openVPN through CGN3ACSMR router

[DE_]

I'd like to use the built in VPN capability (openVPN) in my Asus RT-N66U router but the router has to be connected to a private address port of the 4 port switch at the back of the CGN3ACSMR router.  The N66U is objecting to the private address and wants me to set up DDNS which is added complexity I'd like to avoid. If I had just a basic cable modem (is that called a bridge?) with no router or wifi capability the N66U would see the public address I believe. 

I could live without the wireless and switch parts of the CGN3ACSMR. Can Rogers provide a similar speed cable modem if I asked for it ? Can I configure the CGN3ACSMR to make the public address available at its switch ports ?

Any other suggestions / alternatives ? 

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[Datalink · Accepted solution]

Log into the modem, navigate to the BASIC.... GATEWAY FUNCTION, and disable the Residential Gateway Function.  Save the setting and the modem will reboot into Bridge mode where it acts as a modem only.  Your router will have to everything, firewall, routing, port forwarding, etc, etc.

When the router is up and running, if you ever need to log back into the modem to check the signal levels or change the modem back to Gateway mode, you can use 192.168.100.1, thru the router, to log into the modem.  With that address, you don't have to rip your network apart and connect to the modem directly to do something with the modem.  Using a pc or laptop connected to the router, with that address logs, you into the modem.

[DE_]

Thanks!  

Might as well ask, I am guessing the wifi is disabled ? (NP just wondering)  I presume all 4 ports on switch have the public address (as opposed to one specific port) ?

[Datalink]

All of the router, wifi, firewall, port forwarding functions, etc, etc, are disabled in Bridge mode.  The modem runs as a modem only.   I use the bottom port, but I don't think that it matters.  Fwiw, you should be able to get two IP addresses from the modem when its running in Bridge mode, ie, two devices, 2 routers, or maybe router and pc, etc, etc.  @RogersMoin has previously indicated that this can lead to stability issues with the modem, but, I haven't seen any comments from anyone indicating problems were seen when this was done.

[jimboden]

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@Datalink wrote:

Log into the modem, navigate to the BASIC.... GATEWAY FUNCTION, and disable the Residential Gateway Function.  Save the setting and the modem will reboot into Bridge mode where it acts as a modem only.  Your router will have to everything, firewall, routing, port forwarding, etc, etc.

When the router is up and running, if you ever need to log back into the modem to check the signal levels or change the modem back to Gateway mode, you can use 192.168.100.1, thru the router, to log into the modem.  With that address, you don't have to rip your network apart and connect to the modem directly to do something with the modem.  Using a pc or laptop connected to the router, with that address logs, you into the modem.

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@Datalink

This is off topic, but I was wondering if all devices in the CGN3 family are supposed to work with 192.168.100.1? I just tried logging in to my CGN3 and, as usual after bridging, it does not work. Some time back there was a firmware update which disabled the ability to log in, and it was supposed at the time that Rogers would fix the problem.

[Datalink]

Yup, its anyone's guess as to when that capability will be restored to the CGN3.  I don't know if the CGN3AC ever had that capability.