I have two offices which are linked by a vpn connection using Cisco 857 routers. The broadband connection isn't very reliable, so both offices have had a second broadband line installed (through a different ISP).
Each office now has two cisco routers, both configured with a vpn tunnel to each cisco router in the other office.
In office A, both Cisco routers have an internal IP of 192.168.2.1
In office B, both Cisco routers have an internal IP of 192.168.3.1
Only one router at each office is swithched on at any time. The idea is, should the broadband connection drop in either office, the appropriate router can be switched off, and the other router switched on. It would then establish a vpn connection with whichever VPN tunnel was available.
I have tested this, but it is not working as expected.
Office A can make a successful VPN tunnel to office B when both use router A
When the router at either end is changed, the VPN tunnels cannot be established. However,
Office A can make a successful VPN tunnel to office B when both use router B
Is it possible to achieve this?