What should I do if the docker process cannot be stopped?

Docker is an open source containerization technology that has been widely used in cloud computing, microservices and DevOps fields. It significantly simplifies application deployment and management by allowing developers to build and deploy applications by creating, running, and managing containers.

However, when using Docker, some users may encounter the problem that the process cannot be stopped. This article will delve into the root cause of the problem and provide some effective solutions.

Problem phenomenon

When using Docker, sometimes we will find that the process in the Docker container cannot be stopped. Specifically, after using the docker stop or docker kill command, the process in the container is not killed, and the container status is still running.

After many attempts using the docker stop and docker kill commands, the process still cannot be ended, leaving the user very confused.

Cause of the problem

The reason for this problem is actually very simple: the process in the Docker container is likely to be managed by the Supervisor process. In this case, if you use the docker stop or docker kill command to terminate the container, only the Supervisor process will be stopped, not the process itself. That's why you will find that the container status is still running.

Solution

1. Learn to use ps to view process information

In order to solve the problem that the Docker process cannot be stopped, we need to learn to use the ps command to view process information . In a Docker container, use the ps command to view the currently running process. The specific command is as follows:

docker exec -it [CONTAINER_ID] ps aux

where CONTAINER_ID is the ID of the container, use the docker ps command to obtain it.

2. Use kill to terminate the process directly

After we determine the process PID on the Supervisor process, we can use the kill command to directly terminate the process. The specific command is as follows:

docker exec -it [CONTAINER_ID] kill [PID]

where PID is the PID of the process, obtained through the ps command.

3. Configuring the Supervisor configuration file

If you want to more thoroughly solve the problem of the Docker process not being able to stop, then we need to configure the Supervisor process configuration file in the Docker container Add the following options:

stopasgroup=true
killasgroup=true

These two options can ensure that the Supervisor process and all processes under it can be completely killed when executing the docker stop or docker kill command.

In the Supervisor configuration file, you can add options through the following command:

[program:program_name]
command=/path/to/program
stopasgroup=true
killasgroup=true

where program_name is the program name and /path/to/program is the path of the program.

Finally, just restart the Supervisor process in the Docker container.

4. Use docker-compose to start the container

In addition to the above method, you can also use docker-compose to start the Docker container and add the kill command to terminate all processes in the container to avoid The process cannot be stopped.

version: '3'
services:
  your_service:
    build: .
    command: ["tail", "-f", "/dev/null"]
    stop_signal: SIGKILL

In this docker-compose file, we use the SIGKILL signal to terminate all processes within the container.

Summary

The inability to stop the Docker process is a common problem, but the solution is relatively simple. We can solve the problem by using the ps command to view process information, using the kill command to directly terminate the process, configure the Supervisor configuration file, or use docker-compose to start the container and add the kill command.

No matter which method is used, you can solve the problem that the Docker process cannot be stopped and ensure the normal operation of your Docker container.

The above is the detailed content of What should I do if the docker process cannot be stopped?. For more information, please follow other related articles on the PHP Chinese website!