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    Assign unique MAC to vlan interface?

    Scheduled Pinned Locked Moved L2/Switching/VLANs
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    • C
      coreybrett
      last edited by

      Is is possible to assign a unique MAC address to a VLAN interface?

      In other words, can a vlan interface has a MAC that is different than its real interface?

      On the XG-7100, all the interfaces that are configured using the builtin switch, have the same MAC by default, and I think that is causing an issue for me where I have two interfaces (different IPs) connected to the same switch.

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      • JKnottJ
        JKnott
        last edited by

        @coreybrett said in Assign unique MAC to vlan interface?:

        Is is possible to assign a unique MAC address to a VLAN interface?

        I doubt it. The only difference between a VLAN frame and non-VLAN frame coming out of the same interface is the VLAN tag. Other than configuring a locally assigned MAC, pfSense has no influence on the MAC address, which is added by the NIC, when the frame is transmitted..

        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...

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        • DerelictD
          Derelict LAYER 8 Netgate
          last edited by

          Yeah. a MAC address does not exist on a switch port unless it has a layer 3 interface there.

          As @jknott said all layer 3 traffic on all switch ports will have the same MAC address in general.

          You should not have two interfaces connected to another layer 2 device. If you are connecting two XG-7100 switch ports to another switch, they should be connected to ports in different VLANS (which would not mind the MAC addresses being the same) or in a LAGG.

          Chattanooga, Tennessee, USA
          A comprehensive network diagram is worth 10,000 words and 15 conference calls.
          DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
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          • JKnottJ
            JKnott @Derelict
            last edited by

            @derelict said in Assign unique MAC to vlan interface?:

            As @jknott said all layer 3 traffic on all switch ports will have the same MAC address in general.

            Actually, layer 2 traffic too. The MAC address is added when the frame is created in the NIC. Layer 3 is above that.

            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...

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