I'm sure that this is pretty simple, but I want to be able to ping the external address of my cisco 1811 router from outside the network (like from a remote location). any time I try to ping the external ip address now all I get is a request time out. I'm pretty sure this is a simple firewall issue (possibly relating to icmp), but I don't know how to configure that on the firewall. If this can be done via CCP that would be great (or if the CLI commands are simple that would be ok too I guess).
Do you have zone based firewall on the router? Then you would need to inspect icmp from the outside zone to the self zone.
If not, you would need to open the outside interface ACL for icmp to the toeuer ip address.
I hope it helps.