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RE: Strange behavior

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Subject: RE: Strange behavior
From: "Steffen Bisgaard" <steffen_bisgaard@sento.com>
Date: Fri, 23 Feb 2007 15:47:54 +0100
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Thread-topic: Strange behavior
 
This is a nonsense.
Programs bind ports on ip addresses, not on hostnames.
So, if you start a program with a hostname, it resolves and then uses the 
associated ip address.
Telnet clients do the same, they first resolve the hostname into an ip address 
and then connect to it.

All domain-related stuff could only be done at application layer, but the tcp 
connection cannot be blocked (there is no way for the server to know which is 
the hostname typed in the client looking only at the layers from transport to 
link).

So, if you resolve both hostnames in the same ip address, telnet will connect 
to both, or none.

Bye
Fabio





Thought so - thanks for the confirmation.

After a few kicks up a few backsides, our internal DNS servers have now had the 
appropriate MX records added and all is well.

Sorry for wasting everybody's time.

Stef 

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