Appendix H. Control Switch Settings Work Sheet - IBM DS8800 Introduction And Planning Manual

Appendix H. Control switch settings work sheet

Complete the control switch settings work sheet to indicate whether to enable or
disable a particular switch setting. Your DS8000 model can include one or more
storage images; consequently, you many need to indicate your individual choice
for each.
The switch settings described in this section can be enabled or disabled by
indicating your choices on the work sheet that follows the setting descriptions.
IBM service personnel use the choices you specify on the work sheet to set the
control switches for your unit.
IBM i LUN serial suffix number
Use the IBM i LUN serial suffix number switch setting only when you attach more
than one DS8000 series model to an AS/400 or IBM i host and the last three digits
of the worldwide node name (WWNN) are the same on any of the DS8000 units.
For example, the WWNN for the first DS8000 is 500507630BFFF958 and the
WWNN for an additional DS8000 is 500507630AFFF958. Both DS8000 units would
present the same LUN serial number for the same LUN ID. Because the original
LUN serial number is used for identification, the AS/400 does not use the LUN
from the additional DS8000. Specifying a unique serial number base for the
additional DS8000 unit prevents this problem. IBM service personnel enter the
control-switch setting for the new serial number base, which you specify for this
field.
The WWNN can be found on the WWID label on the inside front left wall of rack
one, located near the LED indicators of the upper-primary power supply. For
example, WWID: 500507630AFFF99F.
Notes:
v The probability of receiving two DS8000 series models with the same last three
v After updating the switch settings, a quiesce and resume of the storage facility
The IBM i LUN serial suffix number applies to IBM i and AS/400 environments
only.
Control-unit Initiated reconfiguration settings
The control-unit initiated reconfiguration (CUIR) setting indicates whether to
enable or disable subsystems. CUIR prevents loss of access to volumes in System z
environments due to incorrect path handling. This function automates channel
path management in System z environments, in support of selected DS8000 service
actions. CUIR relies on a combination of host software and DS8000 firmware. The
host systems are affected during host adapter repair or I/O enclosure repair. The
CUIR setting on the work sheet enables you to indicate whether this option can be
enabled. The CUIR setting applies to IBM System z and S/390 environments only.
© Copyright IBM Corp. 2004, 2012
WWNN digits is unlikely, but possible.
image is required for the changes to take effect.
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