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Point to Point T1 with VPN loadbalance/failover using 2811 router


I would appreciate if anyone can give a look at my routers design/configuration and let me know what is missing and what can be done to optimize the configuration(see attached config files). I have two sites that need to be connected site A which is our main branch where I’m located and site B where the new/next router is located. We bought two used Cisco 2811 with a WIC-1DSU-T1-V2 cards installed on each one of them. We have connected A to B through Point to Point T1 and at both sites we have T1 and Comcast connection to Internet. Moreover, I’m thinking to backup the P2P connection utilizing existing Internet connections using VPN or even if possible for load balancing.

For the phase one, I have stared the T1 configuration and so far I think I have gotten the P2P T1 kind of up and running. But there is a problem, I can ping all the interfaces from site A to site B and vs. versa. But can’t go anywhere beyond the internal interface of the router on site A, I can’t even ping the internal interface of the router. I have attached both routers configuration to this message please give a look and let me know what is causing the problem.

Any comment greatly appreciated,


Site A

10.31.1.x subnet

Site B

192.168.45.x Subnet

Fast Ethernet 0/0

connected to

local LAN

Fast Ethernet 0/1

Connected directly

to WAN

Serial Interface 0/0/0

Connected to T1

Smart Jack



how are you recieving routes from the internet, i think you shoud have default routes pointing to the ISP router.

you have static defaults pointing to your internal LAN interface in config..? what are these routes used for..

Also why is ip nat enable needed, as i dont see any other NAT config in the router..

in order to configure internet as a backup start with GRE tunnels.

for ex

int tun 0

tunnel mode gre

tunnel destination 

tunnel source

ip add x.x.x.x y.y.y.y

do this for both sites,

then add static route for the destination subnets pointing to both the T1 and the tunnel interface

give it a try..and let us know