XigmaNAS

Hi,
I decided to go from 2 RaidZ1 pools to a single mirrored Pool, so I backed up all my data, destroyed the original pool and build a new pool.
When I created the pool in the GUI and attempted to apply changes I kept getting "Error: The changes could not be applied (error code 1)."
So I went ahead and created the pool in the CLI

I have 14 2TB drives so the pool has 7 mirrors so I expect to see 14TB storage available, however I am only seeing 12. what Am I doing wrong, should I start over and re-install from scratch? Thanks for your help

NAME STATE READ WRITE CKSUM
tank ONLINE 0 0 0
mirror-0 ONLINE 0 0 0
ada1 ONLINE 0 0 0
ada4 ONLINE 0 0 0
mirror-1 ONLINE 0 0 0
ada7 ONLINE 0 0 0
ada8 ONLINE 0 0 0
mirror-2 ONLINE 0 0 0
ada9 ONLINE 0 0 0
ada10 ONLINE 0 0 0
mirror-3 ONLINE 0 0 0
ada12 ONLINE 0 0 0
ada13 ONLINE 0 0 0
mirror-4 ONLINE 0 0 0
ada6 ONLINE 0 0 0
ada11 ONLINE 0 0 0
mirror-5 ONLINE 0 0 0
ada5 ONLINE 0 0 0
ada2 ONLINE 0 0 0
mirror-6 ONLINE 0 0 0
ada0 ONLINE 0 0 0
ada3 ONLINE 0 0 0

errors: No known data errors
frankennas: ~# zfs list
NAME USED AVAIL REFER MOUNTPOINT
tank 300K 12.3T 96K /mnt/tank

frankennas: ~# df
Filesystem 1K-blocks Used Avail Capacity Mounted on
/dev/xmd0 122606 83206 39400 68% /
devfs 1 1 0 100% /dev
/dev/xmd1 736430 420292 316138 57% /usr/local
procfs 4 4 0 100% /proc
/dev/xmd2 507420 4624 462204 1% /var
tmpfs 262144 52 262092 0% /var/tmp
tank 13197377332 96 13197377236 0% /mnt/tank
/dev/da0p2 761134 189734 571400 25% /cf

From my system
You can se that the 2G drive only has 1.8 Tbyes. The difference is main due to disk drive maths. (to convert HDD Byes to TB divide 1024x1024)

There is also some space reserved for ZFS - I think about 1/64 of the space.

That brings you to in the ball park of what you are seeing