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