Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!swrinde!mips!sgi!shinobu!odin!anchor!olson
From: olson@anchor.esd.sgi.com (Dave Olson)
Newsgroups: comp.sys.sgi
Subject: Re: 8mm tape media woes
Message-ID: <1990Sep11.011545.5546@odin.corp.sgi.com>
Date: 11 Sep 90 01:15:45 GMT
References: <9009101958.AA29127@remote.dccs.upenn.edu>
Sender: news@odin.corp.sgi.com (Net News)
Organization: Silicon Graphics, Inc.  Mountain View, CA
Lines: 44

In <9009101958.AA29127@remote.dccs.upenn.edu> YATES@C.CHEM.UPENN.EDU ("Yates, John H.") writes:

| Argh!! I ordered 10 Sony 8mm tapes from INMAC, $13 apiece. Catalog
| misprint I was told, $33 is the real price. They honored the lower
| price for the 10, but had only 5 in stock, backordered the second 5.
| Ok, I told them, but I won't buy any more 8mm from INMAC. Ok, they said.
| 
| The first 5 to come in were: Sony 8mm data cartridge QG-112M.
| The next  5 to come in were: Sony Video 8 P6-120MP (metal particle tape).
| 
| When doing backups, I tend to get roughly 295 recoverable errors on some
| of the tapes of each variety, upon which the system then assumes the end of
| volume (just gives up?), and asks for another tape. Argh! Not good for an
| overnight script. The data DOES all fit on one GOOD tape.
| 
| Questions: 
|            Are the two varieties above of high enough quality?
|            What is the best tape to use? 
|            Should I suspect a hardware problem?
|            Should I suspect dirty heads? (this drive is almost brand new!)
|              (and how should they be cleaned? I know VCR fanatics on both
|               sides of using head cleaner tapes).
| 

Our Exabyte rep has STRONGLY recommended that you do NOT use MP (metal
particle) tape on the Exabyte drives.  You will get far more errors than
you should.  The Q6-112M sounds like it is the same tape that Exabyte
sells (I'm not positive), EXCEPT that the official ones sold by both
Exabyte and Sony are Data grade.  This means that they have been cerified
as reasonably error free, and are otherwise pretty much the same as the
commercial grade.

If you choose not to use Data grade tapes, you are on your own.  They
may (and in fact do) work fine most of the time, but you can't count on
it.

When bru (or other tape programs) give up and ask for a new tape, it is
usually because they have encountered an unrecoverable error.  There
should be a message to this effect on your console and/or in SYSLOG.
--

	Dave Olson

Life would be so much easier if we could just look at the source code.