How to remotely turn off all PCs in a laboratory simultaneously?

To remotely turn off all PCs in a laboratory simultaneously, you can use a tool that supports batch or group shutdown commands. Here are some steps you can follow:

1. Determine the network configuration:
   You need to know the network configuration of the laboratory, including the IP addresses of the computers on the network and the operating system running on them.

2. Install a remote shutdown tool:
   There are many remote shutdown tools available, such as SoftPerfect Network Scanner and Remote Shutdown by EMCO. Install the remote shutdown tool on the computer you will be using to issue the shutdown command.

3. Group the computers:
   Group the computers that you want to shut down simultaneously. This can be done in the remote shutdown tool by creating a new group and adding the computers you want to include.

4. Issue the batch shutdown command:
   Once you have grouped the computers, you can issue the batch shutdown command to turn them all off simultaneously. The method for issuing the command will depend on the remote shutdown tool you are using, but typically you will need to select the group you want to shut down and choose the "shutdown" or "power off" option.

5. Confirm the shutdown:
   After issuing the batch shutdown command, you may want to confirm that the computers have shut down properly. You can do this by checking the status of the computers on the network or by using a tool like Ping to confirm that the computers are no longer responding.

Note that turning off computers remotely may cause data loss or other issues, so it is important to ensure that all users have saved their work and closed their programs before initiating a shutdown. It is also important to have appropriate permissions and authorization to shut down all computers on a network.