Recovering From An Unplanned Power Outage; Manual Restart After Power Is Restored; To Restart The Disk Array Manually - HP StorageWorks XP20000/XP24000 - Disk Array Owner's Manual

2. Pull the switch up and then out towards you.
The disk array shuts down immediately. The UNIT EMERGENCY POWER OFF switch mechanically
locks itself in the off position to prevent anyone from restoring power in a potentially hazardous
situation.
WARNING!
The UNIT EMERGENCY POWER OFF switch provides only partial power off capability. AC input
power remains present at the primary circuit.
3. When the emergency situation is over, call the HP technical support center. Only a qualified HP
support representative can reset the switch and restore power to the disk array.

Recovering from an unplanned power outage

Unplanned power outages occur when the primary building power is lost due to electrical blackouts,
thunderstorm activity, or similar occurrences, and input AC power is not received by the disk array.
The disk array will maintain its state and recover when power is restored.
The disk array cache is powered by backup batteries that will maintain the array state for up to 48
hours, depending on the selected battery operation mode. For more information, see
"Backup batteries" on page 27.

Manual restart after power is restored

CAUTION:
After power is restored to your site and before restoring power to the disk array, HP recommends
that you have an electrician verify the power to ensure that all phases are restored and input power
to the disk is stable.
Contact your HP representative for help recovering from a power outage.

To restart the disk array manually

1. Move the PS ENABLE switch to the ENABLE position.
42 Operating the HP XP24000/XP20000 Disk Array