It is currently Sat, 21 Jul 2018 03:08:32 GMT



 
Author Message
 SCSI Tape Device FATAL error on 2.4.10

Kai,

I've managed to get ot the bottom of this problem, and it may be something
to annotate
your code to look for in the future.  The newer Exabyte tape drives have
enabled a
rather clever feature which provides auto-cleaning capability for certain
types of tapes.
The tapes we are using are of this type (unknown to me until we did some
checking).

These 150GB tapes have at one end of the tape a spliced section of cleaning
tape actually
spliced onto the end of the data portion of the tape.  When the drive
detects a media error,
the tape is forwarded or rewound to hit this cleaning portion and srubs the
heads of the
tape drive.   What was happening is our software was assuming this tape
section was valid,
and attempting to write to the cleaning tape portion, which for obvious
reasons, was resulting
in some very interesting errors in Linux 2.4 including a few Oops we were
able to reliably
generate in both the st module and the AIC7XXX driver. :-)

What we are doing now is disabling this feature (if enabled) on the tape
drives, and doing
a more rigorous check of the media to detect which tapes have these cleaning
segments
spliced into the data portion of the tape cassettes.  The SCSI mode page
settings command
do not seem to describe how to disble this from SCSI.  At present, we have
disabled it
on the devices so they do not rewind and retension and autoclean when an
error is detected
on the media.  What's more troublesome is detecting when you are hitting a
cleaning
section of the tape, but we have done a workaround that seems to work.

You may want to annotate this as a feature to deal with at some future date.

Jeff



 Tue, 20 Apr 2004 05:30:15 GMT   
 
   [ 1 post ] 

Similar Threads

1. SCSI Tape Device FATAL error on 2.4.10

2. Error Compiling kernel 2.4.10

3. Network error in 2.4.10

4. Kernel 2.4.10: aironet4500_card.c:62: parse error

5. Help in SCSI Device Driver Development For SCSI DDS Tape drive

6. Fatal server error: Cannot open mouse (Operation not supported by device)

7. Hanging boot when installing Suse 7.3 (Kernel 2.4.10)

8. kernel 2.4.10 comes up as 2.4.5 ???

9. Urgent : PPP fiasco with 2.4.10

10. chat fails on linux 2.4.10


 
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group.
Designed by ST Software