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    Is it possible to assign the same static IP for two different MAC addresses?

    Scheduled Pinned Locked Moved DHCP and DNS
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    • DerelictD Offline
      Derelict LAYER 8 Netgate
      last edited by

      @stpq:

      and does it violate OSI model to have two interfaces with addresses from the same subnet?

      You have two interfaces:  eth0 at 192.168.1.13 and eth1 at 192.168.1.14

      Your default gateway is 192.168.1.1

      Which interface(s) should be used to send traffic to the gateway?

      It's not against the model, but requires special consideration and per-interface (not just per-subnet) routing rules.

      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!
      Do Not Chat For Help! NO_WAN_EGRESS(TM)

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      • johnpozJ Online
        johnpoz LAYER 8 Global Moderator
        last edited by

        @stpq:

        "So your complaint is your ssh client doesn't reconnect for you?"
        yeah, but do u have any clue how long it takes for ssh to timeout?

        Would depend on the settings in ssh server.  What are the settings for ClientAliveInterval, TCPKeepAlive and ClientAliveCountMax?  They could be very short, or very long depending on what the admin of the ssh server set.

        Where is this a ISC dhcp feature - just because you can get something to load and function in the config, does not mean its a SMART thing to do ;)  You can do lots of things that some software will allow - doesn't mean its good practice ;)

        Networking 101, mac's are suppose to be unique.  You wouldn't want the same IP address on different macs..

        An intelligent man is sometimes forced to be drunk to spend time with his fools
        If you get confused: Listen to the Music Play
        Please don't Chat/PM me for help, unless mod related
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        • C Offline
          Cino
          last edited by

          I agree with what everyone is saying but there is a way to assign the same static IP to two different MACs. I do it if I assign a static IP to a device that has multiple interfaces (WDTV, Roku 3, TVs, Work Laptop)

          This is not supported by pfsense and could break your system if you mess up!!! I hold no responsible if you break your system nor do I offer support. But I am willing to share the knowledge of how it can be done

          You will have have to manually edit your config.xml… Goto you the <dhcpd>section then look for <staticmap>... You should get the idea of how to do this...Once you save your changes, reboot your box..

          
          			 <staticmap><mac>00:19:9d:12:9f:4c</mac>
          				<ipaddr>192.168.0.51</ipaddr>
          				<hostname>vizio</hostname>
          
          				 <filename><rootpath></rootpath></filename></staticmap> 
          			 <staticmap><mac>00:19:9d:08:dc:05</mac>
          				<ipaddr>192.168.0.51</ipaddr>
          				<hostname>vizio</hostname></staticmap> 
          
          

          Capture.JPG
          Capture.JPG_thumb</staticmap></dhcpd>

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