Weird traceroute problem

[Christopher Smith]

On Thursday, April 3, 2003, at 06:47  PM, Toni Schmidbauer wrote:

> On Thu, Apr 03, 2003 at 03:08:52PM +1000, Christopher Smith wrote:
>> I have two firewalls - the second is being prepped to replace the
>> first.  All networking from the second machine appears to be fine
>> *except* traceroute looks broken.  This happens:
>
> could it be that your second maschine blocks all incoming icmp
> traffic? so the traceroute udp packets are leaving your network but
> the time exceeded or port unreachable icmp packets coming back are
> blocked?

There are no rules on the second machine yet.

 From a tcpdump, it appears there are no icmp messages being returned by 
the routers.  However, I don't understand why this only happens to this 
one machine - both the other firewall and the target host can 
traceroute through the same routers fine...

Is there some weird bug in 4.8 that affects whether or not icmp 
messages are received ?

-- 
+- Christopher Smith, Systems Administrator 
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|  Server & Security Group, Information Technology Services             
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|  The University of Queensland, Brisbane, Australia, 4072              
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