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

    DHCP Relay Listening on ALL Interfaces!

    Scheduled Pinned Locked Moved DHCP and DNS
    3 Posts 1 Posters 363 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.
    • ?
      A Former User
      last edited by A Former User

      Hi,

      I have a DHCP server in my local network (192.168.1.10/24) and multiple LAN interfaces on my pfSense (192.168.1.254) box (WiFi, DMZ, GUESTS and so on).

      So I configured pfSense to be a DHCP relay for my DHCP server for all interfaces where the DHCP is not directly attached to.

      This works fine so far- all clients arer getting IP addresses from the DHCP server through the pfSense.

      But the pfSense is listening on the local interface, too! So for every client which requests an address the DHCP server sees two queries:

      Feb 21 07:04:26 praxis dhcpd[8092]: DHCPDISCOVER from 54:04:a6:a4:73:de via eth0
      Feb 21 07:04:26 praxis dhcpd[8092]: DHCPOFFER on 192.168.1.52 to 54:04:a6:a4:73:de via eth0
      Feb 21 07:04:26 praxis dhcpd[8092]: DHCPDISCOVER from 54:04:a6:a4:73:de via 192.168.1.254
      Feb 21 07:04:26 praxis dhcpd[8092]: DHCPOFFER on 192.168.1.52 to 54:04:a6:a4:73:de via 192.168.1.254
      Feb 21 07:04:27 praxis dhcpd[8092]: DHCPREQUEST for 192.168.1.52 (192.168.1.10) from 54:04:a6:a4:73:de via eth0
      Feb 21 07:04:27 praxis dhcpd[8092]: DHCPACK on 192.168.1.52 to 54:04:a6:a4:73:de via eth0
      Feb 21 07:04:27 praxis dhcpd[8092]: DHCPREQUEST for 192.168.1.52 (192.168.1.10) from 54:04:a6:a4:73:de via 192.168.1.254
      Feb 21 07:04:27 praxis dhcpd[8092]: DHCPACK on 192.168.1.52 to 54:04:a6:a4:73:de via 192.168.1.254
      Feb 21 07:06:50 praxis dhcpd[8092]: DHCPINFORM from 192.168.1.52 via eth0
      Feb 21 07:06:50 praxis dhcpd[8092]: DHCPACK to 192.168.1.52 (54:04:a6:a4:73:de) via eth0
      Feb 21 07:06:50 praxis dhcpd[8092]: DHCPINFORM from 192.168.1.52 via 192.168.1.254
      Feb 21 07:06:50 praxis dhcpd[8092]: DHCPACK to 192.168.1.52 (54:04:a6:a4:73:de) via eth0
      

      You see every sequence is doubled so the client is busy in requesting it's IP address through relay as well directly. This is crappy and I have some older clients which can not deal with it.

      So how can I prevent dhcp relay to listen on LAN interface? According to configuration it shouldn't!
      dhcp.png

      /KNEBB

      1 Reply Last reply Reply Quote 0
      • ?
        A Former User
        last edited by

        Hi,

        I had the suspection it might have to do with VLANs as the interfaces where the relay should listen to are configred as VLANs on physical interface.

        Changed this meanwhile but still the same!

        So for sure DHCP-Relay listens on interfaces where it should not to!

        Is there anywhere a bugtracker where I can enter a bug?

        /KNEBB

        1 Reply Last reply Reply Quote 0
        • ?
          A Former User
          last edited by

          Found it on my own.

          Entered it there.

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