This problem started on Ubuntu 22.04 about a year ago and is also present on Ubuntu 24.04 which was cleanly installed on the same PC. Computer is connected by ethernet cable to a home router, some Zyxel given to me by the ISP.
Most times, everything works without any problems. But sometimes on boot Ubuntu won't connect. And here is the strange part: in order to make it work, you have to wait for notification to show that the network connection is not available, close that notification, then unplug the network cable from the router and plug it in another ethernet port on the router. If you change the port before the notification is shown or do not close the notification first, changing the port does not fix the issue. Rebooting the computer or the router often doesn't fix the issue either, only the mentioned workaround is reliable.
I've checked journal messages when this happens and I can't seem to find the problem. My guess is that lower and higher level network tools and systems are possibly quarreling among themselves. Any ideas what could be the problem or what I could check?
Most times, everything works without any problems. But sometimes on boot Ubuntu won't connect. And here is the strange part: in order to make it work, you have to wait for notification to show that the network connection is not available, close that notification, then unplug the network cable from the router and plug it in another ethernet port on the router. If you change the port before the notification is shown or do not close the notification first, changing the port does not fix the issue. Rebooting the computer or the router often doesn't fix the issue either, only the mentioned workaround is reliable.
I've checked journal messages when this happens and I can't seem to find the problem. My guess is that lower and higher level network tools and systems are possibly quarreling among themselves. Any ideas what could be the problem or what I could check?