Actually I have the same opinion like you.
In my 1st answer said:
-Multiplexed backups cannot be read by any version of tar
that mean gnu tar or netbackup tar can't read either
In 2nd answer I said:
-gnu tar can't read compressed tape while netbackup tar can.
that mean using gnu tar can't read compressed tape while netbackup tar can
read it.

I am very interested to know on how you do this in detail. Please give me
sample
>It also says that backups that span tapes have to be concatenated to be
read
>with tar.  IOW, you have to use dd to contatenate them to a disk, then use
>tar to read the tar images from tape

I am sorry if I am wrong. I can't argue with netbackup guru like you.

----- Original Message -----
From: "W. Curtis Preston" <curtis-lists AT thestoragegroup DOT com>
To: "'nawir'" <nawir AT esuria.com DOT bn>; <veritas-bu AT jasons DOT us>;
<veritas-bu AT mailman.eng.auburn DOT edu>
Sent: Thursday, February 27, 2003 2:04 PM
Subject: NBU format of tapes written by netbackup


Nawir,

I think you need to re-read that section of the manual.  While I agree it is
poorly formatted, it does not say what you suggest.  What it says is
"Multiplexed backups cannot be read with any version of tar."  That includes
the NetBackup version.  See also the note at the end of pp. 717, which says,
"This procedure [that explains how to read NBU tapes with tar] will not work
with multiplexed tapes."

It also says that backups that span tapes have to be concatenated to be read
with tar.  IOW, you have to use dd to contatenate them to a disk, then use
tar to read the tar images from tape.

You also cannot read images that have been compressed using NBU compression,
or encrypted using NBU encryption.

My experience has also shown that you cannot easily read tapes that have a
fragment size other than 0 (infinite).

Feel free to try and prove me wrong on this one.  There are thousands of NBU
users that would love to know how to read their MPXd tapes with NBU tar.

> According to Netbackup Business Server 4.5 System
> administration Guide for UNIX p. 715 -Multiplexed backups
> cannot be read by any version of tar -gnu tar can't read
> compressed tape while netbackup tar
> (/usr/openv/netbackup/bin/) can. Netbackup tar is modified
> version of gnu tar.