What OS?

[Snooli]

So I have a QNAP NAS with 2x4TB drivevs in RAID 1, but I'm slowly running out of place and the NAS is just way too slow.

I found an HP NAS for fairly cheap, so i'll be using that for the new NAS, but I coul use some help on picking the right OS.

 

The main requierement is software RAID 5 capable of growing. The plan is to buy 2 more disks, create an array on them, copy stuff from the old NAS, and then add then add the old drives to the new array. FreeNAS is out of the picture, because ZFS doesn't allow growing, I'd have to create a new vdev, thus loose on capacity. I've also tried openmediavault, but you can't add users to admin group...

So what would be my best option?

[PeachyUwUSenpai]

don't remember what filestorage standard it uses but unraid should probably work for you i've grown it before withought any issue