Automatic switching from BRI0 to BRI1 on Cisco Router 1721

[gzachariou]

Does anyone knows how to configure the Router 1721 to switch automatically from BRI 1(ADSL) to BRI0 (ISDN) in case of ADSL downtime?

[paddyxdoyle]

Assuming you are using dialer profiles you configure the your backup interface command on your primary dialer interface.

So if your primary adsl is dialer 1, and dialer 2 is for ISDN, you add "backup interface dialer 2" on your dialer 1 interface

The following link go's into more details:

http://www.cisco.com/en/US/products/sw/iosswrel/ps1831/products_configuration_guide_chapter09186a00800ca664.html

Rgds

PD