Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!swrinde!zaphod.mps.ohio-state.edu!pacific.mps.ohio-state.edu!verber From: verber@pacific.mps.ohio-state.edu (Mark Verber) Newsgroups: comp.unix.admin Subject: Re: Why idle backups?? (was Re: Looking for shell script for backup on BSD 4.3) Message-ID: Date: 23 Oct 90 14:36:29 GMT References: <547@fciva.FRANKLIN.COM> <1642@sirius.ucs.adelaide.edu.au> <3955@awdprime.UUCP> <1990Oct23.101621@sasun1.epfl.ch> Sender: news@pacific.mps.ohio-state.edu Organization: Ohio State University; Physics Department Lines: 21 In-reply-to: brossard@sasun1.epfl.ch's message of 23 Oct 90 09:16:21 GMT > In theory, there is a risk if directory affecting operation > are done just at the wrong time (between passes of dump), but in > practice I have never heard of an actual problem occuring. If you > can't take that small/really tiny risk then go to single user mode. > Otherwise, in practice, you most probably will never see a failure, > especially if you do your dump overnight. I have in practice seen a dump corrupted when run on an active file system. I will admit that I have only seen this happen only once over a 10 year period. But if that one time failure has something critical on it you do not forget the experience of having users out for your blood. I certainly never intend to repeat that experience. My policy has been to run incremental backups on a active file system late at night (to exebyte's from cron), but when I do level 0 dumps I drop to single user. This is pretty painless for me since those things that I regularly dump at level 0 will fit on a single exebyte tape so I have my servers shut themselves down automatically in the middle of the night, run dump, and then come back again to multi-user mode. Cheers, Mark