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Description
NetBackup appliances have two, modular power supplies for high availability operation. During normal operation, the power supplies are configured for active standby operation. In this configuration, one power supply is used to provide power for the entire system and the other is held in reserve. Should the active power supply fail, the system automatically shifts the load to the power supply that is held in reserve.
The power supplies are designed to enter protection mode when an electrical event that is potentially catastrophic occurs. Such events include short-circuits, voltage overloads, and power surges. In protection mode, the power supply shuts down or locks up to protect itself and the component in the system.
When the unit is running, it may be turned off incorrectly or inadvertently. The control panel in front of the unit may show a fault. The LEDs on the power supplies in the rear of the unit may show a fault.
Possible causes include the following:
AC power input to the power supplies is incorrect.
The power supply is faulty or in protection mode.
The CPU is in over-temperature protection mode.
Caution: |
To ensure power to the system in not interrupted, periodically check the reserve power supply. Make sure that the unit is turned on and operating properly. |
Power supply modules are easily accessed from the rear of the unit. They are installed side-by-side on the left-hand side of the unit. Each contains an AC socket, switch, LED, and fan. The LED on the power supply provides information about the power supply status.
Note: |
The power supplies are designed to enter protection mode when an electrical event that is potentially catastrophic occurs. Such events include short-circuits, voltage overloads, and power surges. In protection mode, the power supply shuts down or locks up to protect itself and the component in the system. |
You can remotely gain information about the current status of an appliance power supply using one of the following user interfaces:
In the NetBackup Appliance Web Console use Monitor > Hardware page to view the power supply information.
In the NetBackup Appliance Shell Menu use Main_Menu > Monitor > Hardware .
You can also gather information about the power supply by viewing the LEDs on the front and the rear panels of the unit. If the power button and LED on the front control panel is amber, one or both power supplies may be faulty. Check the LEDs on the power supplies on the back of the unit to determine which power supply is faulty. You can use the following procedure to verify that the power supply is faulty.
To determine if the AC input to the power supplies is correct
Check to see if the power button/LED on the control panel and the LED near each AC power socket are off.
If an LED is off, remove and reinsert the AC power cable to the power supply at the power source. Do the following:
If the power button LED flashes green, the abnormal lock-up is due to a loose plug connection. Operations should continue normally.
If the LEDs are still off, it is possible that AC power to the equipment room is faulty. In this case, contact the customer for resolution.
If the equipment room power is normal, replace the power supply.
If the power button is amber, check other components such as fans and CPUs for further analysis.
To determine if a power supply is faulty or in protection mode
For each power supply, check the power button LED and the power supply LED.
If both the LEDs are amber, replace the power supply.
If only one LED is amber, check other components such as fans and CPUs for further analyses.
To determine if the CPUs are in over-temperature mode
Access the NetBackup web Appliance console and click Monitor > Hardware .
Check the alarm list.
Review the list for temperature- and fan- related alerts such as the following:
Alert information
Description
Overtemperature
Temperature is not critical yet but approaches the upper limit of the range.
Absence
A component such as a fan is absent.
If an alarm about the CPU overtemperature appears, several problems may be the cause including the following:
Improper installation or damage of the air duct inside the chassis.
Fan and or air intake or output problems.
Excessive equipment room temperature (room temperature should be between 10° C and 35° C (50° F - 95° F).
Inspect the fans in the power supplies on the rear left-hand side of the unit. Verify that there are no obstructions or damage.
Inspect the air intake and output vents in the front panel and rear panel of the unit. Verify that there are no obstructions or damage.
If the room temperature is too high, reduce the temperature at a rate of no more than 10° C per hour until an acceptable temperature is reached.
Access the NetBackup Appliance Web Console and verify that the CPU temperature has decreased.
If CPU temperature does not return to normal, escalate as necessary. The unit may require replacement.
To determine if one, or both, power supplies are faulty
On the rear panel, locate the power supply that has the amber LED.
Make sure that the other power supply functions properly.
Unplug the power cord from the power supply that has the amber LED.
Wait for 2 minutes or for 3 minutes, then plug in the power cord.
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Caution:
The unit functions normally with one power supply. However, data and operation is at risk if the second power supply fails. The faulty power supply should be replaced as soon as possible.
Warning:
To ensure that the unit does not overheat, do not operate the unit with the power supply bay empty for more than a few minutes. Leave the failed power supply in the bay until the replacement power supply is available.
If both power supplies have amber LEDs, shut down the unit and obtain replacements.
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Translated Content
Please note that this document is a translation from English, and may have been machine-translated. It is possible that updates have been made to the original version after this document was translated and published. Veritas does not guarantee the accuracy regarding the completeness of the translation. You may also refer to the English Version of this knowledge base article for up-to-date information.