From owner-freebsd-net@FreeBSD.ORG  Fri May 27 15:16:42 2011
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Date: Fri, 27 May 2011 10:59:59 -0400
From: Tom Worster <fsb@thefsb.org>
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Thread-Topic: Can net.inet.tcp.msl be set per interface?
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Subject: Can net.inet.tcp.msl be set per interface?
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[[I asked this yesterday on -questions, probably the wrong list]]

If a server has one interface to the Internet and another interface to a
switch connecting to a few other servers, it seems TCP's MSL value might
reasonably be set a lot lower on the private interface.

I'm specifically thinking of a lot of short MySQL connections(*) between
the
servers on the private LAN. The average number of MySQL client connections
in TIME_WAIT will be proportional to MSL. And, while the circumstances
under which a long MSL would help anything are unimaginable on the LAN,
they are not on the Internet.

So can net.inet.tcp.msl be set per interface?

(*) Or similar: Sphinx, memcached, perhaps.

Tom