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    Can't change nic mac adress without modem lights

    Scheduled Pinned Locked Moved 2.0-RC Snapshot Feedback and Problems - RETIRED
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    • ? This user is from outside of this forum
      Guest
      last edited by

      If I change the mac address on the adapter on the nic, my modem connected to it, the lights for LAN will flash for a few seconds then off.

      Cycle repeats nonstop.

      Modem is a sb5101.

      Anyone else have a similar problem?

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      • johnpozJ Offline
        johnpoz LAYER 8 Global Moderator
        last edited by

        Normally if you change the mac of the interface connected to a modem, you need to power cycle the modem to connect tot he new mac.  I know this is how it on on my current SB6120, and on the one before that which was also a motorola SB51xx series I don't recall if was 5120 or just 5100, etc. and then even the one before that was the same way.

        http://homepage.ntlworld.com/robin.d.h.walker/cmtips/swap.html
        Cable Modem Troubleshooting Tips

        Swapping computers on the cable modem

        Most domestic cable ISPs (including NTL, Blueyonder) have the cable modem configured to recognise only one client PC, by the MAC address of its network interface. Once the cable modem has learnt the MAC address of the first PC that talks to it, it will not respond to another MAC address in any way. Thus if you swap one PC for another (or for a router), the new PC (or router) will not work with the cable modem, because the new PC (or router) has a different MAC address to the old one. To reset the cable modem so that it will recognise the new PC, you must power the cable modem off and on again.

        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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        • ? This user is from outside of this forum
          Guest
          last edited by

          Yeah, I know that though. Power cycled the modem several times. Although when what you descrbes happens, the modem will happily LAN conenct to the pc, but won't allow Internet.

          I also found that out when I was messing with my old sb6120.

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          • johnpozJ Offline
            johnpoz LAYER 8 Global Moderator
            last edited by

            I have seen where when I reboot my sb6120 that it likes to hand out 192.168.100 addresses.. So maybe that would explain no internet.. I would suggest disconnect your device, change its mac – power cycle the modem and let it finish its sync and powerup etc before connecting anything to it.

            Also what mac you using?  Sure its a valid one, sure nobody else on your isp network could be using it?

            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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            • ? This user is from outside of this forum
              Guest
              last edited by

              Nah it's not the the things you mentioned. I've had that problem before, the link light is always blinking when that happens though.

              Here the link light blinks 3 times, pfsense then says disconnected. My log gets spammed for my modem of disconnects.

              It doesn't even get a change to negotiate an ip address.

              This only happens when spoofing. Like if I say hook my laptop up to the modem when it boots up, and then plug it into my router with no spoofing, I won't get an IP but it will happily communicate via the LINK and it will flash a lot.

              Here if I spoof regardless, it just blinks and then stops.

              Modem log is spammed with ethernet disconect and reconnect.

              Also tried lots of random macs, same problem… I think the problem is with pfsense. (I am rebooting the modem after pfsense is done loading)

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              • johnpozJ Offline
                johnpoz LAYER 8 Global Moderator
                last edited by

                "(I am rebooting the modem after pfsense is done loading)"

                Disconnect the MODEM from pfsense before you change the mac..

                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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                • ? This user is from outside of this forum
                  Guest
                  last edited by

                  OFC.
                  It still doesn't work.

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                  • G Offline
                    GoldServe
                    last edited by

                    I have the exact same error too. Changing the MAC address will cause the interface to go up -> down -> up -> down. When I remove the interface mac address, it is all normal again and I notice the interface MAC has changed to what I want it to be. See if that is the case for you!

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