Routing, Traceroute, who's up for a challenge?
Posted on 2004-04-16
Let's say your internal subnet is 18.104.22.168, your default gateway to the Internet is 22.214.171.124. You seem to be able to run a trace to every other subnet in the world that allows it. In particular, 126.96.36.199, you can trace to 188.8.131.52. you can trace to every subnet on 184.108.40.206 but one. When you try and run a trace to 220.127.116.11, the response you get makes it appear that 18.104.22.168 is inside your network. It never seems to hit our gateway 22.214.171.124.
example traceroute 126.96.36.199
replys 188.8.131.52 which is what I expect, my gateway, the first hop.
184.108.40.206 gateway address on the router, this is good, and on to success.
problem child example traceroute 220.127.116.11
replys 18.104.22.168 this is not good.
22.214.171.124 and again repeatedly until it hits 30 hops and stops.
nslookup 126.96.36.199 returns a domain not found.
I can't ping 188.8.131.52, (destination net unreachable) but I can ping the other 184.108.40.206.
I've examined the routing table on the servers and routers we control and find no trace of 220.127.116.11, or 18.104.22.168.
Level 3 manages the router that connects us to the Internet. They say that they can run a trace from the router to 22.214.171.124.
I've added a static route to 126.96.36.199 on the gateway, still no luck.
Who has suggestions on a cause and solution or troubleshooting tips?