Chapter 3 System Administration 65
The system reports and logs correctable ECC errors. A correctableECC error is any
single-bit error in a 64-bit field. Such errors arecorrected as soon as they are
detected. The ECC implementation can also detect double-bit, triple-bit, and
quadruple-bit errors in the same 64-bit field that occur in the same nibble (4 bits).
In addition to providing ECC protectionfor data, the system offers parity protection
on all system address buses. Parity protection is also used on the Peripheral
Component Interconnect (PCI), Extended PCI, Fibre Channel-Arbitrated Loop (FC-
AL), and Small Computer System Interconnect(SCSI)) buses, and in the UltraSPARC
CPU’s internal and external cache. In addition there is internal error detection and
reporting on all system application specific integrated circuits (ASICs).
Easily Accessible Status LEDs
The system provides easily accessible light-emitting diode (LED) indicators on the
front panel, internal disk bays, and power supplies to provide a visual indication of
system and component status. These status LEDs eliminate guesswork and simplify
problem diagnosis for enhanced serviceability.
The system status LEDs are described in the section “System LED Indicators” on
page10.
Hot-Pluggable Disk Drives
When configured with hot-plug software (for example, the Sun Solstice DiskSuite or
VERITASsoftware; see “About Storage Management Tools” on page 76), the
system’s internal disk drives can be removed and replaced while the system is
operational. Youcan easily access the internal drives from the front of the system.
The same hot-plug technology is also supported via PCI FC-AL, or UltraSCSI
adapter cards using external storage. Withboth internal and external technologies
installed, hot-plug technology significantly increases the system’s serviceability and
availability,by providing the ability to:
■Replace disk drives without service disruption
■Increase storage capacity dynamically to handle larger work loads and improve
system performance
For more information about hot-pluggable disk drives, see “About Internal Disk
Drives” on page 91 and “About Disk Array Configurations andConcepts” on
page87.