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    Roku won't connect to internet if both of it's MAC addresses are assigned the same IP

    Scheduled Pinned Locked Moved DHCP and DNS
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    • johnpozJ
      johnpoz LAYER 8 Global Moderator @imthenachoman
      last edited by johnpoz

      So it doesn't auto switch - you have to manually switch it over.. Right?

      Setting 2 different macs to have the same IP not good idea. If your setting rules or something - just set the rules for both its IPs the .x one and the .y one.

      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 2.8, 24.11

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      • I
        imthenachoman @johnpoz
        last edited by

        @johnpoz Okay but in theory it should work, right?

        Only one MAC address will be connected to pfSense at a time. So I am curious why it doesn't work when logically I feel like it should.

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

          Are you setting the mac via static on the device? dhcp will not allow you to set a reservation for the same IP, to different macs..

          You have no idea how they have it coded.. I would think most OSes would scream at you for trying to set 2 different interfaces to the same IP.

          error.png

          Like I said - its a bad idea to do such a thing.. Just use .x and .y for your 2 different interfaces.

          edit: Are you one of those people that would name all of your kids the same name ;) This is Billy, and this is also Billy ;)

          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 2.8, 24.11

          JKnottJ I 2 Replies Last reply Reply Quote 0
          • JKnottJ
            JKnott @imthenachoman
            last edited by

            @imthenachoman

            One thing I just thought of, Roku runs Linux IIRC. With Linux, you can do what you want, but you use different addresses on the connections. This works very well with my ThinkPad. Linux uses a metric, to choose the best connection. Ethernet has a lower metric than WiFi, so it gets used when available.

            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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            • JKnottJ
              JKnott @johnpoz
              last edited by

              @johnpoz said in Roku won't connect to internet if both of it's MAC addresses are assigned the same IP:

              This is Billy, and this is also Billy ;)

              This is my brother Daryl and this is my other brother Daryl. Fans of Bob Newhart will recognize that one. 😉

              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...

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

                Yeah this is my brother Darryl would of been a better choice to use in my example :)

                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 2.8, 24.11

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                • I
                  imthenachoman @johnpoz
                  last edited by

                  @johnpoz said in Roku won't connect to internet if both of it's MAC addresses are assigned the same IP:

                  Are you setting the mac via static on the device? dhcp will not allow you to set a reservation for the same IP, to different macs..

                  Nope. Setting via static assignment to MAC from pfSense.

                  @johnpoz said in Roku won't connect to internet if both of it's MAC addresses are assigned the same IP:

                  You have no idea how they have it coded.. I would think most OSes would scream at you for trying to set 2 different interfaces to the same IP.

                  Only if both interfaces are trying to connect at the same time, no? if one is not active/used then the OS shouldn't/wouldn't know. No?

                  @johnpoz said in Roku won't connect to internet if both of it's MAC addresses are assigned the same IP:

                  Like I said - its a bad idea to do such a thing.. Just use .x and .y for your 2 different interfaces.

                  Understood that it doesn't work. I am trying to wrap my head around why when it logically makes sense that it should. From pfSense's point of view, the Roku is only connected once -- either Ethernet or wired -- so it shouldn't have an issue with using the same IP. It would be just like the DHCP server handing out a previously used but currently unused IP to a new device with a new MAC because the original device is no longer active/connected.

                  @johnpoz said in Roku won't connect to internet if both of it's MAC addresses are assigned the same IP:

                  edit: Are you one of those people that would name all of your kids the same name ;) This is Billy, and this is also Billy ;)

                  No, but if my kid has two names, a first and a nick, I would expect the rules applied to the kid to apply regardless of which one is called.

                  • Rule: [child first name] will never, under any circumstance do ABC
                  • Some random person to [child nick name]: "go do ABC"

                  A device is a device, regardless of how it is connected. Since FW rules are done on IPs it makes sense that one device with two names (two MAC addresses) should look and act as one device on the FW.

                  @jknott said in Roku won't connect to internet if both of it's MAC addresses are assigned the same IP:

                  This is my brother Daryl and this is my other brother Daryl. Fans of Bob Newhart will recognize that one.

                  I recognize that line from a Blood Hound Gang song. :)

                  johnpozJ JKnottJ 2 Replies Last reply Reply Quote 0
                  • johnpozJ
                    johnpoz LAYER 8 Global Moderator @imthenachoman
                    last edited by

                    @imthenachoman said in Roku won't connect to internet if both of it's MAC addresses are assigned the same IP:

                    Nope. Setting via static assignment to MAC from pfSense.

                    And how are you doing that?

                    Oh I just tried - and doesn't stop you from setting that.. But you still have a problem.. So wired has a lease open lets say.. Now your switch shits the bed.. And it needs to go to wireless - how is going to hand out that lease, where there is already a lease for that IP..

                    Since FW rules are done on IPs it makes sense that one device with two names (two MAC addresses) should look and act as one device on the FW.

                    No - rules are IP based.. Different mac address should not have the same IP.. If you do - you going to have problems..

                    Your going about this the hard way... Again create an alias with your 2 IPs in it, your wired IP, and your wireless IP. Use that alias in your rules. Done! There is no reason to want to use the same IP for different macs.

                    Where you also run into an issue with your auto switch idea... Pfsense has mac A in its arp cache for 192.168.1.100.. Now wired is gone, and you want mac B to be used for 192.168.1.10 - but arp cache for 192.168.1.100 already points to mac A..

                    If you use different IP for your different mac - that is never an issue.

                    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 2.8, 24.11

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                    • I
                      imthenachoman @johnpoz
                      last edited by

                      @johnpoz said in Roku won't connect to internet if both of it's MAC addresses are assigned the same IP:

                      And how are you doing that?

                      995828b1-f154-4339-8105-11d4cf1c127c-image.png

                      @johnpoz said in Roku won't connect to internet if both of it's MAC addresses are assigned the same IP:

                      So wired has a lease open lets say.

                      I see. So that's why the wired connection won't work when I have a static assignment for the wifi MAC but it does work if delete said static assignment. Got it.

                      @johnpoz said in Roku won't connect to internet if both of it's MAC addresses are assigned the same IP:

                      rules are IP based..

                      Yeah.

                      @johnpoz said in Roku won't connect to internet if both of it's MAC addresses are assigned the same IP:

                      Different mac address should not have the same IP..

                      But that is bound to happen with a DHCP server and no static mapping right? MAC1 connects, gets IP 1. MAC1 disconnects. Months later MAC2 connects. MAC2 might get IP 1 since IP 1 is available. No?

                      @johnpoz said in Roku won't connect to internet if both of it's MAC addresses are assigned the same IP:

                      arp cache

                      Got it. Now I get why it doesn't work even though it logically sounds like it should. I forgot about the cache. The cache is linking an IP to a mac address. So when there are two IPs tied to a mac, the device can get an IP but won't have any network access. Got it. Thanks!

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                      • JKnottJ
                        JKnott @imthenachoman
                        last edited by

                        @imthenachoman said in Roku won't connect to internet if both of it's MAC addresses are assigned the same IP:

                        I recognize that line from a Blood Hound Gang song. :)

                        Newhart

                        Check the cast.

                        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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