Batteries

SAN Volume Controller 2145-DH8 and SAN Volume Controller 2145-SV1 nodes contain two batteries that provide backup power to the system when an unforeseen loss of AC power occurs. The battery within a node supplies power only to that node during an unscheduled power loss.

The batteries are connected to the main node. When AC power to the node is interrupted, the system starts to save critical data after a 5-second wait. The backup power protection is then automatically activated. The node receives an uninterrupted supply of power so that it can write cache data and metadata to the disk drives.

If AC power is restored after the system state dump starts, the dump will continue to completion. The node then restarts and rejoins the system. However, if this power is lost for less than 5 seconds, the node remains active in the system and the dump is not started; this process is known as an AC ride-thru.

On SAN Volume Controller 2145-DH8 and SAN Volume Controller 2145-SV1 systems, the canister batteries periodically discharge and charge again to maintain the battery life.

While the node is running, you can remove and install batteries during the following conditions:

• Battery protection is not active and the node is in the Service state. You can check the current state of the node by running the sainfo lsservicestatus command. Both batteries can be swapped in this instance.
• Battery is not discharging or reconditioning. You can check for either state by running the svcinfo lsnodebattery command and checking the charging_status value.

If these conditions are not met and you attempt to remove or install a battery, the node might automatically enter the Service state. If the node is powered by one battery during a full system state dump, the node might shut down.

To determine whether it is safe to remove the battery, enter the following chnodebattery command.

svctask chnodebattery -remove -battery battery_id node_id

If it is not safe to remove the battery, the command fails with a BATTERY_NOT_REDUNDANT error code.

Battery location

The batteries are located in the front of the node. Figure 1 shows the battery locations on a 2145-SV1 node. Each battery has a fault indicator; however, only the fault indicator for battery 2 is shown in the figure.

Figure 1. Location of batteries and indicators on a 2145-SV1 node

•  1  Batteries
•  2  Battery Fault indicator

Figure 2 shows the location of the battery fault and status indicators on a 2145-DH8 node.

Figure 2. Location of batteries, battery fault, and status LEDs on a 2145-DH8 node

•  1  Battery 1
•  2  Battery 2
•  3  Battery Fault LED
•  4  Battery Status LED

If a battery fails, its Battery Fault LED lights. You can identify a battery by using the management GUI or by running the chnodebattery -identify CLI command. The Battery Fault LED flashes on the identified battery.

Each battery has a single LED on its bezel, called the Battery Fault LED. It is lit solid if a fault is on the battery. The LED flashes if the battery is being identified.

Note: A Battery Fault LED that is not lit does not indicate that the battery is actively providing protection. You must run the svcinfo lsnodebattery command to determine protection status.