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    Notify on unknown MAC address?

    DHCP and DNS
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    • AmarandA
      Amarand
      last edited by

      I run a fairly tight ship on my network, needing to know every single device with a static MAC to IP mapping.

      I do have an upper-range pool of dynamic IP addresses that can be assigned, which gets the user on the network, but I'd like to be notified when that happens.

      There are -two- times this happens on my network:

      1. Someone buys a new device and we forget to add it to the DHCP server.
        (This triggers us to add the MAC/IP pair to the DHCP server.)

      2. One of the iOS devices (like iPhone, iPad, Apple Watch) gets into Private MAC Address mode, and issues random MAC addresses.
        (We need to hunt down the device and disable Private MAC Address mode.)

      I keep the pool down to about 15 addresses, and sometimes a "perfect storm" can use up all 15 of them (if someone has Private MAC Address mode enabled, and they try to connect to multiple WiFi connections, that's one fresh MAC address per connection!) so it might be nice to know "hey, something new registered...." via email or text or something.

      Is this a built-in option? A plugin? Not yet a feature?

      I know that some environments have "block and report" on all unknown MAC addresses. I don't mind the "block" as long as there's an immediate "report" so I know that a DHCP failure is caused by an unknown MAC.

      Thanks!

      johnpozJ 1 Reply Last reply Reply Quote 0
      • johnpozJ
        johnpoz LAYER 8 Global Moderator @Amarand
        last edited by johnpoz

        @amarand sounds like arpwatch would be what your after.. It can email you whenever a new mac is seen on your network.

        Just a package you can install.

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        AmarandA 1 Reply Last reply Reply Quote 1
        • AmarandA
          Amarand @johnpoz
          last edited by

          @johnpoz

          arpwatch, thanks!

          1 Reply Last reply Reply Quote 0
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