Hi,

sometimes the root password that was set is being lost. This happened several times for me already and right now it happened after editing network interfaces.
It's not related to 2.2.2 but we're running 2.2.2 right now. I remember similar issues back in 1.x.
That's annoying esp. if that happens more often, on multiple hosts that you edit.

So in this case:
Edit a host, existing one with a root password being set
change the MAC address
enter the new IP (another issue I'll file)
save network changes
save host
You'll have to set the root password again - "should be 8 characters or more and should not be blank - consider setting a global or host group default"