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    DHCP relay no longer working after 2.2.4 -> 2.2.5 (Sun Oct 04 09:39:48 CDT)

    Scheduled Pinned Locked Moved 2.2.5 Snapshot Feedback and Issues
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    • G
      gerdesj
      last edited by

      After updating to 2.2.5 SNAPs my DHCP relay stopped working on all VLANs.  The config was there and the service was running and a packet capture on the DHCP server itself showed requests coming in and replies going out OK.  Clients were not getting a response.  I didn't get a chance to run Wireshark on a client PC to see if anything was coming back to the client.  I did run Packet Capture on the pfSense box but stupidly on the DHCP server side and not the client side.

      I had to rather quickly learn "3Com badged as HP"-ese on the nearest L3 switch to get things running again and haven't had a chance to look closer to see where it breaks down.

      (Edit) Sorry forgot to mention - amd64 full install on VMware 5.5, with guest tools and OpenVPN export packages and nothing else.

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      • C
        cmb
        last edited by

        Are both your clients and the DHCP server residing on VLANs?

        What output do you get running:

        ps auwwx|grep dhcrelay
        
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        • G
          gerdesj
          last edited by

          @cmb:

          Are both your clients and the DHCP server residing on VLANs?

          What output do you get running:

          ps auwwx|grep dhcrelay
          

          cmb

          Thanks for responding.  I have had to deal with other issues today - a dodgy WAN connection.  On the bright side I am now heavily testing IPSEC VPN failover via dynamic DNS and then I've got OpenVPN to do.  There aren't many features left in pfSense that I don't touch!

          The DHCP server (Windows 2012R2) is on the server VLAN whilst clients, phones, etc etc each have their own VLANs.  All are routed via pfSense.  To be honest pfSense in a VM makes a damn fine switch! I am getting near wire speed routing/switching with not the fastest hardware.

          I have not revisited the dhcp relay in pfSense yet but I was able to see via Wireshark on the DHCP server that requests were arriving and responses were going back out again.  I had to get things running again so I learnt 3Com and got a L3 switch to do the job for now.

          I will hopefully be able to spin up a new VLAN tomorrow (BST/GMT+1) for testing and make pfSense relay for that one.  I can then leisurely trace the whole process and look for malformed options or whatever.

          Again, thanks for coming back and I'll post results as soon as possible.

          Cheers
          Jon

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          • G
            gerdesj
            last edited by

            @cmb:

            Are both your clients and the DHCP server residing on VLANs?

            What output do you get running:

            ps auwwx|grep dhcrelay
            

            DHCP server is on VLAN 14 - 10.77.14.14
            PC is on VLAN 13 (10.77.13.0/24)

            Output from ps:

            
            root    2597   0.0  0.5  20184   9868  -  Is    5:15PM   0:00.00 /usr/local/sbin/dhcrelay -i em1_vlan13 10.77.14.14
            
            

            Wireshark on the DHCP server shows a request arriving from 10.77.13.1 (pfSense's IP on the PC's VLAN). I can see this in the offer:

            
            ...
            Your (client) IP address: 10.77.13.130 (10.77.13.130)
            ...
            Relay agent IP address: 10.77.13.1 (10.77.13.1)
            ...
            
            

            … but nothing gets back to the client.

            Cheers
            Jon

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            • C
              cmb
              last edited by

              I fixed an unrelated bug that irked me during testing.

              And I reverted the cause of the problem here. Despite claims to the contrary from some who reported it as a problem, and dhcrelay's documentation seemingly making that correct, it is necessary for it to function.

              Should work now.

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              • D
                doktornotor Banned
                last edited by

                @cmb:

                I fixed an unrelated bug that irked me during testing.

                Thanks… :) BTW, I think you have one = missing there.

                if ($dhcrelayif = $on) {
                
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                • G
                  gerdesj
                  last edited by

                  @cmb:

                  I fixed an unrelated bug that irked me during testing.

                  And I reverted the cause of the problem here. Despite claims to the contrary from some who reported it as a problem, and dhcrelay's documentation seemingly making that correct, it is necessary for it to function.

                  Should work now.

                  Thank you.  I'll give it a go in the near(ish) future.

                  Cheers
                  Jon

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                  • C
                    cmb
                    last edited by

                    @doktornotor:

                    Thanks… :) BTW, I think you have one = missing there.

                    if ($dhcrelayif = $on) {
                    

                    Fixed that too, thanks.

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                    • D
                      doktornotor Banned
                      last edited by

                      Thanks; will test some new snapshot this weekend.

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