Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!mailrus!wuarchive!zaphod.mps.ohio-state.edu!tut.cis.ohio-state.edu!ucbvax!pasteur!ames!skipper!elxsi!maine From: maine@elxsi.dfrf.nasa.gov (Richard Maine) Newsgroups: comp.binaries.ibm.pc.d Subject: Re: Backups: (was: Formatting 720K disks to 1.44 Megs HELP!!) Message-ID: Date: 1 Dec 89 23:20:03 GMT References: <1989Nov27.212809.7241@ux1.cso.uiuc.edu> <1114@bridge2.ESD.3Com.COM> <89Nov28.223437est.19733@me.utoronto.ca> <408@vlsi.ll.mit.edu> Sender: news@skipper.dfrf.nasa.gov Distribution: na Organization: NASA Dryden, Edwards, Cal. Lines: 36 In-reply-to: malpass@vlsi.ll.mit.edu's message of 30 Nov 89 14:36:39 GMT In article <408@vlsi.ll.mit.edu> malpass@vlsi.ll.mit.edu (Don Malpass) writes: > Fastback-Plus: Have you also used the "Check" or "File Compare" option > (I can't remember the exact name) in the Restore menu on your backup > disks? I just went through this exercise using HD (not 2D!) disks at > 1.44 Megs, and the results were an eye-opener! This was on a Zenith > ... > BACKUP! Sure it takes time, but as has been stated by someone else, if > the backup is bogus, how much good is it. You KNOW the only file which > gets trashed and needs to be restored will be the only one that is sick > on the backup. My "solution", by the way, was to print the CRC's > (Unix-SUM, actually) of all the files that didn't compare and then > re-restore from one of the two backup sets any that looked bad after > the format/restore had been done. I'll probably save BOTH backup sets > for the future. Has anybody else experienced similar problems? Yes, I've experienced virtually the identical problem, and on several different systems. My solution is that I don't use Fastback. For all I know, the backup is actually fine and its just the verify option that is bogus, but frankly I don't care. If the software is that flaky (or drives the hardware hard enough to make it flakey) then I won't trust my backups to it; somebody else's maybe, but not mine. Note that since you get different results on different attempts to restore/check from the same tape, there is nothing you can do to predict or prevent it. Maybe its all fine, but it doesn't leave me with that nice warm feeling of confidence that a just-completed backup is supposed to. This is all on media and drives that work fine with all other software I have tried. I'm not trying anything cute like intentionaly damaging the media (as in Fastback's ads). I don't like its behavior with perfectly good media. -- Richard Maine maine@elxsi.dfrf.nasa.gov [130.134.1.1]