I have a router with a default gateway at 192.168.3.4. It contains routes to all my private subnets. One of those private subnets also has a gateway to the world via T1. I have built a server that will handle DNS and mail relay in case my primary T! here goes down. It's all rather simple really.

In order to have the secondary mail/dns server function properly I need to be able to route to it's public address from the master router that is 2 hops away. So I merrily palce the following route in the master router:-

ip route aa.bbb.ccc.0 255.255.255.0 192.168.2.10 (an internal router that several other routes point to and function perfectly well).

I write it to memory and ping the box... Bingo. So, I'm happily playing when I get a call from one of my other agencies telling me that they cannot get to a web site that they use frequently. I run an nslookup on it and find it is at aa.ee.ff.gg. The letters that are in this address match the letters in the route I put in so if aa = 10 in the route above then aa = 10 in the nslookup. As you can see the aa network is the only common factor. So I run a tracert on the aa.ee.ff.gg address and my master router tell me that the "destination host is unreachable"....

So I remove the route and everything is peachy except that I, (obviously), can't reach my aa.bbb.ccc.ddd host through the internal network which I need to do. I re-added the route same thing, I checked it for typos - none, I checked to see if there was any possibility of a conflict - none!!!!! But the host is unreachable... In fact _every_ host in the aa network is unreachable.... I have reloaded and done a hard restart and it is still messed up!!!!

Now correct me if I'm wrong but a network aa.bbb.ccc.0 and a subnet mask of 255.255.255.0 is a collection of hosts from aa.bbb.ccc.0 to aa.bbb.ccc.255 and has no relation whatsoever to the network aa.ee.ff.0.

So why the hell will my Cisco not get this right