dial in and async dial backup

[fnbt]

I am working on a dial solution using a 3640 w/mica modems and two ISDN PRIs coming into the router. We are wanting to use the same set of modems and lines for both dial in, and async dial backup for our routers. I am having some trouble finding a way to accomplish this, does anyone have any thoughts?

[mljohnson]

The first question concerns how to do the backup; there is some info here that may help you:

http://www.cisco.com/warp/customer/123/backup-main.html

What is not included in the URL above is HSRP, which can also be used for backup by tracking

the serial interface that you want to backup. And of these except the "backup interface" option can be used across multiple platforms.

The second issue is one of dialing and DDR; configuring a vanilla DDR config should be sufficient to get this working, and to still allow for incoming calls.

[fnbt]

I can get my dial backup to dial in to the disaster router now and I can ping the ethernet int on the disaster router, but I can't ping anything beyond that. Anyone have any ideas?

[velimirmkd]

You'll have to add route on the disaster router to "tell it where to look for you", what is probably happening now is that the packets get to the destinaton but they dont know their way back, that is why you can't ping outside. You can also use some routing protocol, but be carefull with that

Here is a link that will help you with the backup solution

http://www.cisco.com/warp/public/793/access_dial/pri_dialin_6435.html

and this one

http://www.cisco.com/warp/public/793/access_dial/1.html

Hope this helps

Velimir