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New Member

Backing up a point to point link w/ a VPN box.

I have two sites connected via PtP link using 3600 series routers. I'm trying to setup a VPN box to backup this line in the event of any interruptions.

Is there a way that I can tell the router(PtP) that if the serial link is down to use a seconday route to get to a destination network? I've tried adding multiple routes to the network w/ different weights, but it doesn't work. I'm not sure if I'm missing anything.

Does anyone have any suggestions.

New Member

Re: Backing up a point to point link w/ a VPN box.

The only way you can make this work is to add weighed static routes that point to the VPN boxes on each side of the link. For example lets assume that the Ethernet address on Ethernet 0 is Lets again assume that we have a point to point serial connection between this router and a remote router. We have elected to use for the Wan addressing. Our routers serial port address is the remote router is The remote routers Ethernet port is So in our local router it will know the following:

Network is directly connected.

Network is via serial 0

We have a couple of ways that we can announce the networks on each routers Ethernet port to each other, via RIP-V2, EIGRP or something else. We could elect to use static routes. So lets take a look:

Local router:

ip route 1

Remote router:

ip route 1

If we look in our routing table “show ip route”. We will see that the static routes have a metric of a 0. The lower the metric the more preferable the route. Lets assume that your VPN boxes on each side were and In the local and remote routers the route might look like this:

Local router:

ip route 150

Remote Router:

ip route 150

The route for will prefer to the serial 0 connection. If the serial port goes away the router will prefer the VPN box.

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