I had the same problem in Gentoo linux. I am by no means a network expert. I had this warning in NM log.
<warn> error in connection /etc/NetworkManager/system-connections/.keep_net-misc_networkmanager-0: invalid connection: connection.type: property is missing So I removed the the following file /etc/NetworkManager/system-connections/.keep_net-misc_networkmanager-0 I also had this file /etc/NetworkManager/system-connections/eth0 with this content: [ethernet] mac-address=10:C3:7B:AC:3B:23 [connection] id=Wired uuid=593aa2f2-5673-401a-823b-519d68e4dde2 type=ethernet [ipv6] method=ignore [ipv4] method=auto may-fail=false So I changed its name to "Wired" as it was the id. The r8169 kernel module was also buggy in my case so that it could not get an IP address when I was working in my workplace. So I switched to r8168 module. Everything looks OK now. I hope this info help you also. -- Sincerely, Keivan
