Migrating from 2x500GB mirrored disks to 2x2TB mirrored

[tsteenbakkers]

I read some topics which covers this topic, but I’m not sure what happens if the disks are a different size. I thought in a mirrored setup disk should always be the same size. I have the following setup:

• 1 NVMe drive with TrueNAS scale installed
• 1 NVMe drive (1 TB) configured as a storage pool with only 1 disk (no replication needed)
• 2 x 500 GB SSD disks in a pool which are mirrored (so 500 Gb as storage)

I want to upgrade both 500GB SSD disks with 2 x SSD disks of 2 TB each. What’s the best way to do this without a restore of a backup.

Can I replace first one 500 GB disk with one new 2TB and then after re-silvering replace the other 500 GB disk with the second 2TB, with the result of 2TB of storage fully mirrored?

 

[sretalla]

Can I replace first one 500 GB disk with one new 2TB and then after re-silvering replace the other 500 GB disk with the second 2TB, with the result of 2TB of storage fully mirrored?

Exactly. That will work.

 

[tsteenbakkers]

I thought the disk sizes should always be the same. Won't TrueNAS 'shrink' the 2 TB disk to only 500 GB?

 

[Ericloewe]

Yes and no. Once the 500 GB disks have been replaced, the smallest disks will be 2 TB.

 

[tsteenbakkers]

Just finished the replacement and it works like a charm:

Followed these steps:

• Take disk 1 offline with the function Offline
• Physically removed disk 1 (500GB) and put the new disk in (2 TB)
• The 500GB shows offline and with the function Replace I selected the new 2TB
• The systems start resilvering
• After successfully resilvering use the function Detach to remove the 500GB from the list
• Take disk 2 offline with the function Offline
• Physically removed disk 2 (500GB) and put the new disk in (2 TB)
• The 500GB shows offline and with the function Replace I selected the new 2TB
• The systems start resilvering
• After successfully resilvering use the function Detach to remove the 500GB from the list
• After this the storage is increased: Usable Capacity:1.76 TiB

TrueNAS!