Hi folks,

I've been working for a few days now to get my HP-Colorado 14GB IDE tape drive working under RedHat 9.0. I'm really close, but there's still something amiss.

The ide-scsi emulation module was already loading (thanks to my CD burner), and the sg and st modules are loaded as well.

I can do things like:

% mt -f /dev/st0 rewind
% mt -f /dev/st0 erase

...and these work fine. Also, I have successfully tar'd small files to the tape, and restored them, using:

% tar xvf /dev/st0 mysmallfile

However, when I start doing whole directories of stuff, or large files
(50MB or so), then things fail in a hurry. The failure message shows a nonrecoverable error, and the message string complains about having only transfered "0 out of 10200 bytes".

Since so much is working, it seems like there is some subtle communication problem between the st driver and the tape drive
itself; perhaps something to do with buffering a flow control.

Looking thorugh the man pages for 'mt' there a number of options
pertaining to things like the "write threshold" and various buffering
options. I've tried a number of combinations of these, but still no
joy.

Are there other avenues that people can suggest for where to look for the problem. Or, does this sound like a subtle incompatibility
between the st driver and the HP-Colarado 14GB IDE tape drive that would require code changes to the st driver to overcome?

>>>Joey

I'm posting to keep track of this thread. I'm too cheap to buy a tape drive, but I'd like to know what went wrong.

After you www.google.com/linux search terms: ide-tape HP-Colorado Howto ide-tape--post what went wrong.

Joy!

I got it working last night.

The first day of mucking with the st driver options via mt resulted in the partial level of success that I reported in my first post, but in the process I had made an incorrect conclusion about which st option had actually got it (almost) working.

So,...last night I repeated my experiments, but being a bit more methodical this time. It turns out that the magic trick was simply to increase the sttimeout and stlongtimeout options. I had increased these to what I had thought were quit e generous amounts, but apparently not big enough.

After that, I did a bit more tweaking on st options to get the tape streaming properly. Then I installed arkeia (www.arkeia.com) and things have been going great.

The specific commands to get the HP-COLORADO 14GB drive working correctly are as follows:

% mt -f /dev/st0 stoptions write-buffer read-ahead
% mt -f /dev/st0 sttimeout 15
% mt -f /dev/st0 stlongtimeout 30

I'm not sure why the drive needs such long timeouts in order to work correctly, but after doing this, it seems to work like a champ. Note that I had the timeouts set to 6 and 10 seconds previously, and that was only enough to get the drive mostly working. I still got I/O errors on large files.

Turning on write-buffer and read-ahead stoptions got the tape streaming properly. Now I can use tar and arkeia, so far so good!

>>>Joey


This is what I have

Extremely cool.

Hey looks good worked for me now where do i put these files to make em stick on each reboot also i think you have a mis speellgin should be buffer-writes...also what is the diff bewtween stoptions and stsetoptions??

Z

Here's what I put in /etc/rc.d/rc.local

(You were right about the typo, "buffer-writes" is the way to go.)

# Modify the tape parameters so the silly hp-14gb tape works
mt sttimeout 15
mt stlongtimeout 30
mt stoptions buffer-writes read-ahead


Having this in rc.local causes it to execute every time the system boots.

I hope that helps...

>>>Joey

Yeah i got it now although i set my timeout to 3000 and 9000 basically, retensioning the tape was timimg out so i went with higher numbers.

Also the actual command that was fixing my Sense error was the no-blklimit command

Z