Which command can be used to stop a running container?

Which command can be used to stop a running container?

• A. docker halt [container_id]
• B. docker stop [container_id]
• C. docker pause [container_id]
• D. docker kill [container_id]

Answer: (B)

The command "docker stop [container_id]" is designed specifically to stop a running container in a graceful manner. When invoked, it sends a SIGTERM signal to the main process running inside the container, allowing it to shut down cleanly and finish any ongoing tasks. After a default timeout period (which can be adjusted), if the container does not stop, Docker then sends a SIGKILL signal to forcibly terminate the container if necessary. In contrast, other commands serve different purposes. For instance, while "docker kill [container_id]" also stops a container, it does so immediately by sending a SIGKILL signal without waiting for the container to shut down gracefully. "docker halt [container_id]" is not a valid command within Docker's CLI for managing containers. "docker pause [container_id]" is used to pause a running container, temporarily suspending all processes in that container rather than stopping it altogether. Given this context, the command that best fits the requirement to stop a running container, allowing for a clean shutdown, is "docker stop [container_id]."

The command "docker stop [container_id]" is designed specifically to stop a running container in a graceful manner. When invoked, it sends a SIGTERM signal to the main process running inside the container, allowing it to shut down cleanly and finish any ongoing tasks. After a default timeout period (which can be adjusted), if the container does not stop, Docker then sends a SIGKILL signal to forcibly terminate the container if necessary.

In contrast, other commands serve different purposes. For instance, while "docker kill [container_id]" also stops a container, it does so immediately by sending a SIGKILL signal without waiting for the container to shut down gracefully. "docker halt [container_id]" is not a valid command within Docker's CLI for managing containers. "docker pause [container_id]" is used to pause a running container, temporarily suspending all processes in that container rather than stopping it altogether.

Given this context, the command that best fits the requirement to stop a running container, allowing for a clean shutdown, is "docker stop [container_id]."