Nic interface and cable problem

  • Hi,

    I just added to my pfsense machine a new interface Allied Telesis with 1000mbps, i also have a lan and a wan with 100mbps, i added the 1000mbps interface because i want to have with one of the clients a 1000mbps connection.So far that client has been connected on lan through a switch, connection worked fine but with 100mbps because lan is 100mbps interface.Also that client has a 1gbps card interface for sure.
      The added interface is working 100% as device…has been added and dhcp enable but when cable from client is inserted direct in it i go cable unplugged…and i'm not sure why ? i want to make a remark my cable from client to interface is only with 4 wire not with 8 but with initial lan it's working great at 100mbps...but when connection is made direct from client to added interface i got network is not inserted.Also i tryed to see added interface is working with a short standard cable and is working.


  • @bmironb:

    i want to make a remark my cable from client to interface is only with 4 wire not with 8

    If I recall correctly Gigabit Ethernet over copper REQUIRES an 8 wire cable. I believe over short distances (a metre or two) a Cat5E cable might work but Cat6 cable should be used for best results.

  • Netgate Administrator

    Yes Gigabit requires all 8 wires. The most you can get with 4 wires is 100Mbps.
    But it's worse than that! Gigabit uses only 4 wires to negotiate the connection speed and type. Since you have gigabit NICs at each end it is negotiating to 1000Mbps full duplex but then can't connect because the other 4 wires are missing. Result - no connection at all.  :(

    Some NICs/drivers have code to make sure that doesn't happen but not all.


  • Ok guys thanks a lot ! i will change the cable
    I'm wondering if it will be some improvments if that client that will be connected with 1gbps at pfsense machine will have improvments…network time...I nottice another thing that now when client for example is downloading something and is trying to enter in pfsense dashboard is entering a little bit harder...because of network utilization...this thing i think that will be changed ? by wiring it direct to pfsense and at 1gbps speed.


  • Netgate Administrator

    It will only help if your other interface is close to maximum bandwidth. Even then it probably won't make much difference.
    By separating the clients you are then routing any traffic between clients through your pfSense box. This will be slower than via the switch. This may be a significant problem if you transfer a lot of data that way.


  • Yes but i'm interested of traffic from wan -> that interface, traffic from internet, but then when traffic is made between that client on 1gbps interface and others on switch i will have pfsense sistem utilization ? cpu…maybe is not such a good idea.

  • Netgate Administrator

    Try it and see. You should be able to get your other connection working without replacing the cable by setting both ends to 100Mbps full duplex.


Log in to reply