Greetings!

Here is my question: is it possible for a malfunctioning (travan)
tape drive to cause even a new tape to have a write error afterward?

Now, some background! :-)

I have a Linux computer, a 450 MHz, Pentium II system purchased in
mid-1999. It had a travan, TR4, tape drive. I had numerous problems with
it, the first three years. (I wound up sending it back, under warranty, a
couple of times.) In 2002, I purchased a new travan tape drive. It is
TR5 instead of TR4, so this led to the purchase of new travan tapes.

This last drive has been pretty good. I don't believe I had many
problems with it, until the last six months to a year.

I started having backups that didn't finish, for one reason or
another. I would purchase brand new travan tapes, and about 30 to 40% of
them would work, and slightly over half didn't even work, on the first
try. I took many Imation tapes back to Office Depot.

About a month ago now, I purchased three more travan tapes from
Certance, which seems to be the company that handles Seagate's tape
business now. I got three new travan tapes. The first one worked. The
second and third one didn't. (Most of the errors are write errors.)

I purchased a travan cleaning cartridge, which arrived the middle of
this past week. I cleaned the tape drive head. Still, now, the second
and third brand new Certance tapes which arrived only a couple of weeks or
so ago, are apparently not usable.

With this many tape problems, I find myself looking for another
possible explanation. At first, I thought that Imation must have had a
bad batch of tapes, because only two or three of the six or seven I
purchased worked. Now, three new tapes, different brand, from Seagate (or
the company who handles their tape business now), still one worked, two
didn't.

If I didn't have any backups to work, I would look into hardware.
But, a backup will work every once in a while. And, I verify it, reading
through it again. Not an error. Although not frequently, I have restored
some files from a backup before. It worked fine.

But, it's like, once a tape has an error, that tape is not usable
again. And, I have tried up to five times to write on a tape which had an
error, and it always fails, at about the same point in the backup,
afterward.

At first, I just returned the tapes to Office Depot, and they
replaced them (on two or three different trips). But, it got to the point
where even the once again new tape, just unwrapped, failed.

I have to consider, is there possibly a hardware problem with my tape
drive? I do not understand it 100%, but I could see how a malfunctioning
tape drive could "garble" data being written to the tape, such that that
tape is not readable. But, I would think, in this case, just rewriting
over the tape would have the tape still usable. These are write errors,
and they always fail at the same point in future backup attempts.

At the moment, I have ONE tape which has worked. (The first of the
three recently purchased ones from Certance.) I am afraid to try to use
it, because if it errors, based on my observations and history, it won't
be usable any more, either.

I am about to upgrade to a newer version of Linux, and get two new,
larger, hard disks. What I'm planning on doing is shut down the current,
older, Linux, and go into the cabinet, and remove the two smaller hard
disks and replace them with larger hard disks I'm about to purchase.
Then, on these new hard disks, install the newer version of Linux. (I
then need to have many very important data files on a good, reliable,
backup, so I can restore the data files, with all new operating system
files already in place.)

I would only feel comfortable doing this after I have at least TWO,
known, good, reliable backups, from which I can get my data files. (Once
I get them on the new Linux system, and back them up then [and I'll be
using a different backup scheme, also as of the new Linux system], I'll
have them on the hard disks, and on backups of the new system, and I'll
feel more comfortable that I have them enough different places to restore
them, should something happen.) But, at the rate I'm going, getting at
least two known good backups is becoming increasingly difficult, as well
as expensive! :-O

So, there is some background information. Thank you for sticking
with me and reading this far, if you're still reading! :-D

If anyone has any revealing information, suggestions,
recommendations, etc., I'd be quite pleased to hear (or read) them! :-)

Thank you!

Barry
--
Barry L. Bond | http://home.cfl.rr.com/os9barry/
Software Engineer, ITT Industries | (My personal home web page, last

"Barry L. Bond" <barry (AT) barrycon (DOT) cfl.rr.com> wrote


With so many tapes failing, to my mind there are three possible causes.
1) The tape drive is writing very marginal records, which only pass on an
above average, or perfect tapes.
2) You don't mention how old your distro is, or whether you've looked into
an updated driver. The situation of the same tape failing at the same point
suggests a bad spot which causes an unrecoverable error. The drive's error
recovery routine may be suspect. I doubt that any manufacturer guarantees
their product is totally perfect.
3) A combination of the above.

Allan

Hi Allan!

I last installed Red Hat Linux 7.1, in September of 2001. And, I
have updated several things independently of Red Hat. (I am still running
the 2.4.17 kernel, which I wound up having to get from www.kernel.org to
compile, but I have remade my kernel a few times over the last almost four
years. I installed CUPS in 2003, etc.)

Well, I haven't looked into an updated driver. The driver is the one
I've been using since September, 2001, and it's always worked perfectly,
with my two SCSI hard disks, and the one SCSI tape drive, until the last
few months, regarding the tape drive, only.

