Procedure: Understanding the system status from the LEDs

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To determine the system status by using the LED indicators on a control enclosure, use this procedure.

About this task

The system status LEDs, which are visible on the front end cap of each control enclosure, can show one of several states, as described in Table 1.

A detailed view of the system state is provided in the Monitoring sections of the management GUI and by the service assistant. If neither the management GUI nor the service assistant is accessible, use this procedure to determine the system status by using the LED indicators on the control enclosures.

Table 1. LED state descriptions used in the control enclosure
State description Detail
Off The LED is continuously not lit.
Blinking slowly The LED turns on and off at a frequency of 1 Hz. It is on for 500 ms, then off for 500 ms, and then repeats.
Blinking The LED turns on and off at a frequency of 2 Hz. It is on for 250 ms, then off for 250 ms, then repeats.
Blinking fast The LED turns on and off at a frequency of 4 Hz. It is on for 125 ms, then off for 125 ms, and then repeats.
On The LED is continuously lit.
Flashing The LED is lit to indicate some activity, then turns off. The rate and duration that the LED is lit depends on the rate and duration of the activity.

Procedure

Complete the following steps to understand when a node canister is not participating in the system, and what remedial action to take.

  1. Identify the control enclosures for the system you are troubleshooting.
  2. Use the following table to check the status of each power supply unit (PSU) in a control enclosure.
    Understanding the power supply unit LEDs
    Indicator Color Meaning
    Power supply status Green
    • Off - The enclosure is not receiving AC power; ensure that the power is turned on.
    • On - The power supply is receiving AC power; no action is required.
    • Slow flash - AC is present. However, check the Event Log for errors, such as a possible fan failure.
    • Flashing - The power supply firmware is being updated. No actions are required; do not remove AC power.
    Amber A fault needs to be resolved.
    • Slow flash - The power supply is on, but needs maintenance. Check the Event Log for errors and events where the power supply continues to operate, such as high temperature, high power, high current, or slow fan.
    • On - AC power is lost or the cable is unplugged, but power is still being supplied from the second power supply. There might also be a critical fault in the power supply that causes it to shut down (such as a fan failure). Check that the AC power cable is plugged and power is provided. If the amber LED persists, check the Event Log.
  3. If at least one PSU is providing power to a control enclosure, use Table 2 to check the status of each node canister in that enclosure.
    Table 2. Understanding the node canister status LEDs
    LED state System status (green) Description
    Power (green) Fault (amber)
    Off (any) (any) Power is not being provided by any power supply unit (PSU) in the enclosure, or power is coming from the battery in the canister.

    If at least one PSU is powering the enclosure, the canister or the enclosure midplane might be faulty.

    If both node canisters in an enclosure indicate this state at the same time, it is more likely that the enclosure midplane is faulty. Reseat any node canister in this state.

    Blinking slowly Power is available, but the canister is powered off. The main CPU is not running.

    Restart the node canister.

    Blinking fast The node canister is doing a self test during start-up.

    Wait for the canister to complete its start-up sequence.
    On Off Off The node canister is in standby mode. The system software is not running.

    Restart the node canister.

    Blinking The node canister is in candidate state. The node is not doing I/O in the system.
    Unless indicated by the battery status LED, it is safe to remove or reseat the canister. See Table 3.

    If the node state is candidate and the system is running on the other node canister, the candidate node is automatically added to the system.

    If both node canisters are in candidate state, determine whether you must recover the system or create a new system.
    Blinking fast The node is doing an emergency shutdown operation, using the battery for power, after detecting a loss of power from the power supply units.

    Wait for the emergency shutdown operation to complete. If the partner node has also done an emergency shutdown operation, there was most likely a loss of input power to both enclosure power supply units and the system restarts when the input power is restored. Otherwise, there might be a fault the node canister, enclosure midplane, or power supply units.
    On The system software is running, and the node canister is participating in the system.

    The canister must not be removed.

    This is the normal operational LED state.
    On Blinking Off The node canister is in standby mode. The system software is not running.

    It is safe to remove or reseat the canister.
    Blinking The Identify function for this canister has been activated. To determine if it is safe to remove the canister, use the management GUI or service assistant to turn off the Identify function, then check the node canister status LEDs again.
    On Blinking Blinking fast The Identify function for this canister has been activated.

    The node is doing an emergency shutdown operation, using the battery for power, after detecting a loss of power from the power supply units.

    Wait for the emergency shutdown operation to complete. If the partner node has also done an emergency shutdown operation, there was most likely a loss of input power to both enclosure power supply units and the system restarts when the input power is restored. Otherwise, there might be a fault in the power supply units or the node canister.
    On Blinking On The Identify function for this canister was activated.

    To determine if it is safe to remove the canister, use the management GUI or service assistant to turn off the Identify function, then check the node canister status LEDs, again.
    On On Off The system software is not running. The BIOS might have detected a fault.

    It is safe to remove or reseat the canister.

    Try reseating the canister. If the canister still shows this fault, replace the node canister.

    On On Blinking The node is in service state. It is safe to remove or reseat the canister.
    See Table 3 to determine whether the battery charge is insufficient.

    Use the service assistant to identify any node errors or to determine what to do, see Procedure: Fixing node errors.

    If the node is able to communicate with the configuration node, there might also be an error alert in the system event log, in which case you should run the associated fix procedure.
    On On Blinking fast The node is in service state.

    There is a code update in progress.

    The canister must not be removed.

    No action is required until the code update completes.
    On On On The software is running but there might be an error alert in the event log, such as error code 550.

    The canister must not be removed.

    If possible, go to the management GUI and run the fix procedure for the error alerts listed there. If this is not possible, refer to the service actions for node error 550.
    Table 3. Understanding the node canister battery status LEDs
    LED state Description
    Fault (amber) Status (green)
    On On A battery fault exists that caused the node canister to do an emergency shutdown operation (storing its cache data to the system disk). The node canister is in service state or is going into service state. The service assistant shows a node error.

    Replace the battery in the node canister.

    On Off A battery fault exists that caused the node canister to shut down to service state. There was insufficient power in the battery or the supply for the node canister to do an emergency shutdown operation. The service assistant shows a node error.

    Replace the battery in the node canister.

    Off Blinking fast The battery is charging and has insufficient charge to protect against a single AC loss. The node is held in service state with a fatal node error until the battery has charged.
    Blinking The battery has sufficient charge to complete one emergency shutdown operation.

    This state does not prevent the canister from participating in the system.

    The battery continues to charge until it is able to complete two emergency shutdown operations. No action is necessary.
    On The battery is optimally charged, such that the node canister is able to complete two emergency shutdown operations.

    This state does not prevent the canister from participating in the system. The canister continues to manage the battery charge.

    No action is necessary.
  4. Repeat these steps for each control enclosure in the system.