• Warning. A problem occurred that may affect system stability, but not data integrity. Evaluate the
problem and correct it if necessary.
• Informational. A configuration or state change occurred, or a problem occurred that the system
corrected. No immediate action is required.
The event logs record all system events. It is very important to review the logs, not only to identify the fault,
but also to search for events that might have caused the fault to occur. For example, a host could lose
connectivity to a disk group if a user changes channel settings without taking the storage resources
assigned to it into consideration. In addition, the type of fault can help you isolate the problem to either
hardware or software.
Isolate the fault
Occasionally, it might become necessary to isolate a fault. This is particularly true with data paths, due to
the number of components comprising the data path. For example, if a host-side data error occurs, it could
be caused by any of the components in the data path: controller module, cable, switch, or data host.
If the enclosure does not initialize
It may take up to two minutes for all enclosures to initialize. If an enclosure does not initialize:
• Perform a rescan
• Power cycle the system
• Make sure the power cord is properly connected, and check the power source to which it is connected
• Check the event log for errors
Correcting enclosure IDs
When installing a system with drive enclosures attached, the enclosure IDs might not agree with the
physical cabling order. This is because the controller might have been previously attached to enclosures in
a different configuration, and it attempts to preserve the previous enclosure IDs, if possible. To correct this
condition, make sure that both controllers are up, and perform a rescan using the SMC or the CLI. This will
reorder the enclosures, but can take up to two minutes for the enclosure IDs to be corrected.
To perform a rescan using the CLI, type the following command:
To rescan using the SMC:
1. Verify that both controllers are operating normally.
2. Do one of the following:
• Point to the System tab and select Rescan Disk Channels.
• In the System topic, select Action > Rescan Disk Channels.
3. Click Rescan.
NOTE: The reordering enclosure IDs action only applies to Dual Controller mode. If only one controller is
available, due to either Single Controller configuration or controller failure, a manual rescan will not
reorder the drive enclosure IDs.
When troubleshooting disk drive and connectivity faults, stop I/O to the affected disk groups from all hosts
as a data protection precaution. As an additional data protection precaution, it is helpful to conduct
regularly scheduled backups of your data.
IMPORTANT: Stopping I/O to a disk group is a host-side task, and falls outside the scope of this