If the tape drive is writing only marginal records, that would be a
problem with the tape drive, correct? (I just want to be sure I
understand you.)

That could explain the situation I've had. Except, the fact that it
works on some tapes, and, once a tape doesn't work, it REALLY doesn't work
-- ever again. I'd think that if the drive was writing only marginal
records, the next write would (at least possibly) be readable/good....?

Thank you, Allan!

Barry
--
Barry L. Bond | http://home.cfl.rr.com/os9barry/
Software Engineer, ITT Industries | (My personal home web page, last

"Barry L. Bond" <barry (AT) barrycon (DOT) cfl.rr.com> wrote

Yes.

My only experience with tapes is on mainframes (except my first home-built
Nascom, which used a cassette recorder as input/output at 110 baud!)
Sometimes a tape would get stretched, which could cause a ripple, which
would always give a write error, except that decent error recovery would
skip a bad spot. That would only be discovered during writing by a
read-after-write head, when the record could be rewritten, otherwise only
when the tape came to be read. I have absolutely no idea about Travan
drives specs.

Could you sacrifice a tape to examine it at the failure spot? Could be an
oxide defect, too.

Another possibility is a dirty head. Could you get at it with a baby-bud
and alcohol? A dirty head, built up over time, could certainly account for
marginal writing, which could cause grief if the tape wasn't quite 100% at
a particular point.

Good luck

Allan

On Sat, 25 Jun 2005 23:07:27 GMT, barry (AT) barrycon (DOT) cfl.rr.com (Barry L.
Bond) wrote:

bare fingers) for signs of damage:
1) look at the edges for feathered or wavey edges that are a sign of
passing thru a drive with guide or other tape path mechanical
alignment problems.

2)Look at the flat surface at a angle for pits (dimples) caused by
dirt on the guides or drum.

3)lookk for wrinkles or creasees. a sign that the hub drive (Forward
or reverse) may have problems OR the tape stuck to the drum either
from condensation (bringing a cold drive into a warm room and not
waiting for it to wame up and dry out (been there)) or gummy residue.
, _
, | \ MKA: Steve Urbach
, | )erek No JUNK in my email please
, ____|_/ragonsclaw dragonsclawJUNK (AT) JUNKmindspring (DOT) com
, / / / Running United Devices "Cure For Cancer" Project 24/7 Have you helped? http://www.grid.org

On Sat, 25 Jun 2005 23:48:31 GMT, Steve Urbach
<dragonsclaw (AT) NOTmindspring (DOT) com> wrote:

drum.
, _
, | \ MKA: Steve Urbach
, | )erek No JUNK in my email please
, ____|_/ragonsclaw dragonsclawJUNK (AT) JUNKmindspring (DOT) com
, / / / Running United Devices "Cure For Cancer" Project 24/7 Have you helped? http://www.grid.org

Hi Allan!

Ah! Thank you!

I do now truly see how a "not working properly" tape drive (whether
it be a dirty head or some other problem with the strength of the head
manipulating the oxide particles on the tape) could indeed cause a tape to
appear to have a permanent error at about the same point.

Thank you so much! This gives me a couple of ideas to try! :-)

If I could just manage to get at least two good backups of my data
files before I wind up replacing the hard disks and installing a newer
version of Linux (and then having a different backup scheme), I would be
happy! I have a couple of other ideas to try, and one will be to clean
the drive head (differently and possibly better than the cleaning travan
cartridge I purchased).

Thank you again!

Barry
--
Barry L. Bond | http://home.cfl.rr.com/os9barry/
Software Engineer, ITT Industries | (My personal home web page, last

Hi Steve!

Thank you very much. I may indeed look at this.

I'll be trying to determine if the tape drive does possibly have a
problem, and whether getting it repaired will at least assure that I can
use the travan tapes I have to get hopefully, a few, backups before I
completely redo my Linux system!

Thank you again!

Barry
--
Barry L. Bond | http://home.cfl.rr.com/os9barry/
Software Engineer, ITT Industries | (My personal home web page, last

Allan Anderson wrote:
Travan tape drives are about the lowest-end tape you can get and
generally don't have that great a reputation for reliability. I don't
know that they're prone to stretching per se, but retensioning them
regularly is recommended. Under Linux 'mt retension' does the job and
sounds like a similar sort of situation.

Barry L. Bond wrote:
problems, could be writing into the formatting records, causing write
errors and unusable tapes. If your drive came with a formatting tool, it
may also allow you to test the formatting. Reformatting a tape can take
hours, though, and if your drive has speed and/or timing issues, may not
create a usable tape. I have owned several Travan drives, and tapes
often couldn't be written on one and read on another, and I did lose a
number of new tapes to poorly performing drives. I would suggest you
move to another media, if you can.