1. Administrator's Guide
  2. Logical Library Support
  3. Troubleshooting

Troubleshooting

This section describes some possible problem scenarios, and offers ideas on how to diagnose and resolve the problems.

What if a client cannot see the logical library that I've assigned?

  1. Make sure that ACSLS is running, by running acsss status.

    This utility shows if ACSLS is in general enabled.

    For FC problems, look at the smce service. This service provides the SCSI Media Changer interface to logical libraries.

  2. If ACSLS is running, check to make sure your client connections have been defined correctly.

    • You may have assigned a target-initiator pair that is not really connected over FC

    • You may have assigned the logical library to the wrong client (the wrong target-initiator pair)

    • The getHba.sh utility can be useful in identifying which initiators (clients) are detected and which ones are connected to specific target ports.

What if a client is connected correctly, but still doesn't see the logical library?

You may need to force the client to re-discover target devices. The actual mechanism depends on the operating system of the client system. The client OS must be able to see the device before any client application is able to use it.

For example, on a Solaris client, the cfgadm and devfsadm commands can be used to update the device file system and configuration.

What if a client has trouble configuring to a logical library?

A client backup application may not recognize the ACSLS logical libraries as a supported library type. Logical libraries return a unique inquiry string which may require an update from the software vendor. An application-specific mapping file may also be required in order to configure the library and its tape drives correctly.

Sometimes, client software expects that a tape library always appears as LUN 0 on a SCSI target. Normally, the first logical library on a target port for a client would, in fact, be presented as LUN 0. However, if multiple libraries are assigned to a client on a given target port, they cannot count on always seeing a library as LUN 0. This is a client issue.

How to Configure an FC Port in Target Mode

During installation, you are asked to select an HBA to be used as a target port. This operation applies only if you intend to present one or more logical libraries to SCSI (FC) client applications.

After installation, use the getHba.sh utility to configure a Fibre Channel port in target mode. The getHBA.sh utility can be run any time a new HBA has been added to the system, or any time the HBA ports are re-arranged. This utility identifies an appropriate HBA port to change from initiator to target mode in order to reveal a client access point to ACSLS logical libraries.

If you intend to configure one or more logical libraries for SCSI direct, attach clients, then select the HBA that should be converted from initiator mode to target mode. Ideally, the HBA that you select is connected to the fabric, and has visibility to the remote HBA intended as the SCSI client initiator.

Once the target-mode change has been set for the given HBA, a reboot is necessary in order to complete the HBA conversion.

To configure a Fibre Channel port in target mode, complete the following procedure:

  1. Login as root
  2. Go to the $ACS_HOME/install directory, or include it in your path.
  3. Run getHba.sh

Example:

# ./getHba.sh
Please select the HBE port you intend for Target-mode operation:
Select from the following list:
1)HBA Port WWN 210000lb3213ble2   Not connected.
2)HBA Port WWN 210100lb3233ble2   Not connected.
3)None of these.
2
HBA Port WWN 210100lb3233ble2/pci@1,0/pci1023,7450@1/pci1077,141@3,1
Is this correct? (y or n):y
Are there additional ports you wish to reconfigure? (y or n):n
A reboot will be necessary for these changes to take effect.