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From: daveb@geac.UUCP (Brown)
Newsgroups: comp.unix.questions
Subject: Re: UNIX tape backup utilities ( SysAdmin from UniSolutions Assoc.)
Message-ID: <1447@geac.UUCP>
Date: Tue, 22-Sep-87 11:53:33 EDT
Article-I.D.: geac.1447
Posted: Tue Sep 22 11:53:33 1987
Date-Received: Wed, 23-Sep-87 07:20:22 EDT
References: <153@tijc02.UUCP> <1143@ttidca.TTI.COM> <358@mcdsun.UUCP> <261@dnlunx.UUCP> <4040@cit-vax.Caltech.Edu>
Reply-To: daveb@geac.UUCP (Dave Collier-Brown)
Followup-To: comp.unix.questions
Organization: The little blue rock next to that twinkly star.
Lines: 28

In article <160@tijc02.UUCP>, seb022@tijc02.UUCP (Scott Bemis) writes:
> Why can I afford to verify backup tapes on a VAX using the VMS operating
> system,  but may not have the time nor utilities to verify backup tapes on a VAX
> using the UNIX operating system?

In article <4040@cit-vax.Caltech.Edu> mangler@cit-vax.Caltech.Edu (System Mangler) writes:
>Verifying backup tapes can be done to varying degrees, depending upon
>the resources you're willing to commit:
>[a long list of possible meanings of "verify"]
>Which of these are worth the cost?

  Methinks mangler missed a very popular meaning of verify e: run the
backup again, but this time have the program only compare the contents
of the tape to the files/directory-surrogates it would be writing
normally. This is the usual meaning of "verify" on a commercial OS.

  The price is 
	1) one complete backup's worth of time,
	2) many warnings of the form "tape written correctly but doesn't
match disk" if you're doing a backup on a live system,
	3) you have to get a backup program which *does* verify.

--dave
-- 
 David Collier-Brown.                 {mnetor|yetti|utgpu}!geac!daveb
 Geac Computers International Inc.,   |  Computer Science loses its
 350 Steelcase Road,Markham, Ontario, |  memory (if not its mind)
 CANADA, L3R 1B3 (416) 475-0525 x3279 |  every 6 months.