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

    Network Discovery not working on VLAN

    Scheduled Pinned Locked Moved L2/Switching/VLANs
    4 Posts 2 Posters 751 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.
    • HermanH
      Herman
      last edited by

      Hi Folks,

      I am still figuring out pfSense and VLAN’s. The problem I’m facing is that I do not get Network Discovery working from LAN1 to the VLAN20. My situation is;

      LAN1: 10.0.0.x
      VLAN20: 10.0.20.0

      The VLAN20 is working properly and without problem so far. What isn’t working is network discovery. When run a IP scanner on the 10.0.0.0 net and scan the VLAN20 it will not find any devices on the VLAN. I think the Broadcast is the issue because VLANs not pass Broadcast, right? For the record, IP scanning LAN1 finds every device on LAN1.

      Is there a way to get this working. Do I have to create rules on the VLAN? Already I’ve created one rule named “Default allow VLAN20 to any rule”. This is working cause all the devices on the VLAN20 can access the internet.

      9554adab-14fa-4d24-812e-63c052ac973d-image.png

      Any ideas where to find the solution?

      Kind regards,
      Herman F.

      Limburg | The Netherlands.
      It is nice to be important. But it is more important to be nice! | Failure, the best teacher it is!

      1 Reply Last reply Reply Quote 0
      • JKnottJ
        JKnott
        last edited by

        How does that scanner work? If it uses ARP requests, it will never scan past the router to the VLAN. I don't think broadcasts are used for that these days as many systems will not respond to a broadcast ping. In fact, I just tried it on my network and didn't get a single response. There are Linux, Windows and other devices on my network and none of them replied. However, as you say, if they are, they won't pass through the router. Before we can advise you, we need to know how the scanning is done.

        PfSense running on Qotom mini PC
        i5 CPU, 4 GB memory, 32 GB SSD & 4 Intel Gb Ethernet ports.
        UniFi AC-Lite access point

        I haven't lost my mind. It's around here...somewhere...

        HermanH 1 Reply Last reply Reply Quote 0
        • HermanH
          Herman @JKnott
          last edited by

          Hello @JKnott,

          Sorry for the late reply. Was verf bust with work.

          For scanning the network I uwe Advanced IP scanner. Software can be downloaded for free.
          When I scan the Vlan it only shows IP adresses in the whole range. Also when I use the Windows netwerking icon, I only see devices in the LAN and not the devices in the Vlan.

          Try to figure out how routing is done between Lan and VLan...

          Does this help?

          Regards,
          Herman.

          Limburg | The Netherlands.
          It is nice to be important. But it is more important to be nice! | Failure, the best teacher it is!

          JKnottJ 1 Reply Last reply Reply Quote 0
          • JKnottJ
            JKnott @Herman
            last edited by

            @Herman said in Network Discovery not working on VLAN:

            Does this help?

            No, I'm not familiar with that software and it doesn't answer my question. How does it scan? You can fire up Wireshark or packet capture to see what's on the wire.

            PfSense running on Qotom mini PC
            i5 CPU, 4 GB memory, 32 GB SSD & 4 Intel Gb Ethernet ports.
            UniFi AC-Lite access point

            I haven't lost my mind. It's around here...somewhere...

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