System Functions; Hot Swapping; Hot Plug Pci; Fans - NEC Express5800 series User Manual

System Functions

The following subsections describe select system functions.

Hot Swapping

Hot swapping allows a device to be replaced, such as a hard disk drive while its power
is on, as listed below.
!
Disk array system:
Any failed hard disk drive can be replaced while the system is running.
!
Hot swap fans:
Any one of the four system fan modules (one or two fans per module) can be
replaced while the system power is on.
!
Redundant Power system:
When three power supplies are installed on the four processor system a failed power
supply can be replaced by hot swapping.

Hot Plug PCI

Four Hot Plug PCI bus slots are located behind the Hot Plug PCI door of the server.
These PCI slots allow PCI-X boards to be installed or removed while the server is
powered on (if the operating system supports the Hot Plug PCI function.)
Note: Windows NT 4.0 does not support the Hot Plug PCI
function.

Fans

All access covers must be on the system for proper cooling. To
ensure that all components remain within specification under all
system environmental conditions, do not exceed five minutes for hot
swapping of fans or power supplies.
The server comes with four fan modules. Air enters through the bezel, passes through
the fan bay and electronics bay, and exhausts through the rear of the chassis. The power
supply modules and hot-swap hard drive bays also come with their own fans which
draw air through those components and through the peripheral bays.
Under normal system conditions, the fans run at a slower, quieter speed. If a fan failure
is sensed, a fan is not detected, or ambient temperature exceeds a certain limit, the fan
speed is set to high. Also, any one of the four system fan modules (one or two fans per
module) can be replaced while the system power is on.
LEDs indicate if individual fans are inoperative or not present. Under the same fan
failure conditions, the general system fault LED on the front panel is lit.
1-22 System Overview
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