Netgate Discussion Forum
    • Categories
    • Recent
    • Tags
    • Popular
    • Users
    • Search
    • Register
    • Login

    [RESOLVED] Getting constant alerts/blocks for 255.255.255.255

    Scheduled Pinned Locked Moved pfBlockerNG
    7 Posts 3 Posters 4.1k Views
    Loading More Posts
    • Oldest to Newest
    • Newest to Oldest
    • Most Votes
    Reply
    • Reply as topic
    Log in to reply
    This topic has been deleted. Only users with topic management privileges can see it.
    • C
      charvey
      last edited by

      My firewall alerts tab is filled with warnings about broadcast traffic getting blocked on an internal interface. (See the attached screenshot) The "Wireless" interface represents a network (vlan actually) so I want the broadcast traffic to circulate within the wireless subnet, but not escape from it. I get the feeling from these logs that broadcast traffic is simply not getting broadcast. If that's not true and broadcast traffic is circulating normally on the subnet, then I don't want my alerts tab filling up because it's nothing to worry about. I manually checked my ipv4 block lists, and none of them contain 255.255.255.255.

      Not sure what could be wrong here.

      pfBlockerNg is working perfectly otherwise.

      Thanks,
      Chris
      alert.png
      alert.png_thumb

      1 Reply Last reply Reply Quote 0
      • BBcan177B
        BBcan177 Moderator
        last edited by

        Suspect it's the lvl 1 feed.

        Try this command to find which feed contains that IP:

        grep "^255\." /var/db/pfblockerng/deny/*
        

        "Experience is something you don't get until just after you need it."

        Website: http://pfBlockerNG.com
        Twitter: @BBcan177  #pfBlockerNG
        Reddit: https://www.reddit.com/r/pfBlockerNG/new/

        1 Reply Last reply Reply Quote 0
        • C
          charvey
          last edited by

          @BBcan177:

          Suspect it's the lvl 1 feed.

          Try this command to find which feed contains that IP:

          grep "^255\." /var/db/pfblockerng/deny/*
          

          Empty output :(

          1 Reply Last reply Reply Quote 0
          • C
            charvey
            last edited by

            Just some extra findings/updates from my end.

            Nothing in grep "^255." /usr/local/share/GeoIP/* either.

            I looked at the 'pfblockerng.inc' file to try to figure out what 'no match' means, but it didn't provide any hints. I'd like to check my firewall rules to make sure that 255.255.255.255 is actually listed in the pfblocker generated rules. I'd expect to find 255.255.255.255 in pfB_DNSBLIP.txt. If it's not, I'm not sure where to find the core pfsense firewall rule definitions to check those ip lists.

            I'm still looking into this and I'm open to debugging if anybody has any ideas. I don't know php so things are slow going.

            1 Reply Last reply Reply Quote 0
            • F
              f34rinc
              last edited by

              I looked into your firehol level 1 list and found 224.0.0.0/3 which would include 224.0.0.0 to 255.255.255.255

              The level 1 list includes unrouteable and multicast traffic.  You can still pick and choose the individual lists that make up level 1.

              1 Reply Last reply Reply Quote 0
              • C
                charvey
                last edited by

                I added
                255.255.255.255/32
                and
                224.0.0.0/3

                to the suppress alias and the blocks disappeared!

                Thanks for noticing that line. I'll write a script to test my lists manually next time I get a block like that instead of just relying on grep.

                1 Reply Last reply Reply Quote 0
                • BBcan177B
                  BBcan177 Moderator
                  last edited by

                  See here:
                      https://forum.pfsense.org/index.php?topic=135257.msg764291#msg764291

                  "Experience is something you don't get until just after you need it."

                  Website: http://pfBlockerNG.com
                  Twitter: @BBcan177  #pfBlockerNG
                  Reddit: https://www.reddit.com/r/pfBlockerNG/new/

                  1 Reply Last reply Reply Quote 0
                  • First post
                    Last post
                  Copyright 2025 Rubicon Communications LLC (Netgate). All rights reserved.