single ethernet connection is cloned to two connections

[luca.mina]

Hi,
I have debian jessie with network manager to manage my single ethernet card. Sometimes the connection is cloned, I mean instead of one connection network manager shows two connections, one of them does not work. When it happen internet does not automatically connects to the good one, even if I correctly checked to do inside network preferences and to not do it to the bad one.
Inside network preferences both connections share the same MAC address but the bad one also show "cloned address" with the hardware address of the good one.

• "ifconfig -a" shows eth1 and lo, there is no eth0 (?)
  
  /etc/network/interfaces is blank regarding eth1, so everything is leaved to network manager
  
  "service network-manager restart" do not fix it, but rebooting will do

Someone has any idea?

Thanks
Luca

[bw123]

You can use nmcli from terminal to get more info, and paste into code tags here, after removing any info you don't want to share. Maybe something will make sense about what's going on. What happened when you deleted the 'bad' or cloned connection, did it come back? I think nm should automatically create a connection for wired device, but this can be changed.

These commands work for me as a regular user on jessie, not sure this will work on stretch.

Code: Select all

$ man nmcli
$ nmcli connection show
$ nmcli device show