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    Dhclient[18753]: DHCPREQUEST on re0 to 10.244.64.1 port 67

    Scheduled Pinned Locked Moved General pfSense Questions
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    • M
      mevans336
      last edited by

      Hello Guys,

      I recently added a Road Runner cable modem as a backup connection, connected to a RealTek card (re0) in my pfSense 2.0.1 box.

      I've noticed that although the connection is operating normally, I keep seeing the following in the system logs:

      dhclient[18753]: DHCPREQUEST on re0 to 10.244.64.1 port 67

      I believe 10.244.64.1 is the CMTS system.

      I'm assuming it's benign, is there any way to filter it?

      Thanks,

      Matt

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      • chpalmerC
        chpalmer
        last edited by

        I believe 10.244.64.1 is the CMTS system.

        Correct

        assuming your cable connection= WAN

        On your WAN firewall rules make a rule blocking that address and put it at the top of the other rules.

        10.244.64.1 is not private space.  if it was you would also need to uncheck "Block private networks" on your WAN interface…

        Triggering snowflakes one by one..
        Intel(R) Core(TM) i5-4590T CPU @ 2.00GHz on an M400 WG box.

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        • stephenw10S
          stephenw10 Netgate Administrator
          last edited by

          Erm…
          Isn't that just the pfsense dhcp client renewing it's lease? If you block it that would be a problem.
          Presumably it appears at regular intervals.
          Am I missing something obvious.

          Steve

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          • chpalmerC
            chpalmer
            last edited by

            Blocking it wont keep the client from contacting initiating the connection.  Just stops outside from getting in and logging..

            Others such as myself do this with our cable connections with no issues…

            Triggering snowflakes one by one..
            Intel(R) Core(TM) i5-4590T CPU @ 2.00GHz on an M400 WG box.

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            • stephenw10S
              stephenw10 Netgate Administrator
              last edited by

              That's true but this is in the system log. It looks like the client renewing the lease, no?  :-\

              Steve

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              • chpalmerC
                chpalmer
                last edited by

                Just DHCP broadcasts…   If I take the block out I get similar in the logs 24/7...    My address still changes from time to time so I know I haven't blocked it...  But if I let it log I miss other traffic I might want to see due to the constant traffic from my ISP's server...   In my case 10.28.0.1...

                So unless the pfSense box is making constant DHCP requests to the ISP Id have to believe its just DHCP related chatter from the cable system and other customers...

                (insert the shrugging shoulders smiley here...)

                Triggering snowflakes one by one..
                Intel(R) Core(TM) i5-4590T CPU @ 2.00GHz on an M400 WG box.

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                • C
                  cmb
                  last edited by

                  The reason you see the log in the original post is on WAN IP renewal. No way to hide it, nor do you want to really. It'll log that on every DHCP renewal, which happens every half of the lease time. So if your ISP uses a very short lease time it will show up frequently.

                  @chpalmer:

                  10.244.64.1 is not private space.  if it was you would also need to uncheck "Block private networks" on your WAN interface…

                  No, 10.* is private space, and block private networks strictly blocks ingress unsolicited traffic. The DHCP request is allowed out, the reply back in by the state.

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                  • chpalmerC
                    chpalmer
                    last edited by

                    @cmb:

                    The reason you see the log in the original post is on WAN IP renewal. No way to hide it, nor do you want to really. It'll log that on every DHCP renewal, which happens every half of the lease time. So if your ISP uses a very short lease time it will show up frequently.

                    @chpalmer:

                    10.244.64.1 is not private space.  if it was you would also need to uncheck "Block private networks" on your WAN interface…

                    No, 10.* is private space, and block private networks strictly blocks ingress unsolicited traffic. The DHCP request is allowed out, the reply back in by the state.

                    Host name:
                    ip-10-244-64-1.us-west-1.compute.internal

                    Thats what I thought off the top of my head but a quick (and obviously not to observant )look came back with a host name to us-west…  I didn't catch the "internal" part...

                    dhclient[18753]: DHCPREQUEST on re0 to 10.244.64.1 port 67

                    And read that too quick…  Thought it was incoming....  Ignore me    Im going back to bed!    ::)

                    Triggering snowflakes one by one..
                    Intel(R) Core(TM) i5-4590T CPU @ 2.00GHz on an M400 WG box.

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                    • C
                      cmb
                      last edited by

                      @chpalmer:

                      dhclient[18753]: DHCPREQUEST on re0 to 10.244.64.1 port 67

                      And read that too quick…  Thought it was incoming....  Ignore me    Im going back to bed!    ::)

                      I'm sure you were thinking of the usual scenario people post here with floods of blocked DHCP requests and/or replies, which is the norm with cable since it's a gigantic broadcast domain. That's firewall logs though, in this case it's dhclient renewals.

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                      • stephenw10S
                        stephenw10 Netgate Administrator
                        last edited by

                        Ha, good to see I'm not loosing my mind. Yet.  ;)

                        Steve

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