How to rename a ZFS Volume on FreeNas

What you basically need to do is export the zpool using the shell command line (not on the web interface).

The commands a fairly simple.

zpool export [current zpool name here]

zpool import [current zpool name here][space here][new zpool name here]


zpool export volume0

zpool import volume0 volume1

Keep in mind that afterwards, at least I had to do it, to detach the volumes (zpools) from the system (DON’T CHECK THE OPTION TO ERASE DATA).

Auto-import volumes (zpools).
And bingo you have the volumes back with the new names and all of your data kept intact! 

More Information [Detailed]: [Detach Volume Section]