NonStop S-Series Operations Guide (G06.24+)

HP NonStop S-Series Operations Guide—522459-007
15-1
15
Power Failures: Preparation and
Recovery
When to Use This Section 15-1
How an Enclosure Responds to Power Failures 15-1
How External Devices Respond to Power Failures 15-2
With an Uninterruptible Power Supply (UPS) 15-2
Without an Uninterruptible Power Supply (UPS) 15-2
Preparing for Power Failure 15-3
Monitoring Power Supplies 15-3
Maintaining Batteries 15-3
Recharging Spare Batteries 15-3
Monitoring Batteries 15-3
Causes of Drained Batteries 15-3
Recharging Drained Batteries 15-4
Power Failure Recovery Operations 15-4
Procedure to Recover From a Power Failure 15-4
Setting System Time 15-5
Related Reading 15-5
When to Use This Section
Use this section for information about how to prepare for power failures and how to
recover if a power failure occurs.
How an Enclosure Responds to Power
Failures
Processor enclosures and I/O enclosures include a battery backup, whereas IOAM
enclosures do not. IOAM enclosures depend on the presence of an uninterruptible
power supply to accommodate power failures.
In the case of processor enclosures and I/O enclosures, the batteries in the enclosure
continue to operate all the components in the enclosure for a short, configurable period
of time, called the power-fail delay time. If the power failure lasts longer than the
power-fail delay time, the batteries maintain power to just the memory for as long as
they can, usually 45 minutes. The exact amount of time the batteries can maintain
memory depends on:
•
The power-fail delay time