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New Member

ISDN Backup Link

We have 3 sites connected using a managed firewall/VPN solution.

This is a full mesh setup where Site A,B and C have redundant routes.

The ISP we have a contract with has persistant quality issues at Site A.

We need to have A and B in constant communication due to an ERP application that is time and delay sensitive.

We want to setup 3 Cisco 2600's and implement an ISDN backup link that will initiate a connection when any one of the VPN connections/interfaces goes down.

We plan on creating 2 interfaces per router. One pointing to the default route on the VPN device, the second will be the backup ISDN interface configured to dial another sites ISDN link.

Problem: The provider we are currently using will not enable dynamic routing

for devices not in their cloud unless we pay them $$$.

How can we configure the backup ISDN links to initialze if any of the VPN links go down?

Thanks in advance for any assistence.

New Member

Re: ISDN Backup Link

As you have told, you can have 2 interfaces per router.One is the main inteface whis is the VPn inteface and the backup interface is the ISDN interface.

You can give the following commands:


backup interface < secondary interface>

backup delay

Instaed of dynamic routing you can give the static route.

Hope this will help.

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