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From: Joe Greco <jgreco@brasil.moneng.mei.com>
Message-Id: <199604032301.RAA00745@brasil.moneng.mei.com>
Subject: Re: SO_KEEPALIVE - New feature patch enclosed.
To: fenner@parc.xerox.com (Bill Fenner)
Date: Wed, 3 Apr 1996 17:01:35 -0600 (CST)
Cc: hackers@freebsd.org
In-Reply-To: <96Apr3.143103pst.177475@crevenia.parc.xerox.com> from "Bill Fenner" at Apr 3, 96 02:30:58 pm
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> While we're on this topic, someone asked in comp.protocols.tcp-ip about tuning 
> the keepalive timer[...]
> [...] 
> We already have net.inet.tcp.{keepidle,keepintvl} but it might be worth 
> thinking about adding the TCP_KEEPALIVE socket option.

Uh, uh, uh, HUH?  Check the message you're replying to, for a patch that
does precisely that.  I created a "net.inet.tcp.keepalive", that if set to a
nonzero value, sets the SO_KEEPALIVE flag on new sockets as they are
created, on a systemwide basis.

I think it's even done almost correctly.

The intended application is ISP's and other sites where large numbers of
session hangs may happen...

> P.S. Is it documented anywhere that net.inet.tcp.{keepidle,keepintvl} are in 
> units of 500ms?  Should it be?

I did not see any such documentation.  My keepalive mod is similarly
undocumented...  I have no idea where to document it.

... Joe

-------------------------------------------------------------------------------
Joe Greco - Systems Administrator			      jgreco@ns.sol.net
Solaria Public Access UNIX - Milwaukee, WI			   414/546-7968