IBM SAN256B-6, Installation, Service And User Manual

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WWN Cards
This topic provides the following information:
v “WWN card overview”
v “Precautions specific to WWN cards” on page 150
v “WWN card fault indicators” on page 150
v “WWN card replacement task guide” on page 151
v “Time and items required for replacement” on page 152
v “Using the wwnrecover utility” on page 152
v “Preparing for WWN card replacement” on page 153
v
“Hot-swap replacement” on page 154
v “Cold-swap replacement” on page 156
v “Removing the WWN card and bezel” on page 157
v “Configuring airflow direction on WWN cards” on page 158
v “Verifying WWN card operation” on page 160
WWN card overview
Two WWN cards are located behind the WWN bezel between the power supplies on the nonport side of
the device. WWN 1 is located on the left side and WWN is located on the right side. The WWN cards
store critical configuration data, such as WWN, IP addresses, part and serial numbers, and license IDs for
the device.
Identical data must be maintained on each WWN card at all times so that if one card fails, the system can
use the other card to provide valid system operation. To maintain data and ensure its integrity, the
system audits both WWN cards one hour after the first system boot-up, every 24 hours after boot-up, and
any time a WWN card is inserted to compare the critical data.
If a data mismatch is detected during the audit, messages in the RASlog will provide a summary of all
errors detected and prompt you through a data recovery process. The
wwnrecover
utility permits a
recovery of WWN card data in the event of corruption. The data recovery mechanism may vary
depending on the error encountered and the data being compared. Problems such as a mismatch between
license IDs cannot be fixed with
wwnrecover , and the output will direct you to call Technical Support. For
other problems, running wwnrecover can pinpoint the problem and, in some cases, permit you to fix it.
Mismatched data can be resolved, and corrupt data can sometimes be recovered. For more information
on the
wwnrecover utility, refer to “Using the wwnrecover utility” on page 152.
Note: The device will operate with one WWN card, but will be in degraded condition. If you have
removed a card, be sure to replace as soon as possible.
WWN Location Numbering
WWN card are located behind the WWN bezel on the nonport side of the device between the power
supplies. The bezel must be removed to access the card trays. The following figure illustrates WWN card
location and numbering.
© Copyright IBM Corp. 2018
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