HP StorageWorks SAN Virtualization Services Platform Manager user guide (5697-0295, January 2010)

2. Select Run Diagnostics. VSM sends a Read Sector command to sector 0 (zero) on the back-end
LU and retrieves the back-end LU’s response. The Back-End LU Diagnostic dialog box opens,
displaying the back-end LU’s response in the Read Sector tab.
Figure 9 Back-end LU diagnostics—Read Sector tab
.
3. Click one of the following buttons to send a SCSI command to the back-end LU. Results are
displayed on the screen.
• Get Inquiry—Returns some general details about the back-end LU, such as vendor, firmware
revision, and product ID.
• Test Ready—Checks whether the back-end LU is connected to the SAN and is functioning
properly and ready for use, and returns the status. Status 0 means that the back-end LU is
ready. If the back-end LU is not ready, the Sense Key, Sense Code, and Sense Qual fields
indicate the reason.
• Read Capacity—Status 0 indicates that the command was successful. The capacity field returns
the number of sectors on the back-end LU (in hexadecimal format).
• Start—Issues a start command to the back-end LU. Status 0 indicates that the command suc-
ceeded and the back-end LU is started.
• Activate—Attempts to reactivate a back-end LU whose status is Failed. If the operation is
successful, the screen displays “Back-End LU Activated” and the back-end LU status changes
to Present. If the operation is not successful, the back-end LU status remains Failed.
• Get Reserved State—Returns the state of any reservations on the selected LUN (SCSI-2 reserve
or SCSI-3 persistent reserve).
4. Click Cancel. The Back-End LU Diagnostic dialog box closes.
Working with back-end LUs62