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Cisco router with multiple paths non BGP & failover mode

I have an odd setup. I have a Cisco router with a T1 connected to it, and Ethernet 100 doing routing. I've added a 54Mb/s line of site long haul network extender. This extends my logical network all the way out to the Cisco router. So now the router has FA1 plugged into this long haul device with a network on my local LAN. I've setup the VLAN and routing so that traffic flows from Fast Ethernet 0 to Fast Ethernet 1 with no metric, and then through the T1 as a higher metric. I've configured my router at my main facility to route to the remote logical network via the IP address of the router (on my LAN) at the remote site.

I can unplug the T1 and verify that traffic is flowing now through the new long haul device.

The problem is that when I unplug the long haul device at my main LAN, the routers do not do dead gateway detection and fail over to the T1.

I believe this has something to do with my LAN network actually being on the remote router on Fast Ethernet 1 and the remote router not realizing that this link to the LAN network is actually down.

Is there some way to make this fail over work? I'm not thinking of any solutions.

Thank you;

Edwin.

Reply to
edavid3001
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it sounds like you have the WAN link part of the same subnet as the LAN at 1 or both sites?

the "standard" fix for your problem is to arrange the WAN links (ie both the Ethernet and the T1) to be routed, then let a routing protocol choose which path to use.

The only simple way out of this which doesnt involve readdressing might be to use HSRP to find the local default gateway, and share it between the 2 routers?

Reply to
stephen

Ok, thank you. Either way, my long haul network needs to be a different network than my LAN & routed. The guy who configured the long haul is not here, and can't recall the password so I can't re- configure them.

We're not even sure we are going to keep the T1 as a backup, we just wanted to have it initially in case the long hauls were not reliable. I'm not certain it's worth the investment to reconfigure all this.

Thank you

Edwin.

Reply to
edavid3001

As you have noticed, the router has no way to detect the long haul is not responding from the other side of the LAN link. If you can't run a routing protocol between the long-haul box and your router (the easy solution), you could use "ping based routing" to detect problems and switch over to the T1. A simple search should get you plenty of examples.

Good luck and have fun!

Reply to
Vincent C Jones

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