Technical data

18
Chapter 2: Chassis Tour
Table 2-1 SGI 2400 and 2800 Major Components
Component Description
1. Module A/Module B The modules shown in Figure 2-1 are independent computing
subsystems with a separate set of CPUs (central processing
units) disks, System Controller, and I/O connections. There
can be up to two modules in a rack and up to sixteen modules
in a multirack configuration.
2. Optional SCA disk
modules
Each module can house up to five SCA (single connector
attachment) drives (including the system disk). The disks are
single-ended, ultra SCSI drives with a transfer rate of
40 MB/sec.
3. System disk The system disk contains the operating system and other key
software directories. The system disk must be installed in the
drive position shown in Figure 2-1. Note that the system disk
is oriented differently than the other drives in the system. See
“Loading the Single Connector Assembly (SCA) Drives Into
the System” on page 63 for additional information.
4. System
controller/drive
module door
This door should be kept closed to prevent dust and other
possible contaminants from affecting the drive performance.
5. CD-ROM drive The CD-ROM is standard with each system and is used to load
the operating system and software applications.
6. Module System
Controller
The module System Controller (MSC) is an independent,
microprocessor-controlled device that powers on and helps
boot the system. The MSC also contains a key switch for
turning on and turning off the module.
7. Multimodule System
Controller
display
The multimodule System Controller (MMSC) display is an
intelligent keypad interface that can control all the system
modules in a rack. The MMSC display (also known as the
full-feature System Controller—FFSC) has greater
functionality than the MSC display. There can only be one
display per rack configuration.
8. SCSI drive box This drive box enclosure provides six half-height 3.50-inch
drives and two full-height, 5.25-inch drive slots for
single-ended and SCSI drives.