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Can ping but not tracert

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Feenix

IS-IT--Management
Nov 29, 2003
2
GB
Interesting problem.

I can talk to the net no problem, connect fine to all except one particular server. I can ping it, but I can't tracert to it. Additionally, others can connect to a server I host, except this one guy.

The trace route times out at the first hop, & upping the number of hops doesn't help.

What gives folks?
 
The "ping" command uses ICMP packets.

Some traceroute programs use UDP packets on port 33434 and adds one to the port number for each hop (so it can tell which ones are timing out).

Firewalls may block either at intervening hosts for packets addressedto them directly.

For example, a packet goes from A to B to C. Host B blocks packets addressed directly to B, but allows packets destined for C to flow freely through it. Thus, C responds, but B does not.

This may be your problem.
 
Just to make things more interesting, I've found that I can ping/trace etc fine from another dsl line I have to the offending host, just not from this one.
My ISP will be doing a dump (;)) tomorrow to try to track the problem down.
 
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