Re: Find a firewall in a network path

[Ansgar -59cobalt- Wiechers <bugtraq () planetcobalt net>]

On 2008-01-20 Lorenzo Capanna wrote:
> The port 21 is filtered from network A to host B.
> Port 21 is not generally filtered from network A ( I'm able to connect
> to hosts different than B ).
> Port 21 is not generally filtered in the host B. ( From networks
> different than A I'm able to connect to B)
> Port 80 is not filtered from network A to host B.
>
> It seems that a firewall is blocking port 21 connection from network A
> to host B.
> The admins of the network A gateway and of the B host deny the
> firewall rule presence.
>
> Is there a way to identify the firewall in the network path from A to B?

tcptraceroute might do the trick.

Regards
Ansgar Wiechers
-- 
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