Needing to create a ISDN backup link to the internet

[admin_2]

I currently have a Leased line for the internet that connects to my 2621 Router by RJ45 which is managed by the ISP! I am wanting to implement a backup ISDN route to the internet incase the leased line goes down. I do not have a static IP with the ISDN dialup account. Does anybody know if this is possible, and if they do what the best config would be or and suggestion would be much appreciated

[dbellazetin]

Yes you can do this. You can use this link as a reference.

http://www.cisco.com/warp/public/793/access_dial/hdlc_12497.html

In your case you will a few changes. On your BRI and Dialer interface do not configure "ppp authentication chap" or "ppp authentication pap". On your dialer interface do not configure the "dialer remote-name" command. On your dialer interface configure the following commands, "ppp chap host (username)", "ppp chap pass (password)", ppp pap sent-username (username) pass (password)", and "ip address negotiated". The floating static route will be "ip route 0.0.0.0 0.0.0.0 dialer0 10".

Daniel

[#3]

Thanks will give it a go