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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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    • K
      kejianshi
      last edited by

      Skype comes back up pretty fast - Thats a minor annoyance.

      What are you using the ssh sessions for?

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      • S
        stpq
        last edited by

        skype: minor, but still anoyance…
        ssh...

        well for whats it meant to, beginning with simple remote access, going through x11 export and sometimes some tunneling....

        how is that important for diying of sessions?

        and dont take me wrong, i have dropped same IP for different mac a long while ago, to begin with (i begin with users) because of some os (like window$ whatever version) is not able to take same ip on two ifaces, continuing through migration of dhcp to zeroshell, using pools instead of static definitions of ips for the clients and so and so...  Im just saying that sometimes, specially in small network/home environments it can be useful....

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        • K
          kejianshi
          last edited by

          I think the cure for you might be to install a headless server that doesn't have to move here and there and everywhere to handle all that and just use your laptop for everything else.

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          • DerelictD
            Derelict LAYER 8 Netgate
            last edited by

            Or just get good wireless and stay on it even when docked.

            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
              johnpoz LAYER 8 Global Moderator
              last edited by

              "Or just get good wireless and stay on it even when docked."

              Exactly – here is the thing if your going to be changing networks, you have to expect that a session would die, just reconnect - I don't see an issue here at all.  if I had a ssh session open and I went from wired to wireless - then yeah that session would have to be reopened.  What is the saying you can't fix stupid ;)  Anyone that would think they can maintain sessions while changing their connection type doesn't understand networking ;)

              Even if you move your IP to a different nic - your session like ssh is still going to die..

              So your complaint is your ssh client doesn't reconnect for you?

              As stated to solve your problem don't move your connection - use wireless while docked or undocked, there you go problem solved you never loose your connection ;)

              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
              SG-4860 24.11 | Lab VMs 2.7.2, 24.11

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              • K
                kejianshi
                last edited by

                Unless your wireless drops…  Which never happens (-;

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                • DerelictD
                  Derelict LAYER 8 Netgate
                  last edited by

                  Which is why I said good wireless, not some $19 tp-link from walmart.

                  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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                  • S
                    stpq
                    last edited by

                    "Even if you move your IP to a different nic - your session like ssh is still going to die.."
                    ehm, nope..

                    "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?

                    wireless…. hmm... something like AC than, and even that wont give u gigabit... wire is wire and wireless sux, regardless the price of it..

                    And again, dont take me wrong, as i stated earlier... I  just think, that it can be a valid argument... I mean its implementen in ISC.. its a feature, not a liability...

                    s

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                    • DerelictD
                      Derelict LAYER 8 Netgate
                      last edited by

                      So you want:

                      1: the speed of Gig-E when you're wired
                      2: the convenience of wireless when you're not
                      3: total disregard for the OSI model when you switch between them.

                      Got it.

                      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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                      • K
                        kejianshi
                        last edited by

                        I'm convinced personally - I'm switching all my servers to wifi (-;

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                        • S
                          stpq
                          last edited by

                          @Derelict:

                          So you want:

                          1: the speed of Gig-E when you're wired
                          2: the convenience of wireless when you're not
                          3: total disregard for the OSI model when you switch between them.

                          Got it.

                          you are totally right…

                          but look at this: https://forum.pfsense.org/index.php/topic,36066.msg186013.html#msg186013

                          so it still might be possible...

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

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                          • DerelictD
                            Derelict LAYER 8 Netgate
                            last edited by

                            No.  It violates the OSI model having two interfaces with the same MAC or two MACs with the same IP.

                            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)

                            1 Reply Last reply Reply Quote 0
                            • DerelictD
                              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
                                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
                                SG-4860 24.11 | Lab VMs 2.7.2, 24.11

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                                • C
                                  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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