Path: utzoo!attcan!uunet!aplcen!uakari.primate.wisc.edu!zaphod.mps.ohio-state.edu!ncar!husc6!m2c!seqp4!markr
From: markr@seqp4.ORG (Mark Roddy)
Newsgroups: comp.protocols.tcp-ip
Subject: Re: How long before I can reopen a closed socket?
Message-ID: <515@seqp4.UUCP>
Date: 14 Jun 90 18:52:04 GMT
References: <4847@litle.litle.COM>
Organization: Sequoia Systems Inc., Marlboro, Mass.
Lines: 29

In <4847@litle.litle.COM> tom@litle.litle.COM (tom hampton) writes:

[How Long Must I Wait?]

>We have a problem with a socket-based server application which needs to
>restart quickly.  What we find instead is that it may take a minute
>before the passively binding program can reopen a socket after both
>the active and passive binders have terminated.

>2) We are using a "well known address" and these things don't recycle
>   instantly after closing (just a wild guess...)

In fact you must wait:

	CHORUS: Two Times the Maximum Segment Lifetime!

Which is the minute or two you describe.

The solution is to not use the well known address for the connection -
TCP allows you to accept a connection on a different port address than
the destination address in the connection request.

This is the mechanism used by most *nix TCP/IP services. 

The well-known address is always available to service the 
next incoming connection request.
-- 
-Mark Roddy
Sequoia Systems, Inc.          (508) 480-0800 x1284
markr@seqp4.uucp               m2c!seqp4!markr