messed up; grow a ZFS RAIDz/backup RAW

[HankFlaggerty]

So I forgot a drive when I set up my RAIDz and now I cannot add it back into the RAIDz I created. I have to blow away everything and then start over.

I have two large (70TB and 16TB) raw disks that probably have <10TB of data actually written onto them.

What's the best way to backup/restore these so I can rebuild the entire thing? I assume that compression will actually take care of the unwritten space.

Setup an NFS server? Use an additional physical disk?

Just trying to get a primer on a game-plan here.

Thanks so much,
Henry

 

[aaron]

Use (multiple) mirror vdevs if you can afford to. They are much easier to modify later on (adding or removing disks from the mirror) and if you want to store VMs on that pool have a look at the ZFS RAID Level Considerations chapter in the admin guide.

Do you have another temp disk available? If you don't want to lose any snapshots or data integrity (checksums) you could set up a single disk pool there and use the send & recv functionality to send over that dataset to the temp pool/disk. Then recreate the original pool as you wanted and send the dataset back afterwards.

Using something like rsync to somewhere else that is not ZFS is of course also an option, but you will lose any snapshots you might have.

 

[HankFlaggerty]

Thanks Aaron,

Appreciate the response. I have temp disk available that can hold the amount of actual data written in the images, but not the full raw images. Is the send & recv functionality going to need all of the space or just the used data? Reading about it it seems to be the former unfortunately.

Would it be worth trying to convert to a different image format first?

 

[Dunuin]

Should only consume the space of the actual data.