Lots to reply to here, so I'm going to just give the cliff notes and keep it brief ;)
1 - Jailed datasets are *exclusive* to the jail. So changing their mountpoint inside the jail is going to reflect in zfs list. That is how the process works.
2 - DHCP isn't ported to the rewrite yet, that's a Soon™ feature. The docs you linked to from FreeBSD's site are for the old version, and the iocage.readthedocs.io are also for the legacy implementation. Only so much time in a day ;) So in the meantime use the manpage included in FreeNAS (partially out of date, I know I suck at documenting :() or use
Code:
iocage COMMAND --help
3 - NullFS is definitely how you want to approach this, and good news! I have your back. iocage includes an easy command for this,
and in the case of adding a nullfs mount, just issue
Code:
iocage fstab -a JAIL /the/directory/to/share
4 - iocage has no temporary files. Changing the mountpoint of
is fine, and if iocage is having any trouble seeing them, I suggest trying
and trying again. But to avoid unexpected headaches, I'd leave it at default. Default is good, default is your friend.
I hope this clears up some stuff guys, thanks for trying iocage out! If you want a more immediate answer, use the github at
https://github.com/iocage/iocage, watching the forums is not my strength!