Installing larger drives (can't be this easy)

[Penbrock]

I just want to make sure it is this simple and I will not loose my data.
I have 2 3T drives in a mirror that is full. So I want to go to 2 6T drives.

It can't be as simple as I am reading, just install the new HDD and go replace one of the drives under Volume Status.
When it is resilvered, do the same for the other drive.

from what I read the Freenas 11 will see the larger drives and automaticly expand the volume???? I have a hard time thinking it will be that easy

 

[garm]

Why?

 

[HoneyBadger]

It is in fact that simple.

Do you have the room to install the 2x6TB drives at the same time as the 2x3TB ones? Then you could migrate all of the data at once without having to do two resilvering operations.

 

[Penbrock]

It is in fact that simple.

Do you have the room to install the 2x6TB drives at the same time as the 2x3TB ones? Then you could migrate all of the data at once without having to do two resilvering operations.

Yes I do (I was going to plug them both in and replace one at a time)
By migrate do you mean just copy? or is there a command I'm missing that will keep all of the ownership and stuff

 

[anmnz]

Yes I do (I was going to plug them both in and replace one at a time)
By migrate do you mean just copy? or is there a command I'm missing that will keep all of the ownership and stuff

You can do this:

Plug in the two new disks. Attach them both to the existing mirror. (Be careful to "attach" them to the mirror and not to "add" them as new separate devices to the pool.) You now have a 4-way mirror vdev, and the two new disks will immediately start resilvering.

When they have finished resilvering, detach the two old disks from the mirror. The vdev will automatically expand to the size of the remaining disks.

 

[garm]

No need to do that.. just replace the existing drives..

 

[anmnz]

It kind of amounts to the same thing, but the 4-way mirror does have more wow factor. :)

 

[garm]

While you replace at some point you will be there any way. Attaching/detaching has bigger disaster potential..

 

[HoneyBadger]

Yes I do (I was going to plug them both in and replace one at a time)
By migrate do you mean just copy? or is there a command I'm missing that will keep all of the ownership and stuff

I'm assuming you're going to remove the 3TB drives when you're done and use them in another system; otherwise, just add the 2x6TB drives to your existing mirror, and you'll end up with a net result of 9TB of usable space (although not balanced across the drives in the slightest)

If you are going to pull the drives and want to be left with only 2x6TB, doing the one-replace-at-a-time might be the best solution. There's a long thread detailing another user's attempts to use the zfs send and zfs recv commands to locally replicate a snapshot; it seems like it was a rather difficult process:

https://forums.freenas.org/index.ph...-current-pools-to-a-10tb-transfer-disk.59852/

So I would do the "one REPLACE at a time" following documentation section 8.1.11
http://doc.freenas.org/11/storage.html#replacing-drives-to-grow-a-zfs-pool

Notably, do not follow the instructions in 8.1.10 for replacing a failed drive. Those instructions have you taking the old drive OFFLINE first, rather than at the end, which opens you up to a potential situation where the one remaining side of the mirror vdev could fail (or just fail to read a sector) and cause data loss.

Do one at a time, when you've replaced both drives, shut down and pull the 3TBs for their new home, and boot back up. Assuming your FreeNAS version and pool are up-to-date, it should automatically show the new space in the GUI.