So I’m working on a server from home.
I do a cat /sys/class/net/eth0/operstate and it says unknown despite the interface being obviously up, since I’m SSH’ing into the box.
I try to explicitely set the interface up to force the status to say up with ip link set eth0 up. No joy, still unknown.
Hmm… maybe I should bring it down and back up.
So I do ip link set eth0 down and… I drive 15 miles to work to do the corresponding ip link set eth0 up
50 years using Unix and I’m still doing this… 😥
I have once actually used a console server console server to troubleshoot a misbehaving console server.
i once worked at a place that had something like this and; it sounds silly; but i got a live demonstration that it was the smartest thing ever.