ISDN Backup to ISP for a Broadband Connection - Sample Guide Needed !

[fkseow]

Hi anyone please help out the following;

I have a Cisco 2610 Router with the following hardware specs;

1x10 Mbps Ethernet Port

1x WIC-1B-S/T ISDN Port

IOS 11.XX

Router is used to connect the Internal LAN to the Internet via a Broadband Link (router is using its Ethernet Port to connect to the Broadband Cable Modem).

If the broadband link is down, the router will fire up the ISDN link to dial to "Another" ISP for Internet Access. (Same as home analog dial up to ISP with a "username" and "Password")

Questions:

Q1. Please help is there any sample configuration guide for such scenerio ? (ISDN backup and dial to another ISP upon the main link fails with a username and password)

Q2. How do I configure the routings (Static routes) for the Broadband Link and the ISDN dial up ?

Q3. Can I use the default Route (0.0.0.0/0) for this case ?

Please help.

Thank you.

[rsissons]

The following URL gives an example of how to configure a backup interface. Although the main interface here is serial, the idea is the same.

http://www.cisco.com/en/US/tech/tk801/tk379/technologies_configuration_example09186a00800b1148.shtml

You can use a floating static route to the 0.0.0.0 network, ie a static route with a high administrative distance, to route over the ISDN.

[fkseow]

Hi rsissons, please guide that how do I configure the routing for the Primary Link and the ISDN dial backup link.

If I were to use the defualt routing for the Primary Link (0.0.0.0/0), so what sort of route(s) should I configure for the ISDN link ?

How do I configure the ISDN link to call to a local ISP as what we try out at home (using analog 56K modem) with an username and password.

Is there any example for these routing and ISP dialin?

Please help .

Thank you.

[mgreenlee]

Another issue that arises in this situation is the status of the ethernet link. Even if the connection to the cable modem is good, the connection from the cable modem to the ISP could drop. Unless you are receiving a route from the cable modem, backup will not work. The backup method would have to be aware of the failure at the cable modem to initiate the ISDN call.