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    DHCP IP Range does not change - when changing LAN IP

    Scheduled Pinned Locked Moved 2.0-RC Snapshot Feedback and Problems - RETIRED
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    • R
      root2020
      last edited by

      All,

      I think that I have seen this before, but I would like to mention it again to make sure. I was working on 2 pfsense RC-1 boxes last weekend. When I changed the local LAN IP, the DHCP server kept handing out the original 192.168.x.x instead of the new 172.x.x.x that I setup. I have verified it works 1.2.3 works just fine when you change the IP address. Anyone else having a similar issue?

      P.S. PfSense Rocks!

      Rhett

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      • W
        wallabybob
        last edited by

        @root2020:

        When I changed the local LAN IP, the DHCP server kept handing out the original 192.168.x.x instead of the new 172.x.x.x that I setup.

        Did you change the DHCP server's address range to 172.x.x.x?

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        • R
          root2020
          last edited by

          Yes, when I found out what was wrong. I am just used to pfsense 1.2.3 and all other firewalls that change the range, when you change the LAN IP. I am just saying that I know how to fix the issues, but newcomers might frown on this.

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          • W
            wallabybob
            last edited by

            @root2020:

            I am just used to pfsense 1.2.3 and all other firewalls that change the range, when you change the LAN IP.

            I'm surprised that some firewalls apparently automatically know what IP address range the DHCP server should be assigned when the IP address of an interface is changed to a different subnet.

            @root2020:

            I am just saying that I know how to fix the issues, but newcomers might frown on this.

            It is helpful that you reported unexpected behaviour. It would be even more helpful if you also reported what you did to "work around" the unexpected behaviour.

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            • ?
              Guest
              last edited by

              you get a warning telling you to update your DHCP before the changes are applied. Read warnings before applying an action and you'll be in the clear :-)

              dhcp.PNG
              dhcp.PNG_thumb

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              • S
                sidhupf
                last edited by

                DHCP range change does not take BEFORE applying the LAN IP change. Never get the chance to change DHCP range after applying cuz the system becomes unresponsive. Also tried disabling DHCP which changing LAN IP - same unresponsiveness. Have NOT been able to find a solution to this.

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                • S
                  sidhupf
                  last edited by

                  BTW, the warning says make the DHCP changes AFTER applying the LAN IP change.

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                  • R
                    root2020
                    last edited by

                    Good point, guess I was just click happy

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                    • A
                      Alan87i
                      last edited by

                      @sidhupf:

                      DHCP range change does not take BEFORE applying the LAN IP change. Never get the chance to change DHCP range after applying cuz the system becomes unresponsive. Also tried disabling DHCP which changing LAN IP - same unresponsiveness. Have NOT been able to find a solution to this.

                      Have you tried it from an ssh console or using a screen and keyboard on the router it's self?

                      Seems I did this 2 months ago with direct input sitting beside the router and it worked fine.

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                      • ?
                        Guest
                        last edited by

                        Assign yourself a static IP matching the new LAN subnet or make the change to DHCP @ console. It's maybe a lack of convenience but you're informed to update the DHCP, they probably expect you to know that traffic will not get routed to a different subnet without a gateway. (If you change the LAN IP to 192.168.0.1/24, and you're still using the previous subnet (say 192.168.1.1/24), then you'll make requests to a gateway (because you're trying to send traffic on a different subnet) that no longer exists and your traffic goes nowhere.

                        @sidhupf:

                        DHCP range change does not take BEFORE applying the LAN IP change. Never get the chance to change DHCP range after applying cuz the system becomes unresponsive. Also tried disabling DHCP which changing LAN IP - same unresponsiveness. Have NOT been able to find a solution to this.

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