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From: vjs@rhyolite.wpd.sgi.com (Vernon Schryver)
Newsgroups: comp.sys.sgi
Subject: Re: fsck
Summary: timed(1m) works
Message-ID: <44418@sgi.sgi.com>
Date: 10 Nov 89 02:15:45 GMT
References: <89313.153421W0L@PSUVM.BITNET>
Sender: vjs@rhyolite.wpd.sgi.com
Organization: Silicon Graphics, Inc., Mountain View, CA
Lines: 30

In article <89313.153421W0L@PSUVM.BITNET>, W0L@PSUVM.BITNET (Bill Lasher) writes:
> ... Part of
> the problem is that the time on each machine is not exactly the same (a
> diference of a couple of minutes).  We are going to set all machines to
> the same time...

Timed(1m) or timeslave(1m) can be used to synchronize time on the
machines.  In a simple network (i.e. without gateways separating machines),
just turning it on should be enough to keep time synchronized to within
75msec.

The next release after 3.2 will have improvements to the deamons and the
kernel which should allow timed or timeslave to keep time 10 or more times
tighter.

Time-skew of seconds, not to mention minutes, is a royal pain for make(1)
combined with NFS.

It should be noted that the 4.3 BSD release of timed left something to be
desired in both implementation and protocol.  The implementation in the
newer "network" release may be better, although the protocol, having been
released, is unfixable.  The IRIX version is heavily hacked from the 4.3
release, and seems to servicable.  It's been about a year since time went
crazy among the thousands of IRIS's in the SGI network for reasons other
than operator error.


Vernon Schryver
Silicon Graphics
vjs@sgi.com