XB6 ethernet port wont link in Bridge Mode

[Pyro83]

Hi All,

I have an XB6 modem which I have placed into bridge mode.  For some reason any router I plug into it (tried a few) does not show as connected, nor is a link light present. It was working for 1 month with no problems but stopped for seemingly no reason. I've tried several routers and cables, to no avail.  Changing ports on the modem did not help.  Changing cables did not help. Changing the MAC address of the router did not help.  Interestingly, when I plug a computer directly into it, it seems to link and work about 50% of the time.

I thought I might need to use a crossover cable, but that wouldn't make sense given it was working previously.  

Has anyone had anything similar happen to them, or have any idea what's happening?  

[rstra]

I would try a factory reset. 

https://support.shaw.ca/t5/internet-articles/how-do-i-perform-a-factory-reset-of-my-shaw-internet-mo...

If that doesn’t work, you will probably need to contact Shaw. 

[Pyro83]

Thanks Rstra, I actually tried a factory reset as well to no avail.  

[mdk]

@Pyro83 -- what's happening?  

Your contract for Shaw Internet gives you just one "public" IP-address, with an option to add a second, at no additional cost, if you request it.

Before "bridging" the cable-modem, the cable-modem has "consumed" that one available IP-address.

After "bridging" it, power-off the cable-modem, wait a minute, and power-on the cable-modem. Since it is now "bridged", it will not consume an IP-address.  So, that one IP-address is now available to be assigned to your router. Done.

If you disconnect the router, and instead directly-connect one computer to the cable-modem, things change:

1. if you have been provisioned with a second "public" IP-address, your computer will consume it, and the first IP-address will "stay" with your router, if you reconnect your router to the cable-modem;
2. if you have not been provisioned with a second "public" IP-address, you need to again power-off/power-on the cable-modem, to "release" the only IP-address that Shaw has assigned to you, so that your directly-connected computer can acquire an IP-address.

Such are the limitations of having just one "public" IP-address -- when you change the device (router or computer) directly-connected to the cable-modem, you need to power-off/power-on the cable-modem.

[Pyro83]

Thanks Mdk!  This seems quite likely to be the problem.  I'll check it this weekend and report back.  Thanks!