[pfSense Support] Strange TCP connection behavior 2.0 RC2 (+3)

Mikael Abrahamsson swmike at swm.pp.se
Tue Jun 28 10:36:02 UTC 2011

On Tue, 28 Jun 2011, Eugen Leitl wrote:

> Even disabling window scaling and setting the window to 16MB makes no 
> difference.

If you disable window scaling, you're limiting it to 64k.

> However, we have tried different hardware (L3 switches, media convertes +
> laptops etc), and the symptoms still persist...

You should dump the traffic and analyse it in Wireshark, then you'll see 
if you have packet loss or not. Most likely you do not, and the reason for 
your problem is TCP setting related (see other posts with links).

Before you start replacing hw you should diagnose what your problem is, if 
you're not losing packets and the delay variation is constant, then it's 
not related to the network. Both of these factors can be seen using the 
built in tools in wireshark (Analyze->Expert info, and Statistics->TCP 
stream graph).

Mikael Abrahamsson    email: swmike at swm.pp.se

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