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Example config for 831 behind ISP router

Hello,

I need to install a Cisco 831 ethernet router behind an Alcatel VOIP router. Because of ISP restrictions on the VOIP part, I have to use the Alcatel box, and need to place the Cisco behind that to enable use of VPN connections. (currently we use a Cisco 836 with built in ADSL modem).

We have been trying to get this to work in a test environment, but until now to no avail.

A short layout of what we need:

Internet | | Public interface with public IP Alcatel VOIP Router LAN interface (192.168.1.1) | | E1 interface (192.168.1.254) Cisco 831 E0 interface (10.0.1.254) | | LAN

Using this setup, without having set any restrictions on traffic, we are unable to ping beyond the LAN interface of the Alcatel coming from the Internet side (using a lab so not actual internet), and not beyond the E1 interface coming from the LAN.

Does anyone have a sample config of a setup like this i could take a look at?

Thanks in advance,

Erwin Drager

Reply to
Erwin Drager
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You can take a look at a cisco 2611 router configuration that i use (see my different last posts). The situation where i use it is similary as yours. Good luck Sam

Reply to
sam

So does the Alcatel have a route to the 10.x.x.x network?

Chris.

Reply to
Chris

Thanks Sam, will take a look at your config.

Reply to
Erwin Drager

Notice that i have a problem with that config : when the isp change the Internet IP (by dhcp) , the c2611 does'nt see the changement (and the connectivity to internet is lost). And i don't know how to solve the problem ... (see my post IP address by dhcp on a cisco2611... I hope you don't have this pb)

Reply to
sam

It didnt, and that was part of the solution!

I was finally able to solve everything but one issue today (more about that in a new post ;-)

Erwin

Reply to
Erwin Drager

We dont have that problem since our ISP assigns fixed IP adresses :-)

Erwin

Reply to
Erwin Drager

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