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    0.0.0.0:68 -> 255.255.255.255:67 Blocked (Can't unblock)

    Scheduled Pinned Locked Moved Firewalling
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    • H
      HowardSten98239
      last edited by

      One thing I noticed on my WAN (with a default install) is that traffic from SOURCE 0.0.0.0:68 to DEST 255.255.255.255:67 (UDP) is getting blocked. This is preventing me from getting an address from DHCP. If I "Easy Rule" this and allow the traffic in the firewall, it still blocks it. I don't have any additional rules explicitly blocking this, since its a pretty vanilla install.

      My guess is that its possibly caused by "Block private networks" and/or "Block bogon networks". Is that a good guess? If it is those, is it possible to keep those enabled but allow for DHCP traffic?

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      • awebsterA
        awebster
        last edited by

        I think what you are seeing is actually another device on the WAN side trying to do DHCP. 
        This would be the expected behaviour, as you're not running a DHCP server on the WAN side.

        –A.

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        • johnpozJ
          johnpoz LAYER 8 Global Moderator
          last edited by

          As awebster mentions that is a dhcpdiscover, that is some client asking for IP from dhcp, has nothing to do with pfsense getting an IP via dhcp.

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          • C
            cmb
            last edited by

            Yep, nothing to do with your DHCP client. Power cycle your modem (assuming that's what WAN is plugged into) after changing devices, that's almost always why you can't pick up a lease.

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            • R
              RafterX
              last edited by

              First: Bumping very old topic I know, but I believe still very relevant to clarify. Also, this forum topic was top on my searchlist when searching on this subject ;-)

              The reason I came upon this thing, was my firewall(pfsense) log, getting filled up with these entries every 3 seconds.

              I have also struggled to find out what the heck this was. I have spent loads of time on it. In the end, trial and error, leaving out every network part 1 by 1.

              I found out, it comes from the ISP local-internet(whats it called?), all the isp-costumers, and when someone's modem is starting up, it sends dhcp request out on the network, speeding right through my isp-modem because it is in bridge mode, and ends up on the WAN-side of my pfsense router. Therefore the block bogon(private range ip-adresses), in the firewall log.

              In pfsense firewall and settings, I can tick off to NOT log those "block bogon" packets, if I those to.

              RafterX out.

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