Write-Back Versus Write-Through Cache Options; Accessing The Management Tools - Sun Microsystems StorEdge 3000 Series Installation, Operation And Service Manual

Note – The RAID controller has a temperature sensor which shuts off battery
charging above 54 degrees C. When this happens, the battery status may be reported
as BAD, but no alarm is written to the event log since no actual battery failure has
occurred. This behavior is normal. As soon as the temperature returns to the normal
range, battery charging resumes and the battery status is reported correctly. It is not
necessary to replace or otherwise interfere with the battery in this situation.
For information on the date of manufacture and how to replace the battery module,
refer to the Sun StorEdge 3000 Family FRU Installation Guide.
For more information, see
acceptable operating and non-operating temperature ranges for your array.
5.4 Write-Back Versus Write-Through Cache
Options
Unfinished writes are cached in memory in write-back mode. If power to the array is
discontinued, data stored in the cache memory is not lost. Battery modules can
support cache memory for several days.
Write cache is not automatically disabled when the battery is offline due to battery
failure or a disconnected battery. You can enable or disable the write-back cache
capabilities of the RAID controller. To ensure data integrity, you may choose to
disable Write Back cache option and switch to the Write Through cache option
through the firmware application (go to "view and edit Configuration parameters"
and select "Caching Parameters"). The risk of data loss is remote.
5.5

Accessing the Management Tools

You can manage the array through one of the following three methods:
With the out-of-band serial port connection, you can use a Solaris tip session or
I
a Windows terminal emulation program to access the firmware application. For
details, refer to
page
With the out-of-band Ethernet port connection, you can use telnet to access the
I
firmware application. For details, refer to
Over Ethernet" on page
"Environmental Requirements" on page 2-3
"Configuring a COM Port to Connect to a RAID Array" on
4-23.
4-25.
"Setting Up Out-of-Band Management
Chapter 5 First-Time Configuration
for the
5-5