SAN problem determination

The procedures to service the SAN Volume Controller that are provided here help you solve problems on the SAN Volume Controller and its connection to the storage area network (SAN).

SAN failures might cause the SAN Volume Controller cluster to be unable to form or they might cause SAN Volume Controller disks to be inaccessible to host systems. Failures can be caused by SAN configuration changes or by hardware failures in SAN components.

The following list identifies some of the hardware that might cause failures:

Power, fan, or cooling switch
Application-specific integrated circuits
Installed small form-factor pluggable (SFP) connector
Fiber-optic cables

Perform the following steps if you were sent here from either the Maintenance Analysis Procedures or the error codes:

If the customer has changed the SAN configuration by changing the fibre-channel cable connections or switch zoning, ask the customer to verify that the changes were correct and, if necessary, reverse those changes.
Verify that the power is turned on to all switches and redundant array of independent disk (RAID) controllers that the SAN Volume Controller uses and that they are not reporting any hardware failures. If problems are found, resolve those problems before proceeding further.
Verify that the fibre-channel cables that connect the SAN Volume Controllers to the switches are securely connected.
If the customer is running a SAN management tool that you are familiar with and that you have access to, you can use that tool to view the SAN topology and isolate the failing component. You can also review Viewing the fibre-channel fabric connections to understand the SAN Volume Controller view of the SAN.