Hot-Swappable Power Supplies
Power supplies in a redundant configuration feature a "hot-swap" capability. You
can remove and replace a faulty power supply without shutting down the operating
system. The power supplies are easily accessed from the rear of the system, without
the need to remove system covers.
Redundant, Hot-Swappable Fan Trays
The basic system configuration includes two sets of three fan tray assemblies to
provide system cooling. One set of three fan tray assemblies provides primary
cooling, and the other set ensures redundancy that protects against cooling failures.
Only the primary fan trays are active during normal system operation. If a primary
fan tray fails, the environmental monitoring subsystem detects the failure and
automatically activates the appropriate secondary fan tray.
All fan trays feature a hot-swap capability. Qualified service technicians can remove
and replace a faulty fan tray without shutting down the operating system. For
additional details, see "About Fan Trays" on page 64.
Environmental Monitoring and Control
The Sun Fire V890 system features an environmental monitoring subsystem
designed to protect against:
Extreme temperatures
Lack of adequate airflow through the system
Power supply problems
Monitoring and control capabilities reside at the operating system level as well as in
the system's flash PROM firmware. This ensures that monitoring capabilities remain
operational even if the system has halted or is unable to boot.
The environmental monitoring subsystem uses an industry standard I
bus is a simple two-wire serial bus, used throughout the system to allow the
monitoring and control of temperature sensors, fans, power supplies, status LEDs,
and the front panel keyswitch.
2
C bus. The I
Chapter 1 System Overview
2
C
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