IBM PC Server 520, Руководство пользователя

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Connecting External Options
Adding External SCSI Devices
Notes:
1. If you plan to install both internal and external SCSI
devices, you must follow the instructions given in “SCSI
Drives” on page 218 in addition to the instructions in this
section. Read “SCSI Drives,” and then return here.
2. You cannot use both 16-bit SCSI-2 connectors on the
system board to support internal SCSI devices, and also
use the external connector at the same time.
If you plan to install external SCSI devices, you must order an
additional SCSI cable. That is, to use external devices with the PC
Server 520, you must connect them to the external SCSI-2 connector,
using a SCSI cable. This SCSI cable must have the proper connector
for the SCSI-2 external connector on one end, and the proper
connector for the first external device on the other end. To select
and order the correct SCSI cables for use with external devices,
contact your IBM reseller or IBM marketing representative.
The SCSI-2 adapter for disk-array models has three channels;, each
channel supports up to 15 devices. If you are not using all three
channels for internal devices, the adapter can support up to 15
external devices by using the external SCSI-2 connector on
Channel 1. When you connect external devices to this connector,
you can use only Channel 2 and Channel 3 on the adapter for
internal devices.
The SCSI-2 connectors on the system board can support a total of 15
devices. If your server has seven internal devices, the SCSI-2
external connector can support up to seven external devices.
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PC Server 520 User's Handbook for PCI/Micro Channel