Reference Guide

Chapter 4 SCSI Commands
MODE SELECT (6) / (10) Command (15h / 55h)
DLT-S4 Interface Reference Guide 149
General Operation 4 The password(s) are written to the drive using a MODE SELECT command
for the Vendor-Unique Data Security Mode page. The password value
will not be returned in the
MODE SENSE data. The drive will create
password protected tapes as instructed by the Action Code of the
MODE
SELECT
command.
At the end of the load process there is a determination if the tape is
password protected. If the tape is password protected, the password(s) on
the tape will be compared to the password(s) in the drive. If the
password(s) are equal, subsequent write and read operations are allowed.
If the passwords do not match, the following operations will be rejected
and sense data presented to the host:
WRITE, WRITE FMs, READ, LOCATE,
VERIFY, ERASE, SPACE, WRITE ATTRIBUTES, SEND DIAG and WRITE
BUFFER. If the tape is not password protected and the action code is to
password protect the tape, then the passwords are written to tape at the
next possible opportunity (when the tape is positioned at BOT).
In the event of a password mismatch, the following commands are
rejected:
WRITE, WRITE FMs, READ, LOCATE, VERIFY, ERASE, SPACE, WRITE
ATTRIBUTES, SEND DIAG, and WRITE BUFFER.
The sense data returned when one of these commands is rejected is:
• Sense data (0x07, 0x20, 0x03) Data Protect, Access Denied, Invalid
Management ID Key.
In the event of an attempt to disable a password protected tape or add a
password to a non-protected tape when not at BOT, the following sense
data will be available on the interface:
• Sense data (0x05, 0x82, 0x00) Illegal request, Action not allowed away
from BOT.
PM Password Mismatch. This read only bit indicates that this password on the tape does not
match this password set in the drive.
Password This is a 32 byte write only field used to set the drive password to the desired value for the
requesting interface. The password value is secret and will not be reported in
MODE SENSE
data. Instead, the password reported by the MODE SENSE command is all zeroes. For
actions other than 00 or 05, the password must be non-zero or the command will be
rejected. The password is cleared using action code 05 – Clear Drive Password
Field Description