Scsi Sense Data Definition; Scsi Sense Data - Library Error - IBM TS3100 Setup, Operator, And Service Manual

v For library errors [Resource Name = smcn (for example, smc0) and Resource
v For drive errors [Resource Name = rmtn (for example, rmt0) and Resource Type
v For fibre channel errors (not fibre channel adapter errors), determine which host
v For fibre channel adapter errors (not fibre channel bus errors), use the
Note: See Appendix D, "Sense Data," on page D-1 for further details on sense

SCSI Sense Data Definition

Following is an example of a tape drive communication failure while attached to
an Open Systems host through a fibre channel link, using SCSI protocol. When the
host detected the failure, it built the following SCSI Sense Data record. An
explanation of the SCSI Sense Data breakout in this example follows.
SENSE DATA
aabb xxxx ccdd eeee eeee eeee eeee eeee ffgg hhxx ssss ssss
0600 0000 1200 0000 0000 0000 0000 0000 0200 0300 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000
Note: The bold area above represents the SCSI Sense Data presented by the host. The regular font data (in this case
many bytes of 'zero'), designated by 'ssss' would normally contain device sense data, but with the kind of
failure in this example (COMMAND TIMEOUT), the host could not collect valid device sense data, so zeros
are the result and should be ignored. If the host had been able to collect valid sense data from the drive, the
first byte 'ss' would be '70', '71', 'F0' or 'F1', and valid device sense data would be listed.
DETAIL DATA
aabb xxxx ccdd eeee eeee eeee eeee eeee ffgg hhxx ssss ssss
aa Length of the Command Descriptor Block (CDB) sent by the host. In this case, '06' bytes.
bb SCSI target address. In this example, SCSI address '00'.
xx Unused or reserved
cc Start of CDB, cc is the operation code (byte 0). In this case, '12' which was an "Inquiry".

SCSI Sense Data - Library Error

The following example of SCSI Sense Data was received from an RS/6000 Open
System host and shows a Tape Drive Failure and what the sense data would look
like. Unlike the previous situation with "SCSI Sense Data Definition", this data
contains valid sense data as defined by the hex '70' in the first sense byte position.
Therefore, instead of all zeros as in the previous example, we have valid data to
rely on. While the data shows that this is a TAPE_ERR2, it could also be caused by
a library failure. As described above, the resource name is smc0 indicating a library
error. The ASC/ASCQ points to a "Mechanical Positioning Error" while attempting
a "Move Medium" command ('A5'). For more information about Sense Data,
E-2
TS3100 Tape Library and TS3200 Tape Library Setup, Operator, and Service Guide
Type = 3573-TL]), refer to "SCSI Sense Data Definition" and Sense Data in
Appendix C.
= LTO], refer to "SCSI Sense Data Definition" and Sense Data in Appendix C.
adapter and device are affected, and go to that host documentation to resolve
any fibre channel problems. If unsuccessful, call for IBM support.
maintenance package for the host.
data.
ssss ssss ssss ....
ssss ssss ssss ....