System Cabling Configurations C-7
BSU and DEU RAID Cable Configuration
The RAID options available for your system provide your system with the
added security of fault tolerance.
If you order a system with a RAID controller, the system is pre-cabled at the
factory (see Figure C-3 "BSU and DEU RAID SCSI Bus Cable Configuration".)
If you are adding a RAID controller you must install, cable, and configure the
controller. Refer to "Installing a RAID Controller Board" in Chapter 4.
One of the standard features of your BSU and DEU tower-based system is the
three channel SecuRAID 530 (Mylex eXtremeRAID 1100) controller board,
which gives your system the added security of fault tolerance. Your tower-based
system has RAID pre-cabled at the factory. The RAID controller is installed in
PCI slot #21 and the third channel (2) is used to control the hot-swap hard disk
drives in the DEU.
The on-board Ultra 160/m and Ultra2 wide SCSI controller AIC 7899 contains
two independent SCSI channels that share a single PCI bus master interface.
Each channel is capable of operations using either 8- or 16-bit SCSI providing
160 MB/s (Ultra 160/m) or 80 MB/s (Ultra2-Wide) throughput. SCSI controller
A is used to support SCSI devices in the two 5 1/4-inch removable media bays.
A 68 pin to 50 pin converter is also available to be used when installing SCSI
narrow devices. SCSI controller B is not used when the RAID controller is
installed.
Figure C-3 illustrates the BSU internal SCSI bus cable configuration when a
RAID controller is present and connected to a DEU. The RAID controller (D)
has external cable connectors (P) that interface to DEUs (I).
The cable routing for the different BSU and DEU SCSI channel configurations
are listed in the following figures:
! Figure C-4 — shows the external cable routing for a single channel BSU
disk array interfacing with one DEU (without the two channel option.)
! Figure C-5 — shows the external cable routing for two channel BSU disk
array interfacing with one DEU (with the two channel option.)
! Figure C-6 — shows the external cable routing for two channel BSU disk
array interfacing with two DEUs (without the two channel option.)
A 3 1/2-inch diskette drive is installed in the system and interfaces separately to
the system I/O board.
The on-board SCSI controller A also includes a connector located at the rear of
the system for connecting external Ultra2-wide devices.