Tape library problems

Description

A tape library reports the same barcode in different locations.

Explanation

It could happen that the tape library reports the same medium barcode in a drive and in a slot at the same time. In this case OpenArchive (OA) writes an error message to the OA error log file, and marks both the medium and the drive as unusable. This happens when you manually move the medium from the drive to the slot, and then start the library inventory rescan.

Workaround

To resolve this situation, perform either of the following steps:
• Manually move the medium back to the same drive and clear the slot.
• Clear the drive and trigger inventory for the slot to which the cartridge was moved.
Full inventory rescan is not recommended in such cases, since it may take considerable amount of time.

Description

On the consolidated OA system or OA server with an HP StorageWorks MSL library connected, after you query for detected SCSI devices, only the medium changer of the library appears in the list.

(Red Hat Enterprise Linux system specific)

Explanation

The Red Hat Enterprise Linux kernel only detects devices with a LUN of zero. HP StorageWorks MSL libraries use different LUNs for each library unit (medium changer, tape drive, and embedded router). As a result, only the medium changer is detected and the library cannot be used.

Workaround

Proceed as follows:
1. Add the following line into the file /etc/modules.conf:
options scsi_mod max_scsi_luns=255
2. Using the mkinitrd command, rebuild the initial RAM disk.
3. Restart the system.
4. Invoke the following command:
# echo "scsi scan-new-devices" > /proc/scsi/scsi
5. Inspect the output of the following command to determine if all missing devices have been detected: # cat /proc/scsi/scsi

If the missing devices are listed, add the command you ran in step 4 to your Linux system startup script, in order to ensure that all devices are accessible after the Linux system is started. You can now start using the OA implementation. If the missing devices are not listed, proceed with the next steps.

6. For each missing device, invoke the following command. In place of parameters H, B, T, and L, specify the HBA number, SCSI bus number, target SCSI ID, and LUN of the device, respectively: # echo "scsi add-single-device H B T L" > /proc/scsi/scsi
7. Run the command from step 5 to verify that the missing devices have been detected.
8. Add each command that you ran in step 6 to your Linux system startup script.

Description

A bad drive cannot be removed if a medium is still in it.

Explanation

When trying to remove a drive from the OA implementation, the command ivddrive --remove Name reports a problem when trying to unload the medium, and the drive cannot be removed from the system.

Workaround

If the medium could not be unloaded, you must identify the reason and unload the medium manually. Then place the medium into a free slot in the OA library and enter the command
ivdlibrary --update-inventory LibraryName --rescan to trigger an inventory update and rescan the inventory. When complete, remove the drive using the command ivddrive --remove Name
again.

Description

After reconfiguring an OA drive, the OA implementation loads or unloads a different OA drive instead of the newly reconfigured drive.

Explanation

During reconfiguration, the Library Agent is not notified about the new drive device file or ID, and still uses the old device file or ID.

Library Agent uses drive device files for addressing OA drives.

Workaround

After an OA drive is reconfigured with a modified ControlDevice variable, restart the OA implementation using the ivd --restart command.