Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!watmath!clyde!caip!nike!ucbcad!ucbvax!CITHEX.CALTECH.EDU!carl From: carl@CITHEX.CALTECH.EDU (Carl J Lydick) Newsgroups: mod.computers.vax Subject: Re: BACKUP tape problem Message-ID: <860815143530.04a@CitHex.Caltech.Edu> Date: Fri, 15-Aug-86 17:35:49 EDT Article-I.D.: CitHex.860815143530.04a Posted: Fri Aug 15 17:35:49 1986 Date-Received: Sun, 17-Aug-86 09:39:24 EDT Sender: daemon@ucbvax.BERKELEY.EDU Organization: The ARPA Internet Lines: 27 Approved: info-vax@sri-kl.arpa X-ST-Status: N Topic: infovax, Entry # 3252 Message-Id: <8608090431.AA06268@csvax.caltech.edu> Date: Fri, 8-AUG-1986 13:15 EST From: Daniel B Dobkin To: Subject: BACKUP tape problem > We have a rather serious problem here that I hope someone will be able to > help us with: we've just discovered that many of our weekly save tapes are > unreadable by Backup, although Backup wrote them just fine. BACKUP DOES initialize each tape in the saveset. Sometimes it initializes them WRONG. The following is, of course, only a guess, but it's the only explanation for your problem that I can think of that doesn't involve your version of backup doing something that I've never heard of it doing: Backup is known to select the wrong density for tapes other than the first in a saveset unless the default density for the drive is the density at which you're writing the tape. Given this fact, it seems possible that what's happened to you is that the tape drive was set to allow software- selectable densities, no /density qualifier was used in the mount command, a /density qualifier was used in the BACKUP command, and the density specified was not the drive's default density. In this case the first tape would be written at the density selected in the backup command, and all subsequent volumes would be written at the drives default density. If, whe you tried to read the tapes, software-selection if density were disabled, only the first tape would be readable.