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    MAC based DNS possible?

    DHCP and DNS
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    • 3
      32smooth
      last edited by

      Hello,

      I'm a bit confused by the DHCP Static leases feature. It offers to add entries without static IP. When I add one without IP, and a the client with the given Mac goes online, I see 2 entries in the Status -> DHCP leases page and that client can not be accessed by the hostname that I specified in the static lease.

      I'd like to define hostname for clients based on their MAC address so that I can access them by that hostname. The IP should not be relevant, hence I don't want to specify any IPs.

      Is that possible?

      many thanks!

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      • JKnottJ
        JKnott
        last edited by

        Yes you are confused.  While some protocols map a name to the MAC address, IP does not.  You can configure the DHCP server to reserve an address and also add a name to DNS.  It's also possible for the device to pass it's name to the DHCP server and then allow the DHCP server to provide the name to DNS.

        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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        • K
          kpa
          last edited by

          Not possible, the DNS standard deals only with IP addresses and all matters related to IP address - MAC address pairings are irrelevant to DNS. You already have the next best thing which is static DHCP leases with the registration of the static lease IP addresses to the DNS forwarder/resolver.

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          • 3
            32smooth
            last edited by

            thanks for the replies. I thought it would make little difference for an orchestrated dns/dhcp setup to bind the name to an ip from the dhcp-pool instead of a predefined one. But ok, you learn new things all the time :)

            Best regards,
            Smooth

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            • H
              Harvy66
              last edited by

              I thought it would make little difference for an orchestrated dns/dhcp setup to bind the name to an ip from the dhcp-pool

              That's called leaky abstractions. While it seems like a good idea for simple setups, it's a slippery slope of cans of worms.

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              • JKnottJ
                JKnott
                last edited by

                Also, doing this would require overhauling the entire DNS system.  Then there's the issue of MAC addresses being meaningless off the local network.

                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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                • K
                  kpa
                  last edited by

                  Also, it is possible to build IP networks that do not have MAC addresses at all.

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