Newsgroups: comp.unix.admin
Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!think.com!ames!sparkyfs.erg.sri.com!zwicky
From: zwicky@erg.sri.com (Elizabeth Zwicky)
Subject: Re: SUMMARY: Backup while in multi-user mode
Message-ID: <1991May20.204327.17694@erg.sri.com>
Sender: news@erg.sri.com
Organization: SRI International, Menlo Park, CA
References: <1991May20.123129.14433@forwiss.uni-passau.de>
Date: Mon, 20 May 91 20:43:27 GMT

In article <1991May20.123129.14433@forwiss.uni-passau.de> baier@unipas.fmi.uni-passau.de (Joern Baier) writes:
>Nearly everyone who answered pointed out that at his site the backups are
>run while in multi-user mode  but nobody has already observed a serious error
>as a result of this policy.

Sometimes I feel that I'm doomed to spend my life repeating this, but
here goes:

Yes, it does cause problems, I have seen it do so with my very own
eyes more than once. Depending on the version of dump you are running,
these problems range from files that are not on the tape to unusable
tapes. Most people do very few restores; many of the people who have
never had a problem have never done a full restore, either. 

I have seen files come up missing; I have also seen someone do a full
restore on a filesystem which fsck then deleted. If you cannot risk
having a backup be bad, don't do it in multi-user. You can probably
risk having your daily backups be bad. You probably can't risk all
your backups. This is why many of us do some backups in multi-user and
some in single-user. 

	Elizabeth Zwicky
	zwicky@erg.sri.com
