Re: Network suddenly stopped working

[Reco <recoverym4n@enotuniq.net>]

	Hi.

On Mon, Jul 12, 2021 at 12:16:59PM +0200, Michael Lange wrote:

This:
> With ifconfig the enp2s0 interface appears to be up,

combined with this:
> I suspected udev to have for some reason changed the interface name;

does not add up.

If, for some reason, an interface name had changed - you won't see
"enp2s0" in the ifconfig output.


> some sources I found suggest to look at
> /etc/udev/rules.d/70-persistent-net.rules but there is nothing in that
> file that is not commented out, so I guess that this mechanism may be
> outdated.

It is outdated, and that file should not be present at all.


> The output of `systemctl status networking.service` looks like this:

In other words, it is useless. A usual thing, nothing unexpected.


Troubleshooting steps:

1) Obtain tcpdump unless it's installed already.
2) As root, run "tcpdump -pni any udp port 67 or udp port 68", and let
it run for a while.
3) As root, run "dhclient enp2s0".
4) Wait for a minute or so, terminate both tcpdump and dhclient.
5) Post the output of steps 2 and 3, plain text preferred, add an output
of "ip a" for a good measure please.

Reco