[K12OSN] Users can't login

[Burke Almquist]

Two things worth noting.
One, I've found sometimes that disabling IPv6 helps.
I was always told that 127.0.0.1 should only be localhost, and never the actual machine name; that is reserved for an addressable IP.


I don't think the two things above account for your trouble though.
Exactly how is your network set up? It sounds like you are trying to do this with only one NIC. There are instructions on the wiki about this, but it's definitely more complex that just using a second NIC. Network Manager should not have control over the interface that is bridged.
Did you create virtual NICs out of your one NIC?