Failover Question

[dh1127]

Hey folks ... I've got a failover question for everyone. I have a hub/spoke WAN with 7 remote sites, all PTP T1's. The core has a 3700 router behind a PIX515, the remotes are all 1721's. I need a failover path incase of T1 outtage.

Is it possible to run a DSL line into the remotes, then have the router automagically start a VPN tunnel to the core router through the Internet incase a T1 dies?

If i'm smoking crack by thinking this will work, let me know and suggest another path.

Thanks

[rkariyanna]

It can be done by using loop back address as the peer address when configuring cryptomaps.

Thanks

Raga

[vcjones]

It can be done quite easily. Detecting loss of a T1 is trivial as long as you enable keepalives. Then use a floating static route to select the VPN path when needed. Alternatively, keep the VPN connection up 24x7, use a routing protocol on both T1 and VPN, and give the T1 a better metric.

Either way, make sure you regularly test the VPN functionality. Otherwise, the better your T1s, the more likely you'll find the DSL dead when you finally need it.

Good luck and have fun!

Vincent C Jones

www.networkingunlimited.com