You can determine the system status by using the LED indicators on a control enclosure.
To understand the status of the I/O port at the rear of a control enclosure, refer to Node canister indicators.
Status indicators on the front of a control enclosure are described in Components in the front of the enclosure.
A detailed view of the system state is provided in the Monitoring sections of the management GUI and by the service assistant. If the management GUI and the service assistant are not accessible, you can use the LED indicators on the control enclosures to determine the system status.
The system status LEDs visible at the rear of each control enclosure can show one of several states, as described in Table 1.
| 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, 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, off for 250 ms, and then repeats. |
| Blinking fast | The LED turns on and off at a frequency of 4 Hz: It is on for 125 ms, 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. |
Complete the following steps to understand when a node canister is not participating in the system, and what remedial action to take.
- If at least one PSU is providing power to a control enclosure, use Table 3 to check the
status of each node canister in that enclosure.
Table 2. Power supply unit LEDs LED state Action Fault (amber)
AC power (green)
DC power (green)
On (any) (any) The power supply unit must be replaced. Follow the steps that are described in Replacing a power supply unit. Off On On The power supply is functioning normally, providing power to the enclosure. Off The power supply unit must be replaced. Follow the steps that are described in Replacing a power supply unit. Off On The power supply unit must be replaced. Follow the steps that are described in Replacing a power supply unit. Off The power supply is not receiving power from the power outlet through the power cord. To power on the system, connect the power supply to an outlet by using the power cord and turn on the power outlet. Note: The fourth status LED on the power supply unit is not used.Table 3. Node canister status LEDs LED state Description Power (green)
System status (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. Follow Procedure: Reseating a node canister to reseat any node canister in this state. If the condition persists, follow Replacing a node canister if just one canister is affected, or Replacing a control enclosure midplane if both canisters are affected.
Blinking slowly Power is available, but the canister is powered off. The main CPU is not running.
To restart the node canister, follow Procedure: Reseating a node canister.
Blinking fast The node canister is performing self test during startup.
Wait for the canister to complete its startup sequence.
On Off Off The node canister is in standby mode. The system software is not running.
It is safe to remove or reseat the canister.
To restart the node canister, follow Procedure: Reseating a node canister.
Blinking The node canister is in candidate state. The node is not performing I/O in the system.
Unless indicated by the battery status LED (see Table 4), it is safe to remove or reseat the canister.
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 need to recover the system or create a new system.
Blinking fast A code update is in progress.
The canister must not be removed. No user action is required.
On The system software is running, and the node canister is participating in the system. The LED state indicates normal system operation.
The canister must not be removed.
Off Blinking 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 was activated. To determine whether 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. Blinking fast The Identify function for this canister was activated. A code update is in progress.
The canister must not be removed.
On The Identify function for this canister was activated.
To determine whether 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.
Off On 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 by following Procedure: Reseating a node canister. If the canister still shows this fault, follow Replacing a node canister.
Blinking The node is in service state. It is safe to remove or reseat the canister.
Refer to Table 4 to determine whether the battery charge is insufficient.
Use the service assistant to identify any node errors or refer to Procedure: Fixing node errors to determine what to do.
If the node is able to communicate with the configuration node, there might also be an error alert in the system event log. In this case, you should run the associated fix procedure.
Blinking fast The node is in service state.
A code update is in progress. The canister must not be removed.
No action is required until the code update completes.
On The system software is running. However, the event log might contain an alert, 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. Otherwise, refer to the service actions for node error 550.
Table 4. Node canister battery status LEDs LED state Description Fault (amber)
Battery in use (green)
Battery status (green)
On (any) (any) The battery in the node canister must be replaced. Follow the steps that are described in Replacing the battery in a node canister.
Off Blinking fast (any) The canister detected an interruption in DC power and is using the battery to perform an emergency shutdown operation, saving critical data to the system drive.
Do not remove the canister from the enclosure. Restore power to the enclosure.
When power to the enclosure is restored, the canister resumes operation when the battery is sufficiently charged.
Off 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.
Blinking fast The node canister is charging its battery, perhaps after it repeatedly performed emergency shutdown operations. The current charge level is insufficient to complete one emergency shutdown operation.
The node reports a node error, forcing it into service state while the battery continues to charge.
Wait for the battery to charge. The canister resumes operation when the battery is sufficiently charged.
On The battery is optimally charged, such that the 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.