The wdctl command is a utility tool in Linux that shows the status of the hardware watchdog. A hardware watchdog is a timer device that is used to monitor the system for malfunctions or failures. If the watchdog detects a failure or malfunction, it can automatically reset the system or trigger an alarm to alert system administrators.
The wdctl command is used to display information about the current status of the hardware watchdog on the system, including whether it is enabled or disabled, the timeout value, and the current countdown timer value. This information can be useful for system administrators to monitor and troubleshoot the system, especially in situations where the system is not responding or is experiencing unexpected errors or crashes.
The wdctl command can also be used to configure the hardware watchdog, including setting the timeout value, enabling or disabling the watchdog, and configuring other parameters such as the watchdog driver and device file.
The hardware watchdog is commonly used in embedded systems, servers, and other critical systems where high availability and reliability are required. It is typically implemented using a dedicated hardware device or chip that is separate from the main system processor.
wdctl Command Examples
1. Display the watchdog status:
2. Display the watchdog status in a single line in key-value pairs:
# wdctl --oneline
3. Display only specific watchdog flags (list is driver specific):
# wdctl --flags flag_list
Overall, the wdctl command is a useful tool for monitoring and configuring the hardware watchdog on Linux systems, and can be a valuable tool for system administrators and developers working on critical systems. However, it should be used with caution, as misconfigured or improperly used hardware watchdogs can potentially cause system instability or crashes.