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

    Multicast DNS to interface address instead of 224.0.0.251

    Firewalling
    1
    1
    327
    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.
    • ?
      A Former User
      last edited by

      Hi all,

      I would appreciate if one could help me with the following question.
      I have Multicast DNS enabled through 'udpbroadcastrelay'. Functionality is working fine.
      On the relevant interfaces, I have established allow rules (incl. IP-options) that allows UDP traffic from the interface network (IOT in my case) towards 224.0.0.251:5353 as destination.

      Last weekend, I dug into logs, and found out that there's quite some devices that initiate mDNS traffic, but instead of the multicast address as destination, they point towards the interface address of that interface. Like so:

      mdns.png

      I am rejecting the traffic, so I guess this is not a big deal, knowing it's working, but I wonder why this traffic gets initiated in the first place. Has anyone else encountered this before? Should I put in place a pass rule to allow this type of traffic?

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