Wanted to know if I setup a RAID 6 could I change how many drives I want to use for a parity.
You can change RAID6 to RAID5, but AFAIK, you cannot add more parity drives. I think there are some pending BTRFS patches for this, but I don’t think they are merged. We don’t do any BTRFS customization at this time.
I’m new to the NAS world so that’s why I was asking. I didn’t know if there was a feature I was overlooking. Just seemed odd that you can make RAID 6 as big as you want but only have the option to loose two drives.
for zfs which is the closest to btrfs there is raidz3 which is parity on 3 disks, but for btrfs there currently is no such implementation. There are linux kernel patches to support up to six parity drives and a patch for btrfs which allows the same (here), but its pretty old, untested, but seemed to work at that time.