Just the same as described in my first post happened again tonight: Suddenly (like after approx. 100 of running normal) the connections on eth0 tpo the IP's behind the switch get lost. I can ping the switch, but not the other IP's connected to that switch. There is nothing in /var/log/messages (except the camera software that complains for not being able to connect with the cameras). Networkmanager shows "connected". Disconnect-reconnect/unplugg-replug cables/rebooting/completely disconnect/reconnect PC, switch and cameras from electricity doesn't help. BUT: plugging the the switch to my laptop all IP's are available on the laptop immediately, then plugging back the cable to the PC they appear there as well... I cannot explain to myself why when I connect the switch to my laptop and then back to the PC it works again immediately, but I can't re-establish eth0 connection by any other means. What does my laptop do to do the magic? My laptop isn't connected to the PC in any way (no WiFi, no eth-connection), so it can't change something on the PC. To me it seems that it changes something on the switch, but what and how? Any ideas how I can find the error? Am 02.07.23 um 14:06 schrieb Daniel Bauer:
I have some cameras connected with eth-cables to a switch and from there to a computer (OS 15.5, using zoneminder for the cameras). It works.
But this morning I saw that tonight the connection to the cameras was lost. I could ping the switch, but not the cameras. "arp -a" showed the IP's of the cameras but with "[IP] at incomplete ...".
I checked all cables. I rebooted. I switched off/on electricity for computer/switch/cameras. I unplugged the switch's cable to the computer and plugged it again.
No change.
I plugged the eth cable to my laptop (that I used before for this task, using OS 15.3) and all connections worked...
Plugged back the eth cable to the computer - and the connections work again, all cameras pingable and visible. Magic.
There are no messages in var/log, only the zoneminder-log said "no connection to..."
What happened here?
-- Daniel Bauer photographer Basel Málaga https://www.patreon.com/danielbauer https://www.daniel-bauer.com