System And Scsi Backplanes; Scsi I/O Devices; System Controller - Silicon Graphics POWER CHALLENGE User Manual

Chapter 1: Introducing the Challenge Deskside Servers

System and SCSI Backplanes

SCSI I/O Devices

System Controller

8
The enclosure comes with an 11-slot cardcage and backplane that includes
five VME expansion slots. Note that only two VME slots are available when
a POWER Challenge system uses the optional visualization console.
To the right of the cardcage is room for seven half-height (or one half-height
and three full-height) SCSI devices. Each drive sits in its own individual
"sled" and slides into the drive rack. When fully inserted, the drive and sled
assembly plugs into the SCSI backplane at the rear of the rack.
See the "SCSI Drive Rack" section of Chapter 2 for specific information about
peripheral locations.
SCSI drives are the only devices internally supported by the Challenge
deskside system. The system's drive rack has space for seven half-height
devices. All drives must be front loaded after being mounted on a special
drive sled. Supported devices include hard disks, Digital Linear Tape (DLT)
drives, 1/4-inch cartridge, 4-mm and 8-mm tape drives, and CD-ROM
drives. Installing a full-height drive (such as the 8-mm or DLT) requires
using two half-height slots. See Chapter 4 for installation instructions.
Located just above the SCSI drive rack is an on/off key switch and the
System Controller display panel. The System Controller is a
microprocessor-controlled, subsystem that is mounted directly to the system
backplane. It monitors various system operations, including chassis
temperature, system fan speed, backplane voltages, and the system clock.
Battery backup supports the System Controller's NVRAM and time-of-day
system clock.
When any operating parameter exceeds or drops past a specified limit, the
System Controller can execute a controlled shutdown of the Challenge
deskside system. During such a shutdown procedure, the System Controller