Path: utzoo!utgpu!water!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!mailrus!ames!umd5!mimsy!chris
From: chris@mimsy.UUCP (Chris Torek)
Newsgroups: comp.unix.wizards
Subject: Re: another question about dump & restore
Message-ID: <12166@mimsy.UUCP>
Date: 27 Jun 88 17:15:57 GMT
References: <5757@umn-cs.cs.umn.edu> <8158@ncoast.UUCP>
Organization: U of Maryland, Dept. of Computer Science, Coll. Pk., MD 20742
Lines: 19

In article <8158@ncoast.UUCP> allbery@ncoast.UUCP (Brandon S. Allbery) writes:
>A file system is active if it's mounted.

Most people consider it active iff it is being written.

>It *is* possible to dump a mounted file system if you sync beforehand
>and make absolutely *certain* that nobody does *anything* on the
>filesystem -- even "echo /being-dumped/*" can screw things up, as the
>st_atime of the directory /being-dumped will be updated.

This is rather minor---you either get the old atime or the new atime,
since the atime does not cross a disk block boundary (assuming 512
byte sectors, or multiples thereof).

You can also dump a file system that is mounted read-only.  This is
often suitable for NFS servers.
-- 
In-Real-Life: Chris Torek, Univ of MD Comp Sci Dept (+1 301 454 7163)
Domain:	chris@mimsy.umd.edu	Path:	uunet!mimsy!chris