HP NonStop NS Preparing for Power Failure, ESS Cabinets, Air Conditioning, Set Ride-Through Time

Power Failures: Preparation and Recovery ESS Cabinets

During a power failure, a ServerNet/DA remains operational during the power-fail delay time, but the external modular disk and tape subsystems attached to it do not. This type of situation could result in data-integrity problems if the system software continues processing data from an external disk drive or tape drive during a short power outage.

If a power failure occurs and the processors resume operations but one or more external devices fail, data integrity problems can occur. The application programs must be resilient to such device failures.

ESS Cabinets

ESS cabinets require a site UPS. ESS cabinets are not powered off programatically with a power failure because they may be attached to other systems.

Air Conditioning

Unless the site UPS provides for maintaining air conditioning, it is possible that the temperature could rise in the computer room complicating the ability of a system to survive overheating before shutting itself down. For information about site overheating problems, refer to the NonStop NS Series Site Preparation Guide.

Preparing for Power Failure

To prepare for power failures, set ride-through time, configure OSM power fail support, and regularly monitor power supplies and batteries.

Set Ride-Through Time

Ensure that the system is set for the proper ride-through time. The default powerfail delay time for NS-series systems that are configured with rack-mounted UPSs is 30 seconds. Contact HP Expert Services for the optimum ride-through time for your system.

The ride-through time is set using the SCF commands to alter the

POWERFAIL_DELAY_TIME parameter. Refer to the SCF Reference Manual for the Kernel Subsystem.

Configure OSM Power Fail Support

You must also configure OSM power fail support by performing a Configure Power Source as UPS action for at least one processor switch power supply unit (for Integrity NonStop NS16000 systems) or one IOAM or VIO power supply unit (for Integrity NonStop NS14000 or NS1000 systems). Configuring at least one power supply as being powered by UPS in the event of a power outage causes OSM to monitor a power outage and, if the AC power is not restored before the specified ride-through time period expires, OSM initiates an orderly system shutdown.

For more information, see the NonStop NSxxxx Hardware Installation Manual for your Integrity NonStop NS16000, NS14000, or NS1000 server or the OSM Service Connection User’s Guide.

HP Integrity NonStop NS-Series Operations Guide—529869-005

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