Wireshark-users: Re: [Wireshark-users] SMB problems when ICMP is blocked?

From: Jens Link <jenslink@xxxxxxx>
Date: Sat, 06 Mar 2010 18:08:50 +0100
Andrew Hood <ajhood@xxxxxxxxx> writes:


> Solved on Windows by forcing the MTU to 1492. This is a global setting
> for all interfaces.

Manually changing the MTU might lead to other problems. An how low to you
want to the MTU? There might be tunnels, etc. involved which might lower
the MTU even further.

> Doing it the right way and having security allow the MTU exceeded? Not a
> hope in hades. Paranoia rules.

Only Idi^w clueless people drop ICMP completely. It breaks TCP. Yes you
can fix around this problems but doing so will most probably cause other

I hope these people will also block ICMPv6 completely as well. This way 
they'll have no connectivity at thus will cause no problems for the rest
of the world.



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