBA for this, i have one and thats what i will do, great

Thanks a lot !