138 CHAPTER 8: MANAGING UNINTERRUPTIBLE POWER SUPPLIES
VCX Server Response to Power Events

This section describes how UPS-supported VCX systems respond to

various power events.

Power events and VCX server responses are shown in Tabl e 11.

Table11 VCX Server Behavior for Power Events

Event Response
Power Loss When one or more VCX servers are connected to a UPS and
a power loss occurs, the servers continue to operate without
interruption. The servers do not initiate a shutdown unless
the UPS battery power level is below the threshold capacity
for shutdown (for example, because the UPS battery has not
yet fully recharged after a prior power loss event).
A power loss event is detected by VCX software, logged
through syslog, and reported as an SNMP trap.
Power Restoration
Prior to Depleted
Battery
If power returns while a VCX server is operating on UPS
battery power, the VCX server:
■Logs the event through syslog.
■Generates an SNMP trap indicating return of power.
■Resumes normal operation.
Depleted Battery Each UPS is configured with a battery threshold. The
threshold charge is expressed as a percentage of remaining
battery power. The default is 25%. When the UPS battery
reaches the configured threshold, a VCX server:
■Logs this event through syslog.
■Generates an SNMP trap indicating that shutdown is
imminent.
■Starts an orderly shutdown of services and the VCX
operating system.
If the VCX system has multiple UPS devices providing power,
the depleted battery event occurs only when both UPS
devices are running on battery and are at or below the
low-battery threshold.