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    No link when LAN connects to Cisco Switch

    Scheduled Pinned Locked Moved General pfSense Questions
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    • B
      brb78
      last edited by brb78

      I have a router on a stick setup (ISP>pfsense>Catalyst>devices on VLANS) that's been running for ~2 years with limited interruption. The following issue has arisen before, but until now was fixed with a reboot.

      When I connect em0 (my LAN) to my Cisco Catalyst I get nothing. No lights, no link, as though its not connected at all. This is my primary switch, and has run with few interruptions prior to this issue. I've checked the cabling. all good when plugged into other devices, and when I connect em0 to a Linksys I typically use as a WAP it connects on em0 no problem. my current setup is (ISP>pfsense>Linksys>Catalyst>devices on VLANS), but this seems unnecessarily complicated.

      Any thoughts on why em0 cant seem to establish a direct link to the Catalyst it had been running directly on for years without the Linksys as an intermediary are appreciated? Any reason why, on a known good cable, it would appear as though nothing is connected on em0 when the Catalyst is connected? Yet the same cable can establish a connection to a different device, which can then be connected to the Catalyst on the same port where em0 couldn't even link?

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      • stephenw10S
        stephenw10 Netgate Administrator
        last edited by

        Can you connect em0 to any port on the switch?
        How long is the cable? Can you use something shorter?

        It sounds like a failing port at one end. Anything using em is probably quite old.

        Steve

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        • B
          brb78 @stephenw10
          last edited by

          @stephenw10 I've tried 2 of 48 with no success on the Catalyst, but em0 does connect to the Linksys no problem. Its a 12 year old Supermicro D525, so physical failure is not out of the question. Not sure why it would negotiate no problem with a 1 year old Linksys but fail to detect a 10 year old Cisco, maybe improved protocols?

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          • stephenw10S
            stephenw10 Netgate Administrator
            last edited by

            Mmm, something nearing failure I'd guess. Probably a power component somewhere. Unlikely something repairable though. Can you try a different NIC?

            Steve

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            • bingo600B
              bingo600
              last edited by

              Could it be that the Cisco Port needs mdix auto ?

              /Bingo

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              • stephenw10S
                stephenw10 Netgate Administrator
                last edited by

                Worth checking if that somehow got disabled. All Gigabit devices should be auto-MDIX though.

                You might also try linking it at 100Mb fixed as a test.

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                • B
                  brb78
                  last edited by brb78

                  I've enabled auto-MDIX and tried on a port set to 100 on the Cisco, also, 4 of 48 ports (100% of those tested) show no activity or link when connected to em0/LAN on pfsense.

                  I've also replicated similar behavior when connecting em0/LAN to a Brocade ISX6610 of similar age. Seems something about these old switches doesn't agree with em0 on my pfsense.

                  No problems when conmecting em0 to a recent Linksys router, other than not being an ideal setup.

                  A new nic should arrive today, then I'll see if that works better than the onboard for connecting to my old switches. Open to any other suggestions.

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                  • stephenw10S
                    stephenw10 Netgate Administrator
                    last edited by

                    Has em0 somehow been set to a fixed speed/duplex?

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                    • B
                      brb78 @stephenw10
                      last edited by brb78

                      @stephenw10 you may be on to something, "Speed and Duplex" are set to "default (no preference, typically auto select)" on the "Interface / LAN (em0)" tab, but my main dashboard reports "LAN 100baseTX <full-duplex>"

                      I set em0 to "autoselect", same behavior, same results.

                      I set the switch port I connect em0 on to 1000/full duplex and did the same for em0... that made em0 responsive no matter what it was plugged into (old cisco and brocade, new linksys)

                      I was able to restore my previous config and connect em0 back to the new linksys at "100baseTX <full-duplex>", and that's apparently when I stand until I can try out this new NIC - its an Intel 82576 chipset, so hopefully a smooth transition.

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                      • B
                        brb78
                        last edited by brb78

                        Installed the new NIC, LAN is set to "autoselect" and reporting "1000baseT <full-duplex>". Seems like it was bad/dying hardware.

                        Thanks for the help/suggestions.

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                        • stephenw10S
                          stephenw10 Netgate Administrator
                          last edited by

                          Ah, that sounds like it's missing some lines and the linksys can detect that and fall back to 100M, which only needs two pairs. If that is the case then setting 100M fixed at both em0 and the Cisco switch should also link. If that does work then you are losing some connections somewhere. If not the cable then it could be in the port perhaps?

                          Steve

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