Sanity check on my plan to grow existing pool

[JV9]

OS: TrueNAS-13.0-U4
Motherboard: SUPERMICRO X10SDV-4C+-TLN4F-O
RAM: 32GB ECC
Case: Fractal Design Node 304
Boot / jails: Crucial P2 500GB NVMe M.2 SSD
Data: 6 x 4TB WD Red Plus (CMR)

The pool is made up of 3 vdevs, each consisting of 2 mirrored drives.

Currently 6.8TB free, 3.8TB used (36%)

I need to increase the size of the pool significantly to deal with moving my media off of google drive and back to local storage.

Would appreciate a sanity check and advice on growing the pool as follows:

1) Acquire 2 x 14TB WD Red Plus drives
2) Swap a 14TB drive for a 4TB drive in one of the vdevs
3) Allow resilvering to complete
4) Swap the other 14TB drive for the other 4TB drive in the vdev
5) Allow resilvering to complete
6) The pool will grow automatically to include the extra 10TB in the vdev

The case holds 6 drives total, so I'd be replacing these one at a time and allowing the resilvering.

Can I do the whole process via the GUI or will I need the CLI?

 

[Whattteva]

That sounds about right and you should be able to do it via the GUI. You may want to offline the drive first before swapping it.

 

[JV9]

That sounds about right and you should be able to do it via the GUI. You may want to offline the drive first before swapping it.

Thank you!