[1.9,2.0,UX] Can't add aliases when parent interface is set to 'DCHP'

[Jacek Nykis]

I'm trying to model the following network setup:
bond0 - main interface set to DHCP
bond0:1 - alias with statically assigned IPv6 address

This does not seem possible

When I switch bond0 from "Static assign" to DHCP the "+" sign to add aliases disappears. When I switch back to "Static assign" the plus sign appears again and I can add aliases.

I also tried to set bond0 to static, add alias and then switch bond0 to "DHCP" but when I add one alias I can no longer edit bond0 settings.

Desired=Unknown/Install/Remove/Purge/Hold
| Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend
|/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad)
||/ Name Version Architecture Description
+++-===========================================================-=============================================-============-===============================================================================
un maas <none> <none> (no description available)
ii maas-cli 1.9.3+bzr4577-0ubuntu1~trusty1 all MAAS command line API tool
un maas-cluster-controller <none> <none> (no description available)
ii maas-common 1.9.3+bzr4577-0ubuntu1~trusty1 all MAAS server common files
un maas-dhcp <none> <none> (no description available)
ii maas-dns 1.9.3+bzr4577-0ubuntu1~trusty1 all MAAS DNS server
ii maas-proxy 1.9.3+bzr4577-0ubuntu1~trusty1 all MAAS Caching Proxy
ii maas-region-controller 1.9.3+bzr4577-0ubuntu1~trusty1 all MAAS server complete region controller
ii maas-region-controller-min 1.9.3+bzr4577-0ubuntu1~trusty1 all MAAS Server minimum region controller
ii python-django-maas 1.9.3+bzr4577-0ubuntu1~trusty1 all MAAS server Django web framework
ii python-maas-client 1.9.3+bzr4577-0ubuntu1~trusty1 all MAAS python API client
ii python-maas-provisioningserver 1.9.3+bzr4577-0ubuntu1~trusty1 all MAAS server provisioning libraries

Logs (please don't share outside of the company):
https://private-fileshare.canonical.com/~jacek/1600267.tgz

[Mike Pontillo (mpontillo)]

Note that this is just a UI issue. The model allows this; you can do something like this via the API:

maas admin interface link-subnet hn4sr6 46 mode=static subnet=2001:db8::/64