Created attachment 201549 [details]
dmesg from 11.2
After upgrade from 11.2 to 12.0 my network stop to work. Network cards get addresses but data exchange does not occur. I tried a clean install, but the situation has not changed.
I have only 11.2 dmseg, because had to rollback quickly.
Unfortunately, there isn't really anything to go on here. I don't see any network-related error messages in the attached dmesg, so whatever issue you're encountering on 12 doesn't seem to exist on 11.2.
You might want to try using HEAD (like a snapshot that's post 1/30), since there have been a couple fixes to the em driver in the past couple days.