Cloning smaller hard drive to larger hard drive and swapping.

[suivax]

Hi folks,

Just like the title says, I'd like to expand my storage by upgrading from 4 TB drives to 8 TB drives. I pulled a 4 TB hard drive out and resilvered an 8TB drive, thinking I would just do that with the 4 drives. It took 48 hours to resilver one drive, so I'd like to explore the idea of setting a drive to offline, pull it out and clone it with an Inateck USB 3.0 to SATA Dual-Bay USB 3.0 hard drive docking station with offline clone function.

1) Is this possible?
2) If it is, after the drive has been cloned and put back in, what will happen when I choose replace, do the drop down to 8TB and click ok? Will it see the data and think everything is fine, or will it go through a resilver process to verify the data matches? I'm not sure what will happen.
3) What would happen if I just stuck the disk back in and put it online without using the replace option?

I appreciate any assistance you can offer.

Thanks,
Jeff

 

[kdragon75]

cloning and resilvering are very different. Resilvering will not clone the partition table and that's a good thing. The GUI replace disk will repartition the disk for the new size and ZFS will resilver the data.

 

[suivax]

cloning and resilvering are very different. Resilvering will not clone the partition table and that's a good thing. The GUI replace disk will repartition the disk for the new size and ZFS will resilver the data.

Hi kdragon75,

I know resilvering and cloning are different. That's not what I'm asking. I read from another post that replacing all the disks with larger drives and letting them go through the resilver process, that the ZFS pool would expand once all drives were replaced in RAIDZ1. I'm interested in exploring the options in my original post as it took too long for one drive. I can clone a drive in 8 hours vs. 48 hours to resilver. How will FreeNAS and ZFS handle this is what I'm asking.. Is it possible?

 

[suivax]

Ok, after looking again, you don't have the option of bringing the drive back online. Replace seems to be the only option after taking it offline, unless FreeNAS detects a different serial number and knows it's not the same drive. So, will it speed the process up to clone the drive vs. inserting a bare drive? Will it error out and force you to wipe it? How will FreeNAS handle that?

Thanks!

 

[Jurgen Segaert]

Did you consider using the procedure outlined in the manual?

8.1.11. Replacing Drives to Grow a ZFS Pool

 

[Jailer]

If you have enough SATA ports, connect the new drive and replace it before you remove the old drive. This will keep your redundancy while reslivering the new drive and it should take less time to complete.

 

[suivax]

Hi Jurgen, yeah, that's exactly what I'm doing now but wanted to see if other users had experience with cloning drives to speed up the process.

 

[kdragon75]

How will FreeNAS and ZFS handle this is what I'm asking.. Is it possible?

It will handle it poorly. I don't know how the middleware was written with regard to identifying new disks. The issue is that you have a foreign disk and serial number but the old GPTID numbers. If thats not an issue, you still need to manually edit the partitions to reflect the new sizes. This includes moving the swap partition.
Is it possible? Yes.
Is it feasible? Maybe.
Will it save time? Maybe.
Will it be more work? Yes.
Is it advisable? NO.

Dont forget to export the pool and mark it read only before mucking with the partition tables. Unless you like to live in a zone of.... danger?

 

[kdragon75]

One might even call this a danger zone!

 

[suivax]

lol, fair enough kdragon. Guess I'll just be delayed a bit. I figured there might also be an issue with the metadata.

 

[Stux]

If you had lots of bays you could replace all the drives at once...

 

[suivax]

If you had lots of bays you could replace all the drives at once...

Yeah, I've only got 4 hot swappable bays in this 1U chassis. Adding a bunch of disks and doing data replication would certainly be an option if I had more.. Thanks!

 

[Stux]

Yeah, I've only got 4 hot swappable bays in this 1U chassis. Adding a bunch of disks and doing data replication would certainly be an option if I had more.. Thanks!

No. You can literally ‘replace’ all the disks at once