NonStop NS-Series Operations Guide (H06.12+)

14 Power Failures: Preparation and Recovery
• “When to Use This Section” (page 151)
• “System Response to Power Failures ” (page 151)
— “NonStop NS-Series Cabinets (Modular Cabinets) ” (page 151)
— “External Devices ” (page 152)
— “ESS Cabinets” (page 152)
— “Air Conditioning” (page 152)
• “Preparing for Power Failure” (page 152)
— “Set Ride-Through Time” (page 152)
— “Monitor Power Supplies” (page 153)
— “Monitor Batteries” (page 153)
— “Maintain Batteries” (page 153)
• “Power Failure Recovery” (page 153)
— “Procedure to Recover From a Power Failure” (page 153)
— “Setting System Time” (page 153)
• “Recovery Operations for a File-System Error” (page 95)
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.
System Response to Power Failures
NonStop NS-Series Cabinets (Modular Cabinets)
NonStop NS-series servers are designed to operate in a computer-room environment containing
a site UPS. Without a UPS, a system will stop uncontrollably when the power is lost. An optional
UPS module can be installed in a modular cabinet to provide power if no site UPS is available.
If AC power to a NonStop NS-series server is lost, the system will shut down after a preset time
as long as UPS power is available. If the system shuts down, it will be necessary to restart the
system manually when AC power is restored.
If modular cabinets lose power without a UPS, recovery of lost data will be difficult and files
might be corrupted.
Regardless of system power-fail scenario, if site air conditioning fails and the computer-room
temperature rises, the system might shut itself down uncontrollably as each processor reaches
its critical temperature. Refer to the NonStop NS-Series Site Preparation Guide.
NonStop S-Series I/O Enclosures
NonStop S-series I/O enclosures have internal batteries and do not require a UPS. NonStop
S-series enclosures must shut down before their battery power is lost. For information about
power fail for I/O enclosures, refer to the NonStop NS-Series Planning Guide.
When to Use This Section 151