Powering on and powering off the clustered system

To power on or to power off the system, complete the steps in this procedure in the order given.

Powering on the system

Attention:

Avoid powering on the system with any open bays or slots. Open bays or slots disrupt the internal air flow, causing the drives to receive insufficient cooling.
Every unused drive bay must be occupied by a filler panel.

To power on the system, complete the following steps:

Power on all expansion enclosures by connecting both power supply units of the enclosure to their power sources, using the supplied power cables.
If the power sources have circuit breakers or switches, ensure that they are turned on. The enclosure does not have power switches. Repeat this step for each expansion enclosure in the system.
Note: Each enclosure has two power supply units. To provide power failure redundancy, connect the two power cords to separate power circuits.
Check the LEDs on each expansion canister as shown in Figure 1.
Figure 1. Expansion canister LEDs
- 1Power
- 2 Status
- 3 Fault
The expansion canister is ready with no critical errors when Power is illuminated, Status is illuminated, and Fault is off. If a canister is not ready, see the troubleshooting procedure about understanding the system status using the LEDs.
Wait for all expansion canisters to finish powering on.
Power on the control enclosure by connecting both power supply units of the enclosure to their power sources, using the supplied power cables.
If the power sources have circuit breakers or switches, ensure that they are turned on. The enclosure does not have power switches.
Note: Each enclosure has two power supply units. To provide power failure redundancy, connect the two power cords to separate power circuits.
Check the LEDs on each node canister in the control enclosure, as shown in Figure 2.
Figure 2. Node canister LEDs
- 1Power
- 2 Status
- 3 Fault
The node canister is ready with no critical errors when Power is illuminated, Status is illuminated, and Fault is off. If a canister is not ready, see the troubleshooting procedure about understanding the system status using the LEDs.

Before you power off the system

To remove all input power to a system (for example, the machine room power must be shut down for maintenance), you must shut down the system before power is removed. Shutting down the system causes all nodes in the system to store data to the internal drive and then enter a standby state. In standby state, volumes provided by the system are no longer accessible.

If the system is not shut down before power to the nodes is turned off, the nodes detect the loss of power and continue to run on battery power until all data that is held in memory is saved to the internal drive.

When input power is restored to the enclosures, the batteries in the nodes recharge. However, the nodes do not permit any I/O activity until the batteries have sufficient charge to enable all the data on the nodes to be saved in the event of an unexpected power loss. This might take as long as two hours if the batteries have been discharged because nodes have run on battery power. Shutting down the system prior to removing input power to the batteries prevents the battery power from being drained and makes it possible for I/O activity to resume as soon as input power is restored.

Powering off the system

To power off your system, complete the following steps:

Stop all host I/O to volumes on the system.
Shut down the system by using the management GUI. Select Monitoring > System. From the Actions menu, select Power Off.
Wait for the power LEDs on all node canisters in all control enclosures to blink at 1 Hz, indicating that the shutdown operation has completed. (See Figure 3 for the location of the power LED.)
Figure 3. Location of the power LED on a node canister
- 1 Power
- 2 Status
- 3 Fault
Disconnect the power cords from both power supplies in each control enclosure.
Disconnect the power cords from both power supplies in each expansion enclosure.