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    DHCP server woes

    Scheduled Pinned Locked Moved DHCP and DNS
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    • T Offline
      tucansam
      last edited by

      2.3.2 Release.  Everything was working up until last night, all I did change-wise was add a few static IP mappings to the DHCP server.

      Many of my DHCP-driven devices are getting an address outside the assigned range, specifically, several devices are getting addresses that are specifically mapped to other devices, creating an IP address conflict.  Even when only one device is powered on (ie, to remove the conflict), that devices connects to the network, gets an address, but then cannot access the internet.

      I'm at a loss here.  I've never had any issues before.  I am 100% certain there are no rogue DHCP servers on the network (small home network).

      Any advice would be great.

      Thanks.

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      • johnpozJ Offline
        johnpoz LAYER 8 Global Moderator
        last edited by

        As to getting outside pool.. Yeah that is how your reservations would work..Since you stated you creates static mappings.

        As to mapped to other devices..  Yeah that seems unlikely.

        What does your dhcp log show?  A sniff on pfsense diag, packet capture for port 67 will log all your dhcp traffic.  Now open that in wireshark - or post it here and we can take a look to what is happening..

        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 25.07.1 | Lab VMs 2.8.1, 25.07.1

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        • T Offline
          tucansam
          last edited by

          Let me explain a little better and see if this help.

          I have a few clients with static IP addresses, and a few clients that are assigned via DHCP (wireless devices) that are statically mapped to always get the same address, based on MAC address.  Then, I have a pool set aside for other clients (guests, again this is a home network, or random computers that I bring up from time to time for testing).

          Let's say PC 1 is 10.0.0.2, PC 2 is 10.0.0.3, and Laptop 1 is 10.0.0.4.  And let's say my address pool for hosts pfsense doesn't recognize is 10.0.0.50-60.

          Well, pfsense likes to assign Laptop 1 as 10.0.0.5.  Which is reserved for another host via MAC static mapping, and is also outside the pool for unrecognized hosts.

          Having said that, if the host that is typically 10.0.0.5 is turned off, ie, there is no IP address conflict when pfsense gives that address to Laptop 1, Laptop 1 can't access the internet, or ping pfsense.  But it can ping other hosts on the network.

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          • C Offline
            captainjackla
            last edited by

            First thing I would do is check the IP pool numbers.  Maybe it starts at '5' instead of '50' ?  Just checking.

            Maybe change your Pool to say "70-80".

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            • johnpozJ Offline
              johnpoz LAYER 8 Global Moderator
              last edited by

              I you have a machine set static to .5 and a reservation for some other machine for .5 as well..  Then yeah your going to have issues.

              While dhcp servers can try and see if an IP is in use, via ping - if there is a lease for something and it asks for it - it normally will get it.

              If your devices are not getting their reservations then you have the mac wrong, or there is a different dhcp server or they have another lease they are renewing.

              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 25.07.1 | Lab VMs 2.8.1, 25.07.1

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              • GertjanG Offline
                Gertjan
                last edited by

                … and as usual, the DHCP server log will show what MAC pfSense is receiving - if it's in the "static lease map", the related IP will be proposed, otherwise one of the pool will be taken.

                No "help me" PM's please. Use the forum, the community will thank you.
                Edit : and where are the logs ??

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