As an IT administrator, it can be helpful to be able to launch a command when a network connection is disconnected or reconnected. This can be especially useful for monitoring network connections and for automating certain tasks. Fortunately, there are a few different ways to do this.
The first method is to use Windows' built-in Network Location Awareness (NLA) service. This service is designed to monitor network connections, and can be configured to run a specific command when a connection is established or disconnected. To use this method, open the Control Panel and navigate to the Network and Internet category. Select the Network and Sharing Center and click on the \Change Adapter Settings\ link. Right-click on the network connection you wish to monitor and select \Properties\ from the context menu. Select the \Configure\ button and switch to the \Advanced\ tab. Scroll down the list of options until you find the \Network Location Awareness\ entry, and enable it. Click the \Settings\ button and enter the command you wish to run when the connection is established or disconnected.
Another method is to use a third-party monitoring tool such as PRTG Network Monitor or SolarWinds Network Performance Monitor. These tools provide much more comprehensive network monitoring capabilities than the Windows NLA service. They can be configured to run a command when a connection is established or disconnected.
Finally, you can use the Windows Task Scheduler to launch a command when a connection is established or disconnected. To do this, open the Windows Task Scheduler and create a new task. Select the \Run when a specific event is logged\ option and select the \Network\ event log. Select the \Connection Established\ or \Connection Terminated\ event and set the task to run the desired command when this event is logged.
These are the three main methods for launching a command when a network connection is established or disconnected. Each of these methods has its own advantages and disadvantages, and the best one for you will depend on your particular needs. However, all of these methods can be useful for automating certain tasks or monitoring network connections.