Netgate Discussion Forum
    • Categories
    • Recent
    • Tags
    • Popular
    • Users
    • Search
    • Register
    • Login

    WAN Interface only gets DHCP if speed manually set?

    Scheduled Pinned Locked Moved 2.1 Snapshot Feedback and Problems - RETIRED
    15 Posts 7 Posters 4.4k Views
    Loading More Posts
    • Oldest to Newest
    • Newest to Oldest
    • Most Votes
    Reply
    • Reply as topic
    Log in to reply
    This topic has been deleted. Only users with topic management privileges can see it.
    • E
      Eurisko
      last edited by

      It auto negotiated to Gig, and by the time I logged into the system, it had a correctly assigned DHCP IPV4 address. However, I don't know if Windows "keeps trying" if it doesn't get it the first time around. I think PFSense tries just the one time.

      1 Reply Last reply Reply Quote 0
      • N
        NOYB
        last edited by

        I've seen this same behavior before on a Microsoft Virtual PC VM.  If I recall I was able to do an interface down/up (ifconfig) and then it would get an address.  I know that doesn't solve the problem but perhaps a clue toward the root cause if that works in your case too.

        1 Reply Last reply Reply Quote 0
        • C
          cmb
          last edited by

          @Eurisko:

          It auto negotiated to Gig

          My guess is you were using a different cable with the Windows box. Probably now using a CAT5 cable, not CAT5e, which should just negotiate fine to 100 Mb but maybe either the NIC you have or your cable modem doesn't play nicely with autonegotiation when it can't negotiate to gigabit.

          @Eurisko:

          and by the time I logged into the system, it had a correctly assigned DHCP IPV4 address. However, I don't know if Windows "keeps trying" if it doesn't get it the first time around. I think PFSense tries just the one time.

          No, it'll try indefinitely, the same as Windows and every other DHCP client, it'll keep trying forever until it gets a lease.

          1 Reply Last reply Reply Quote 0
          • B
            bkraptor
            last edited by

            I can confirm that running the same hardware (Intel D2500CCE with an added two-port Intel Gigabit card for WAN) and a Huawei HG655b xDSL modem in bridge mode I do not get any DHCP replies unless I manually set my speed to 100 Mbps full duplex. I always thought this was an issue with the modem's speed negociation, but this thread makes me think otherwise.

            1 Reply Last reply Reply Quote 0
            • R
              rjcrowder
              last edited by

              @bkraptor:

              I can confirm that running the same hardware (Intel D2500CCE with an added two-port Intel Gigabit card for WAN) and a Huawei HG655b xDSL modem in bridge mode I do not get any DHCP replies unless I manually set my speed to 100 Mbps full duplex. I always thought this was an issue with the modem's speed negociation, but this thread makes me think otherwise.

              I had this same problem - it was the cable…

              1 Reply Last reply Reply Quote 0
              • johnpozJ
                johnpoz LAYER 8 Global Moderator
                last edited by

                "the same as Windows and every other DHCP client, it'll keep trying forever until it gets a lease. "

                Not sure I would state it like that for windows - with "windows" the dhcp client will at some point it will just assign its own random 169.254 address (APIPA) This feature can be turned off.  But is on by default.

                So according to this
                http://support.microsoft.com/kb/220874

                Depending if the interface had a previous address, or lease expires then the timing changes.  But yes it does continue to send out dhcp discover either every 3 minutes or every 5 minutes depending even after its assigned itself a 169.254 address.  It looks like it will send out atleast 3 discover if has never had a lease.  But they also state "more" so its not real clear on exact number of discover it will send our how fast it sends them, etc.  Before it does APIPA and then resorts to sending at a timed interval a discover.

                An intelligent man is sometimes forced to be drunk to spend time with his fools
                If you get confused: Listen to the Music Play
                Please don't Chat/PM me for help, unless mod related
                SG-4860 24.11 | Lab VMs 2.8, 24.11

                1 Reply Last reply Reply Quote 0
                • W
                  wallabybob
                  last edited by

                  @cmb:

                  No, it'll try indefinitely, the same as Windows and every other DHCP client, it'll keep trying forever until it gets a lease.

                  On at least some versions of Ubuntu the DHCP client gave up after some time.

                  1 Reply Last reply Reply Quote 0
                  • N
                    NOYB
                    last edited by

                    @bkraptor:

                    I can confirm that running the same hardware (Intel D2500CCE with an added two-port Intel Gigabit card for WAN) and a Huawei HG655b xDSL modem in bridge mode I do not get any DHCP replies unless I manually set my speed to 100 Mbps full duplex. I always thought this was an issue with the modem's speed negociation, but this thread makes me think otherwise.

                    Can you do network capture to see if pfSense is making DHCP request.  In my MS-VPC instance it was not.

                    Don't just assume the DHCP request is actually being made.

                    1 Reply Last reply Reply Quote 0
                    • johnpozJ
                      johnpoz LAYER 8 Global Moderator
                      last edited by

                      I don't believe dhcp client is going to make a request until the interface is up, interface is not up if can not neg what speed or duplex it should be connected at.

                      This is why he needs to troubleshoot his autoneg - chicken/egg thing, you can't have dhcp working if you don't have a working inteface.  How do you have a working interface if no speed or duplex worked out, etc.

                      An intelligent man is sometimes forced to be drunk to spend time with his fools
                      If you get confused: Listen to the Music Play
                      Please don't Chat/PM me for help, unless mod related
                      SG-4860 24.11 | Lab VMs 2.8, 24.11

                      1 Reply Last reply Reply Quote 0
                      • E
                        Eurisko
                        last edited by

                        I hate to admit it, but it was the cable!

                        I had already swapped the cable out once before, but obviously I have some inferior cables laying around. Nice new CAT5e cable, and it works perfectly.

                        Thanks!

                        1 Reply Last reply Reply Quote 0
                        • johnpozJ
                          johnpoz LAYER 8 Global Moderator
                          last edited by

                          Great to hear..  Its not very common, but yes sometimes the wire is not quite right..

                          An intelligent man is sometimes forced to be drunk to spend time with his fools
                          If you get confused: Listen to the Music Play
                          Please don't Chat/PM me for help, unless mod related
                          SG-4860 24.11 | Lab VMs 2.8, 24.11

                          1 Reply Last reply Reply Quote 0
                          • First post
                            Last post
                          Copyright 2025 Rubicon Communications LLC (Netgate). All rights reserved.