Comment # 9 on bug 1188949 from Jonathan Kang

(In reply to Vladislav Milenin from comment #8)
> Created attachment 852086 [details]
> journalctl -b -u NetworkManager from a third-party repository
> 
> Yes, I noticed that I installed this package incorrectly. I installed it for
> the second time, but this time correctly. Even in the config, NetworkManager
> replaced dhcp=dhclient to dhcp=internal. I noticed a very strange behavior
> of the network. The network was connected to the Internet normally for two
> days, but this morning it refused to connect again. I had to use the phone
> as a USB modem. In the afternoon, I turned it on again and the network was
> already connected normally. The strange thing is that I noticed that if you
> connect the Internet via your phone as a USB modem, then after disconnecting
> it from the computer, the network sometimes connects correctly for some time.

The logs indicates that during the phase of DHCPDISCOVER, the ethernet link was
disconnected somehow and your system cannot get DHCPOFFER from the dhcp server.

But without the whole "journalctl -b" for the system, I'm unable to tell
exactly
why the link was disconnected and no carrier was available for the ethernet
interface. Could you please attach the output of "journalctl -b" here?