Owners Manual

PS3000 Series Hardware Maintenance Maintaining Control Modules
3–11
Note: Once connected, a control module cache battery may begin to charge. If
you have a dual control module array and the low-battery-safe cache
policy is enabled (the default), the array will operate in write-through
mode until the cache battery is fully charged.
However, if you need optimal performance before the battery is fully
charged, once the battery status is
good/charging, you can temporarily
disable the low-battery-safe policy and force the array to operate in write-
back mode. Be sure to re-enable the low-battery-safe policy when the
battery is fully charged. See the Group Administration manual for
information about cache policies.
Replacing the Compact Flash Card
Each control module includes a compact flash card running the PS Series array
firmware. There are two reasons why you may need to replace a compact flash
card:
The compact flash card fails on an otherwise functioning control module. Be
sure to order a replacement card with the same firmware version as the failed
card. See Maintaining Control Module Firmware on page 3-4 for information
about identifying firmware.
The control module fails, but the compact flash card is still functioning. If this
occurs, remove the compact flash card from the failed control module and
install the card in the replacement control module. This will ensure that the
new control module is running the correct firmware.
To access the compact flash card, you can remove a control module in a dual
control module array without shutting down the array, if the remaining control
module has at least one connected and functioning network interface. If you
remove the active control module (the LED labeled ACT will be green), there will
be a short interruption as failover to the secondary control module occurs.
Before replacing a compact flash card:
If you have a single control module array, if possible, cleanly shut down the
array before removing the control module. See Shutting Down and Restarting
an Array on page 1-4.
Attach an electrostatic wrist strap, as described in Using an Electrostatic Wrist
Strap on page 1-4.
•See Removing a Control Module on page 3-7 for instructions on removing a
control module.