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From: Charles Swiger <cswiger@mac.com>
Date: Tue, 7 Sep 2004 13:13:40 -0400
To: "R. W." <list-freebsd-2004@morbius.sent.com>
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Subject: Re: MTU Blackhole problem?
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On Sep 7, 2004, at 7:46 AM, R. W. wrote:
> I'm guessing that this is a path MTU discovery blackhole, since if I 
> set
> sysctl  net.inet.tcp.sendspace=400  the problem goes away. (I presume
> that net.inet.tcp.path_mtu_discovery: 1  means that path MTU discovery
> is already turned-on by default.)
>
> What the correct way to deal with this? Should I just play around with
> net.inet.tcp.sendspace?

Try "ifconfig en0 mtu 512"; replace en0 with the name of your NIC.

[ Try different MTUs, too. ]

-- 
-Chuck