ISDN backup for point-to-point Leased Line

[Shobith K]

hi,

i have a situation where we have a point to point leased line which uses static routes between cisco routers. Now i want to set up an ISDN backup for this setup. So when the serial fails the ISDN should dial to the remote router and establish connection. Can any one help me in this. Any sample configurations for this...

[Kevin Dorrell]

There are two ways you can do this: with floating static routes, or as a backup interface. Here are some documents:

http://www.cisco.com/pcgi-bin/Support/browse/psp_view.pl?p=Technologies:ISDN&viewall=true

http://www.cisco.com/en/US/tech/tk801/tk133/technologies_configuration_example09186a008009455d.shtml

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

http://www.cisco.com/en/US/tech/tk713/tk237/technologies_configuration_example09186a00800a3b77.shtml

Kevin Dorrell

Luxembourg

[dataline]

You can acieve this by giving higher metric to route thru BRI interface (floating static routes) OR by configuring Backup interface.

[ep]

I am doing the same thing currently and will be trying to implement a similar plan this Thurs. So far this is what I think will work best.

Using the configuration that follows, BRI 0 is activated only when serial interface 1/0 (the primary line) goes down. The backup delay command configures the backup connection to activate 30 seconds after serial interface 0 goes down and to remain activated for 60 seconds after the serial interface 1/0 comes up:

interface serial 1/0

ip address 172.20.1.4 255.255.255.0

backup interface bri 2/0

backup delay 30 60

Once the bri is configured, you should set it as the backup to the serial interface.

How did you do your ip addressing on the serial interface?