How to read a tape header to verify the recorded volume serial number

1. Use the tpreq command to load a tape. The format is:
/usr/openv/volmgr/bin/tpreq -ev <external volume serial number> -d <density> -p <poolname> -f <filename>

Example: /usr/openv/volmgr/bin/tpreq -ev CHM292 -d dlt -p NetBackup -f /tmp/292

The tape is loaded into an available drive, and a link is created from /tmp/292 to the device such as /dev/rmt/0cbn. The link is used to "talk" to the drive/tape.

2. Issue the following command to rewind the tape:
mt -f <file name> rewind

Example: mt -f /tmp/292 rewind

3. Issue the following command to read the header:
dd if=<file name> bs=1024 | od -cx

Example: dd if=/tmp/292 bs=1024 | od -cx

The output of this command will look like this:
0000000   V   O   L   1   C   M   H   2   9   2  \0  \0  \0  \0  \0  \0       <--------------This is the recorded volume serial number.
           564f    4c31    434d    4832    3932    0000    0000    0000
0000020  \0  \0  \0  \0  \0  \0  \0 001  \0  \0  \0  \r   9 346   4 324
           0000    0000    0000    0001    0000    000d    39e6    34d4
0000040  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0
           0000    0000    0000    0000    0000    0000    0000    0000
0000060  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0 001  \0  \0  \0 001
           0000    0000    0000    0000    0000    0001    0000    0001
0000100  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0 004  \0  \0  \0  \0  \0
           0000    0000    0000    0000    0000    0400    0000    0000
0000120  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0
           0000    0000    0000    0000    0000    0000    0000    0000
*
0000160   T   h   I   s       I   s       A       B   P       t   A   p
           5468    4973    2049    7320    4120    4250    2074    4170
0000200   E       h   E   a   D   e   r  \0  \0  \0  \0  \0  \0  \0  \0
           4520    6845    6144    6572    0000    0000    0000    0000
0000220  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0
           0000    0000    0000    0000    0000    0000    0000    0000
*
1+0 records in
1+0 records out
0002000

Note:  If in doubt as to which block size to use in the above command, verify the header block size by running the " tcopy " command. On the Solaris platform the command format is: tcopy <file name>

Example: tcopy /tmp/292

The output looks like this:
file 1: record 1: size 1024
file 1: eof after 1 records: 1024 bytes.

Cntl' C (^C) out of the command after verifying file1, then rewind the tape again.

4. Issue the following command to rewind the tape:
mt -f <file name> rewind

Example: mt -f /tmp/292 rewind

5.Use " tpunmount " command to unmount the tape.  The format is:

/usr/openv/volmgr/bin/tpunmount -f <file name>

Example: /usr/openv/volmgr/bin/tpunmount -f /tmp/292