Planning: RAID Controller Modules 35
System Password Reset
The storage array system password can be reset if it is forgotten. To reset the
password, push and hold down the password reset switch for at least 5
seconds. The password is deleted. See Figure 3-1 to locate the password reset
switch.
The RAID controller module allows you to change the password. For more
information about setting your password, see "Setting a Password" on page 69.
NOTE: The reset switch can be accessed by using a small object such as the tip of
a pen.
Cache Functions and Features
Cache Mirroring
Cache mirroring function copies accepted host-write data from the primary
controller to the partner controller. This action ensures that host-write data is
safely mirrored to the partner controller before successful completion status is
returned to the host. If a controller fails, the surviving controller safely retains
all mirrored data. Cache mirroring is enabled by default.
Write-Back Cache
In Write-back Cache, write operations result in a completion signal being
sent to the host operating system as soon as the cache receives the data to be
written. The target physical disk receives the data at a more appropriate time
in order to increase controller performance. In dual-active controller
configurations with Write-back Caching enabled, the write data is always
Table 3-1. Shutdown Threshold Type
Threshold Temperature Exceeding Event Description
Nominal failure threshold A critical event is set
Maximum failure threshold Shutdown of the system power supplies occurs
within three minutes
Shutdown threshold Shutdown of the system power supplies occurs
within five seconds
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