My Server is not able to trace out some IP addresses .. why? need help!pls

[kattyguti]

For some reason my server is not able to trace out most of the USA IP addresses (it doesn't return anything and the script gives timeout after some time) but it does trace out for IP addresses outside the USA.
This is the code we are trying:
shell_exec('traceroute '.escapeshellarg($ipaddress) )

Anyone know why is it happening?

[viking]

What do you mean by "most"? What do you mean by "USA IP addresses"? (I am sure you made the right checks, but I am puzzled... I don't really understand how many servers did you try and from where).
I think at some remote server screening (such as no answers for some ICMP messages) or a firewall between your host and that server which blocks some ICMP messages. I have such problems because of ISP politics.

[LE] shell_exec('traceroute '[...]) ----> traceroute or tracert? Do you have a program named traceroute on your machine? [/LE]