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5–22
HSG80 Array Controller V8.7 Maintenance and Service Guide
Upgrading the Subsystem
5. Verify that all snapshot units were deleted using the following commands, as
required:
HSGA> SHOW UNITS FULL
IMPORTANT: If any snapshot unit exists, repeat step 4.
6. Identify and record the current CACHE_FLUSH_TIMER value using the
following command:
HSGA> SHOW THIS_CONTROLLER
The following text is only a portion of the resulting display—an arrow points to the
pertinent status indication:
NOTE: The CACHE_FLUSH_TIMER value is displayed in the caching parameters section.
This parameter is modified during the procedure and must be restored later.
7. Set the CACHE_FLUSH_TIMER to 1 second to minimize the flush time, using
the following commands:
HSGA> SET THIS_CONTROLLER CACHE_FLUSH_TIMER=1
HSGA> SET OTHER_CONTROLLER CACHE_FLUSH_TIMER=1
8. Determine if all data has been flushed from the cache module, using the following
command:
HSGA> SHOW THIS_CONTROLLER
The following text is only a portion of the resulting display—an arrow points to the
pertinent status indication:
IMPORTANT: Repeat step 8 on both controllers (THIS_CONTROLLER and
OTHER_CONTROLLER) until no unwritten data remains in either cache module memory.
Cache:
256 megabyte write cache, version 0022
Cache is GOOD
No unflushed data in cache
CACHE_FLUSH_TIMER=DEFAULT (10 seconds)
Cache:
256 megabyte write cache, version 0022
Cache is GOOD
No unflushed data in cache
CACHE_FLUSH_TIMER=1 SECOND