Conference turris::digital_unix

8574.0. "tar fails to read from TZ88-HSZ40" by BPSOF::POLGAR () Fri Jan 24 1997 08:22

Hello,

A customer has an Alphaserver 4100 FW V3.7 with KZPSA P01 A10 with TZ88
connected to HSZ40 HSOF V2.7. With Unix 3.2G everything worked OK.
When they upgraded to UNIX V4.0A, TZ88 didn't work correctly anymore. They can
write to this tape with tar, but reading or restoring fails at the very
beginning with I/O error. All other utilities (mt, vdump, vrestore, od, cat)
run correctly. The same tape drive works OK when connected directly to a KZPAA.
As tar fails, an errlog entry "Illegal request or CDB parameter" is logged.
Drive is recognized by O/S as TZ88, SCSI ID 0, LUN 5.

The funny is that they can dd tar set from tape to disk and then restore it!

We haven't got a configuration here to reproduce in-house and customer's site
is abroad so help me, please, why tar can't read its own archive?

Regards,

Imre POLGAR

It's a tar bug.  I think a QAR is already logged, but I'm not
really sure.  You should log a formal problem report if you
want a formal answer.

tar is attempting to read a record over 64k (that is illegal
on a tape behing an HSZ40).

	Fred

Helllo,


we have exactly the same Problem.
A.S.4100;HSZ40 Ver. 2.7 TZ887 tar -t forced I/O error.

vdump and dump works fine. HSZOF Ver. 3.0-2 has the same Problem.
Our workaround : TZ887 works direct connectedto the local SCSI-Bus
 without problem, tar -t no errors.

Q: The customer will use Net Save and Restore SW with TZ887,does NSR using tar
?
Q: Is the problem fixed in DEC UNIX Ver.4.0 B ?


Regards 

Ralf 

[Posted by WWW Notes gateway]

	NetWorker (aka NSR) does not use tar, it uses a specific format
	that allows multiplexing save streams on to a single tape
	for performance.  The current product always writes 32kb blocks.