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

    Ipv6 multicast being blocked on lan?

    Scheduled Pinned Locked Moved IPv6
    5 Posts 4 Posters 10.4k 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.
    • johnpozJ
      johnpoz LAYER 8 Global Moderator
      last edited by

      So maybe I have missed them but have noticed stuff like this now

      block
      Aug 12 10:41:42 LAN [fe80::794f:b5ca:8dc7:92d7]:52956 [ff02::1:3]:5355 UDP

      block
      Aug 12 10:41:38 LAN [fe80::794f:b5ca:8dc7:92d7]:63672 [ff02::c]:1900 UDP

      Might have been going on for quite some time and just now noticed, but shouldn't lan rule

      IPv6 * LAN net  as source to * destination allow for this?

      If not what rule needs to be put in to allow?

      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 24.11 | Lab VMs 2.7.2, 24.11

      1 Reply Last reply Reply Quote 0
      • D
        databeestje
        last edited by

        port 1900 udp is upnp iirc. and i think 5535 is bonjour of sorts. not too sure about that one.

        The ff02:: range is a special range which is not covered by the LAN rule. LAN net expands to the global address and not the link local address of that interface.

        The ff02 is a multicast address used for registering routers and dhcp servers etc. You'd need to look that specific address up for what service it is.

        1 Reply Last reply Reply Quote 0
        • johnpozJ
          johnpoz LAYER 8 Global Moderator
          last edited by

          5355 is LLMNR, I have turned it off in group policy on the machine sending it.. I personally have no use for it ;)  and I clearly don't need SSDP either so turning that crap off as well ;)

          But I think I more curious why this traffic is being logged, but why no ipv4 multicast is being logged.. I would assume its blocked as well?  Or does lan net include the ipv4 multicast?

          isn't all traffic that is blocked by the default rule logged?  So it must be allowing multicast on ipv4?  But not on ipv6 link-local addresses?

          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 24.11 | Lab VMs 2.7.2, 24.11

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

            are u using windows 7? it prefers ipv6 over ipv4 from what i can tell…its probably not sending any ipv4 out since ipv6 is working on your network....

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

              @johnpoz:

              isn't all traffic that is blocked by the default rule logged?  So it must be allowing multicast on ipv4?  But not on ipv6 link-local addresses?

              exactly. Your LAN rules aren't permitting your link local sourced traffic, where with v4 they're sourced from a LAN IP which is permitted. Granted it's not forwarding that multicast traffic, but it's not blocking it either with v4.

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