I was attempting to connect 3 PC’s (Personal and two servers) via the TL-SG105 un-managed network switch. Beforehand i just connected one server and the personal pc into another switch i have. But i got this switch to accommodate this new server. However it seems as soon as i plugged in and turned on the new switch all of a sudden both servers no longer are able to recognize their cables. Personal PC is running linux mint, one server(the one i had before) is also running linux mint, and another server is running ubuntu 22.04.

  • Home network consists of 1 comcast gateway (modem+router combo) with two ethernet LAN ports. One ethernet LAN port is connected to a seperate switch that functions perfectly for all other devices connected to it, the other is connected to TL-SG105.

  • Personal PC can connect to internet just fine, either threw TL-SG105, or the other switch- I have attempted to plug both servers directly into the other switch and still no link.- Both servers show via ifconfig command that their respective ethernet flags indicate UP, but not RUNNING. Usually this means cable is not recognized. confirmed via ethtool command that link status is ‘NO’

  • Swapped cables between all 3 devices on TL-SG105 and confirmed all cables are operational.

  • Reset TL-SG105 multiple times during each swap of cable. And restart network manager multiple times as well as turned both servers on and off again.

Edit: I actually had to double check the switch, turns out i do have the SG105 not the SG105E. SG105E is managed, i have unmanaged.

  • GreatAlbatross
    link
    fedilink
    English
    210 months ago

    If it’s a 5 port TP link switch, it’s important to start it up connected to the upstream router on the first port.

    If it does not receive DHCP info (being assigned an IP by your router) when starting up, it will perform DHCP itself, which will cause chaos if your main router is trying to do the same.

    • @MrFoenBoxOP
      link
      110 months ago

      That would explain this chaos. But how do resolve it? Resetting the router, then both switches does not seem to improve things.