20/40Gb dat drives

[Ayman Altounji]

This problem also applies to ML350 with 20/40 Gb drive and may well be a SCO issue.
When using tar to save I always issue the tape -a 1024 setblk /dev/rStp0 in the backup shell prior to the tar command. The message returned is :
tape:Can't open '/dev/rStp0': Device busy and the tar continues but takes about 10 times longer.
A setblk on its own will then work and the save progresses in the normal time UNLESS the machine is rebooted then the message appears either with the same tape or a brand new tape.
HARDWARE/Drivers:
Server Device Driver Controller
ML350 SDT-10000 cha Ultra 2 onboard
ML370 COMPAQ-10000 ad160 Ultra 3 PCI

Also in SCO5.06 only root can use the tape device because permissions are different to 5.05 - this is resolved by chmod ugo+rw on /dev/rStp0

Any thoughts please would be appreciated.

Clive Rhodes
Jobmaster Plc,UK

[Ayman Altounji]

You need to use a "-b 20" or larger tape block size when using the tar command. The tape drive model you are using has a variable block size. The tape -a command to set the tape block size to 1024 is invalid and is not required for your model of tape drive.

[Ayman Altounji]

Thankyou for the -b suggestion - this works fine.
Clive Rhodes

[Ayman Altounji]

I got the same problem when I use the cpio command too. Do I need to specify any specific switch when I do cpio command. I am using
cpio -ocvdumB /dev/rStp0 command to manual backup the files. But the server happen to be stopped in the middle of cpio process and it returns as internal error. I already ask Compaq to replace my DAT20/40 internal tape drive 3 times. Any thoughts would be helpful.. Kenny Chia