Silicon Graphics POWER CHALLENGE User Manual page 60

Chapter 4: Installing Optional Peripherals
44
Each internally installed FLD must mount on a sled that uses a SCSI channel
adapter board. To determine the sled board settings, do the following:
• Be sure the sled-to-drive connector cable is plugged into the correct
SCSI channel: single-ended(A) or differential (B).
• Set both jumper blocks H1 and H2 on the sled board to reflect the SCSI
channel operation, regardless of which channel is plugged into the
drive (see Figure 4-2).
• If the SCSI backplane bus is only single-ended or only differential, set
all the jumpers in H1 and H2 for that mode of operation (see
Figure 4-2).
Incorrect jumpering on an unused jumper block can cause unwanted
Note:
noise on the bus.
The factory shipped your Challenge deskside server with Channel A
configured as single-ended and B as differential. If the system has been
modified, or if you are uncertain as to the configuration of SCSI Channels A
and B, you will have to remove an existing drive. Pull the locking lever on
the drive sled to the left and pull the drive and sled assembly gently out of
the rack. Compare the settings on the adapter board to those in Figure 4-1 or
Figure 4-2. Match the configuration of the new device's adapter board with
the intended mode of operation (single-ended or differential).
Your system disk should always be set to SCSI ID 1. Be sure each SCSI
Note:
device on a bus has a unique SCSI address (ID). The SCSI bus cannot
function properly if more than one device has the same SCSI ID.