Creating a RaidZ1 pool with different size disks

TrueNAS General
,
1

Hi,
I have three 4TB and two 6TB NAS disks laying around and decided to create a Truenas Community Edition Scale V 25.
My goal is to create two RAIDZ1 VDEVs with three disks each and stripe them. Can I stripe two VDEVs with different capacities?
Would the smallest disk size determine the total capacity of each VDEV? In other words, if I create two VEDVs with 4TB and 6TB triplets, would Truenas treat these as if they are all 4TB drives or use the extra capacity of the bigger 6TB disks?
Thanks.

2

If you create a RaidZ1 vdev with three 4TB drives, that vdev will have a capacity of 8TB

If you create a RaidZ1 vdev with three 6TB drives, that vdev will have a capacity of 12TB.

If you add both vdev to a storage pool that pool will have 20TB storage.

All (data) vdevs in a pool are striped. Redundancy only exists within the vdev, not at the pool level.

You will need a third 6TB disk though.

1 Like
5

Thank you Krill.
My primary concern was whether it was technically possible to use differently sized vdevs within a pool. I am aware of the third 6TB disk situation. BTW I have found the pool creation wizard to be bit confusing for the newcomers. I am telling this as a long time Freenas/Truenas Core user.
Thanks again.

6

Agreed. But you can skip the wizard and create your vdevs manually.