Now normally if you did not use the nsenter command, the container would be destroyed. After completing this course, you will be able to build applications in a cloud native way using containerization tools. The prompt changes to the bash shell directly when we issue the nsenter command. Sudo nsenter –m –u –n –p –i –t 2978 /bin/bashįrom the output, we can observe the following points − Youre introduced to the concepts of Pods, Clusters, Levels, Services. On chapter two of this ebook, you get to learn all the pieces that makeup Kubernetes. t is used to connect the I/O streams of the container to the host OS.ĬontainerID − This is the ID of the container.Ĭommand − This is the command to run within the container. Whats the difference between Docker and VM, Docker vs Kubernetes, Why you need Kubernetes, Kubernetes use cases all over the world e.t.c Chapter 2: Key definitions and components. i s to make the container run in interactive mode. p is used to mention the process namespace n is used to mention the network namespace m is used to mention the mount namespace Nsenter –m –u –n –p –i –t containerID command Options This method allows one to attach to a container without exiting the container. Now that we have the process ID, we can proceed forward and use the nsenter command to attach to the Docker container. And from the output, we can see that the Process ID is 2978. We then use the Docker inspect command to inspect the configuration of this container and then use the grep command to just filter the Process ID. We can see that there is one running container with the ID of ef42a4c5e663. We can get the Process ID via the Docker inspect command and filtering it via the Pid.Īs seen in the above screenshot, we have first used the docker ps command to see the running containers. It can be done by using the following command −ĭocker run -rm -v /usr/local/bin:/target jpetazzo/nsenterīefore we use the nsenter command, we need to get the Process ID of the container, because this is required by the nsenter command.
One way of achieving this is by using the nsenter command.īefore we run the nsenter command, you need to first install the nsenter image.
Now there is an easier way to attach to containers and exit them cleanly without the need of destroying them.
If we had to exit out of the container directly, then the container itself would be destroyed. In this article, I explain what problems containerization solves and how you can get started using docker today.
We can verify that the container still exists with the Docker ps command. Docker For Dummies Docker is the most popular containerization software in the tech industry. It ensures that the container still exists even after we exit from the container. We used this command to create a new container and then used the Ctrl+P+Q command to exit out of the container. In the above screenshot, you can observe that we have issued the following command − This is what we have seen in the earlier chapters when we were working with containers. By default, when you launch a container, you will also use a shell command while launching the container as shown below.