Sun Microsystems StorEdge 3000 Series, Руководство по установке

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Chapter 6 SCSI Module FRUs 6-17
Caution – In a cluster configuration, adding a separate host connection that was not
originally planned for the array will cause a change in SCSI IDs and therefore loses
access to data stored under the original SCSI IDs.
To keep other host connections operational while one host connection is temporarily
removed, perform the following steps.
1. Stop all host I/O activity on the host bus where the removal of a cable will occur.
2. Disconnect the array from the host SCSI cable of the server that requires the
maintenance work from the array.
3. In a dual bus configuration, if two hosts are connected to one bus, and the host
cable to the bottom port of the array is disconnected, move the cable of the top
port to the bottom port.
The moved cable provides termination to the bottom port.
4. Insert the external terminator into the empty top SCSI port on the array.
The external terminator preserves the original SCSI IDs, which are 0 to 5 on each bus
that has two host connections established.
5. Resume host I/O activity on the remaining host(s).
You can have situations in which one or two SCSI cables are temporarily removed from
a standard SCSI array configuration.
FIGURE 6-4
Example of a SCSI Array Configuration
In each of the four scenarios in
FIGURE 6-5
and
FIGURE 6-6
, a single cable was removed
from the original configuration shown in
FIGURE 6-4
. In each of these scenarios one
external terminator was required.
Note –
The bottom input ports support only host SCSI connections and do not
support external terminators.