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

    Static DHCP Mapping on LAN (dynamic IP) Affects DNS Servers on Other Interfaces

    Scheduled Pinned Locked Moved DHCP and DNS
    2 Posts 1 Posters 313 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.
    • cwagzC
      cwagz
      last edited by

      I was just troubleshooting a very weird issue.

      My phone has a static mapping on the LAN interface but uses a dynamically allocated IP from the pool. I run several different Piholes that different devices use to control access to YouTube mainly to protect my kids. My static mapping points to the YouTube unrestricted PiHoles as DNS Servers.

      I was setting up a new SSID (VLAN) to use for my work laptop and testing it with my iPhone. The Interface for this VLAN had all default setting for DHCP and should have just assigned an IP address along with the interface IP for DNS. My Piholes are going to stay on the other VLAN and are not accessible from this SSID / VLAN.

      When my iPhone connected to this VLAN it would pick up a correct IP from the DHCP pool, but it was getting assigned the DNS servers that are part of the static mapping on my LAN interface!

      To test this theory, I turned on the "Private Wi-Fi Address" feature on the iPhone which generated a new MAC for the phone when connecting to this SSID / VLAN. The DHCP server now correctly assigned the VLAN interface address as the DNS server and everything works normally.

      I am running 22.05 on a 6100 max.

      Seems like a bug. Any suggestions on what I could be missing?

      These are the static mapping / DNS servers carrying over to the "WFH" Interface:
      e11c5031-c2c3-4d8f-ae18-a41540ad9105-image.png

      Netgate 6100 MAX

      1 Reply Last reply Reply Quote 0
      • cwagzC
        cwagz
        last edited by

        Should I just enter this in redmine? It seems like it would be pretty easy to reproduce. At least on my system I can reproduce it at will.

        Netgate 6100 MAX

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