Forum Discussion
Cirruschecking the fan status on the device.
Understanding how the threshold system works for sensor monitoring on your F5 device is crucial for maintaining the health and performance of the system. The thresholds determine when the system will flag a sensor reading as normal, warning, or critical. Here’s a detailed explanation of how this typically works:
Threshold System Overview
- Sensor Measurement: The system continuously monitors various sensors, such as fan speeds, temperatures, voltages, etc.
- Thresholds: Each sensor has predefined thresholds that specify what values are considered normal, warning, or critical. These thresholds can include:
- Lower Critical (LC): The value below which the sensor reading is considered critical.
- Lower Warning (LW): The value below which the sensor reading is considered a warning.
- Upper Warning (UW): The value above which the sensor reading is considered a warning.
- Upper Critical (UC): The value above which the sensor reading is considered critical.
- Hysteresis: This is a value used to prevent frequent toggling of the sensor status. It creates a buffer zone so that minor fluctuations around the threshold do not cause constant status changes.
Example of Thresholds
For a fan speed sensor:
- LC: 500 RPM (below this is critical)
- LW: 750 RPM (below this is warning)
- UW: 5000 RPM (above this is warning)
- UC: 5500 RPM (above this is critical)
View Current Thresholds:
tmsh show /sys hardware
CumulonimbusHi Zen,
It looks like you've run the system_check -d command on your F5 device and are trying to interpret the results, particularly the Sev (Severity) column, and why all the statuses are marked as CRIT (Critical) even though the current sensor values appear to be normal.
Here's a breakdown of the columns in your table:
- Key: Identifier for the specific sensor being monitored.
- Sys Data: System data associated with the sensor.
- Unit: Measurement unit for the sensor value (e.g., RPM for fan speed, mV for voltage).
- Sta: Status of the sensor (typically 0 indicates normal operation).
- Cur: Current value of the sensor reading.
- Tbl: Table identifier (possibly indicating a group or type of sensor).
- #: Number or identifier for the sensor.
- Type: Type of data being measured (e.g., voltage, fan speed).
- Range: Range of acceptable values for the sensor.
- Value: Current value of the sensor, similar to Cur.
- Hyst: Hysteresis value, indicating the threshold below which the sensor reading would be considered critical.
- Sev: Severity of the current status of the sensor (e.g., I for informational, D for degraded, S for severe, CRIT for critical).
The Sev (Severity) column indicates the current severity status of the sensor. In your case, all the statuses are marked as CRIT (Critical). This is concerning, as it suggests that the system is interpreting the sensor readings as being in a critical state.
There are a few potential reasons why the statuses might be marked as CRIT even though the values appear normal:
- Threshold Settings: The thresholds for what constitutes a critical state might be set incorrectly or too low. You may need to verify and adjust these thresholds in the system configuration.
- Sensor Calibration: The sensors might need calibration. If the sensors are not calibrated correctly, they might report incorrect values leading to false critical alerts.
- Firmware/Software Issue: There might be a bug or issue in the firmware or software that is causing incorrect reporting of sensor statuses. Checking for firmware or software updates could resolve this issue.
- Interpreting Hysteresis: The Hyst value indicates the hysteresis threshold below which the sensor would be considered critical. If the current value is close to this threshold, it might still be marked as critical to prevent rapid switching between states.
To address this, you should:
- Verify Thresholds: Check the configuration for the thresholds of each sensor and adjust them if necessary.
- Consult Documentation: Refer to the F5 documentation for details on interpreting sensor readings and adjusting thresholds.
- Check for Updates: Ensure your device firmware and software are up-to-date.
- Contact Support: If the issue persists, consider reaching out to F5 support for further assistance.
By investigating these areas, you can determine why the statuses are marked as critical and take appropriate action to resolve the issue.
Zen_Ythanks, i'm trying to figure out how the threshold system works.
