HP StorageWorks MSA 2.8 SAN Switch - Manual (Page 211)

Troubleshooting
211 Fabric OS Procedures Version 3.1.x/4.1.x User Guide
Check the power supply status. Refer to the HP StorageWorks Fabric OS
Version 3.1.x/4.1.x Reference Guide or refer to the switch installation guide
supplied with your specific switch (the installation guide is also available on
the v3.1.x or v4.1.x Software CD) for details regarding the power supply
status.
If any of the power supplies show a status other than OK, consider replacing
the power supply as soon as possible.
Check the Temperature, Fan, and Power Supply
1. Log into the switch as User.
2. Enter sensorshow at the command line. Refer to the HP StorageWorks
Fabric OS Version 3.1.x/4.1.x Reference Guide for details regarding the sensor
numbers.
3. Check the temperature output.
Look for indications of high or low temperatures.
4. Check the Fan speed output.
If any of the fan speeds display abnormal RPMs, replace the fan FRU.
5. Check the Power Supply status.
If any of the power supplies show a status other than OK, consider replacing
the power supply as soon as possible.