I know this has to be something simple but I'm not sure what. We have a simple config on our Internet router supplied by our ISP. We had 2 sets of IP's assigned to us...for example, 65.65.65.65/30 (router serial interface IP) and 75.75.75.75/27 for hosts. We have static nats for the 75.75.75.x ip's and a single IP Route command pointing everything out the Serial interface. When we ping the serial interface, it responds fine. When we ping any of the 75 addresses, we get the "TTL Expired in Transit" reply...tracert shows a continuous loop between our serial interface and the next hop to our ISP. But...we can still access whatever is running on the hosts (webserver, VPN, email...etc). What am I missing here? Shouldn't the pings be either timing out or replying depending on our firewall config? And why does the ping expire but port 80, 25..etc. are fine? It's not hurting anything...more of a curiosity question.
- posted
16 years ago