Subject: Re: tape support
From: Corinna Vinschen <[email-masked]>
To: JUAN LUIS GARCIA BUENDIA <[email-masked]>
Cc: [email-masked]
Date: Tue, 09 May 2000 11:00:23 +0200

JUAN LUIS GARCIA BUENDIA wrote:
> 
> Dear Ms. Vinschen
> 
> -------------------------------------------------------------------
> one problem is that the block size cannot be changed
> since the tape unit is not a scsi one. and the mt command
> recognizes it. and this prevents the change of the blocksize.

Your device hasn't the ability to change the blocksize
as it's visible in the `mt status 3' output.

> i have formatted my test tape with ntbackup but
> the error in tar tvf /dev/ct about permissions persists

This should have no influence. Formating via ntbackup
means only that ntbackup writes some header infos to the
tape to be able to recognize the tape later again.

> may be a way to change the blocksize in nt?
> is there another alternative way to do it ?
> what do you think?

Not with your tape device.

> the output of mt that i show is not correct, isn't it?.
> i also think so.

Yes, I don't understand that output. Your tape device is
able to report size and remaining of the inserted tape so
why isn't that reported correctly??? I don't know.

> bash-2.03$ mt -f /dev/ct status 3
> tape capacity    :        0 KB          remaining        :        0 KB
> current block    :        0             write protected  :       no
> 
> cur block size   :     1024
> [...]
> fixed length blks: yes                  fixed partitions :  no
> var length blks  :  no                  select partitions:  no

You see? No variable block size feature. Fixed block size 1024.

> get abs blockaddr: yes                  returns capacity : yes
> get log blockaddr: yes                  returns remaining: yes

And here you can see that the device is able to return tape
size and remaining bytes. 

OK, last chance: Please try the following:

1. Check if you are using tar from the net release
   or the tar from my ftp.franken page. Call `tar --help'.
   If you see "*This* `tar' defaults to '-f- -b20' it's
   the net release tar, '-f/dev/st0 -b20' is my tar.

   There may be a problem with setting blocksize related
   to my tar.

2. Insert the tape, call `mt -f /dev/ct retension'.
   Then call again `mt -f /dev/ct status 2' and see
   if it now reports the block size correctly.
   Then try again `tar cvf /dev/ct ...'
   Try using `mt -f /dev/ct rewind' after inserting
   the tape. Your device seems not to have automatic
   rewind feature.

3. Only if all of the above failed, call

   strace -o tar.out D:/bin/tar cvf /dev/ct SOMEFILE

   assuming that tar is in D:/usr/bin and send me
   (not to the list!) the file tar.out as attachment.
   Please compress it with gzip first.

-- 
Corinna Vinschen
Cygwin Developer
Cygnus Solutions, a Red Hat company

--
Want to unsubscribe from this list?
Send a message to [email-masked]