My current setup is 3 4TB drives totaling 12TB with 2x 4TB parity. I want to increase the capacity and swap the drives as they are getting old. I have 3 new Toshiba 16TB drives to be mounted as 32TB total, with 16 TB parity. However I cannot add these. 

 

I tried to swap one of my parity drives with one new 16 TB and let it rebuild. When wanting to add the second 16TB to the drive pool, I got the "Disk in parity slot is not biggest"-error.

 

I removed the new parity 16TB, started the array, and are now at 3+1 drives

 

I searched around the forums, installed UD plugin, removed the partition from the drives and tried adding one of them to parity and one to the drive pool, but I still get the error. I don't understand why, as the drives look identical in size (see below). Any suggestions on how to proceed?

 

 

root@unraid:~# fdisk -l /dev/sdg
Disk /dev/sdg: 14.55 TiB, 16000900661248 bytes, 31251759104 sectors
Disk model: TOSHIBA MG08ACA1
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disklabel type: gpt
Disk identifier: AC18C6E6-D4BB-4C80-86E3-75CC788100F2

Device     Start         End     Sectors  Size Type
/dev/sdg1     64 31251759070 31251759007 14.6T Linux filesystem

 

 

root@unraid:~# fdisk -l /dev/sdh
Disk /dev/sdh: 14.55 TiB, 16000900661248 bytes, 31251759104 sectors
Disk model: TOSHIBA MG08ACA1
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disklabel type: gpt
Disk identifier: 3161D52F-34A4-4043-904A-1ABC0DED666D

Device     Start         End     Sectors  Size Type
/dev/sdh1     64 31251759070 31251759007 14.6T Linux filesystem

unraid-diagnostics-20241204-2011.zip

All parity drives have to be at least as large as the largest data drive so the message was valid as at that time you still had a 4TB parity drive present.