From owner-freebsd-current  Sat Dec  4 16: 2:19 1999
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From: Frank Mayhar <frank@exit.com>
Message-Id: <199912050001.QAA39637@realtime.exit.com>
Subject: Re: Mounting one FS on more than one system
In-Reply-To: <1082.944351072@dstc.edu.au> from George Michaelson at "Dec 5, 1999 09:44:32 am"
To: ggm@dstc.edu.au (George Michaelson)
Date: Sat, 4 Dec 1999 16:01:52 -0800 (PST)
Cc: mckusick@flamingo.McKusick.COM (Kirk McKusick),
	msmith@FreeBSD.ORG (Mike Smith), match@elen.utah.edu,
	current@FreeBSD.ORG
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Regarding a filesystem mounted on multiple boxes, check out DFS; there's
a spec available from the Open Group in the UK for $58.00:
	http://www.opengroup.org/pubs/catalog.saved/p409.htm

If you allow multiple R/W mounts, it's certainly not trivial.  As Kirk said,
you need a strong coherency mechanism; DFS uses a token mechanism invented,
AFAIK, by Locus Computing Corporation.

I work on the former Locus clustering stuff (for Compaq, these days), so I
can't really contribute, but I know there are white papers and other docs out
there.
-- 
Frank Mayhar frank@exit.com


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