Setup Question - Adding Parity

[Justin6o4]

Hello!

About to build my next NAS, wanted to confirm a question here prior to setting up.

Confirming I can create a pool with 2 drives with no parity to transfer data from old NAS over.  Then take the 4 drives out of the old setup over to the new HexOS build, and setup the parity onto the pool at that time without compromising the backup data on the 2 drives i setup originally?  Just want to ensure adding the extra drives and parity to the pool will not compromise the data?

Thank you!

[PsychoWards]

Hey, no this will not work as you've described it. 

With 2 drives Hexos will automatically create a mirrored pool, meaning your data will be stored on both drives at the same time and you will only have the capacity of 1 drive but you can lose 1 drive without losing data. You cannot create a Pool without parity with more then 1 drive.

A RaidZ Pool type cannot be changed after it was created, so you will be stuck with your mirrored pool and you cannot expand it. 

If you then throw in your 4 drives from the old NAS, Hexos will create a new RaidZ1 pool, which has the capacity of the numbers of drives -1 (capacity of 3 drives in your case). You can then copy the data from your mirrored pool to your RaidZ1 pool.

If however, your mirrored pool does not have enough capacity, get yourself a 3. drive to create a RaidZ1 from the beginning, copy your data over and afterwards add your drives from your NAS to the pool or create a new pool. (expanding a pool can only be done with 1 drive at a time and takes some time).

Also make sure all your drives have the same capacity or else Hexos will not group them together. 

[Justin6o4]

Damn, well thanks for the info!

I did now also Google that HexOS "may" support the mixed capacity drives sometime in early 2026?  Being that my drives also arent all of the same size is there a benefit to holding off the switch over until that support?

I can look to purchase another 2 drives that match my 2 new ones to parity with 2 backups (goal is 2/8 being used as parity) and 2 storage drives, until this feature is added for me to slowly add in the other drives to expand the pool 1 drive at a time?

[Mobius]

2 hours ago, Justin6o4 said:

HexOS "may" support the mixed capacity drives sometime in early 2026

There is no announced timeframe at this time.

2 hours ago, Justin6o4 said:

is there a benefit to holding off the switch over until that support?

The benefit is being able to make bigger pools.