Docker common command description

Usage: docker pull [OPTIONS] NAME[:TAG]

# docker pull centos
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Before docker v1.2, you could download all the official images in the centos repository. Will pull the centos:latest image, its intermediate layers and any aliases of the same ID, That is, only images with the latest tag (and other tags with the same image ID) will be downloaded. You can also specify a specific mirror:

# docker pull centos:centos6
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Docker pull username/repository<:tag_name> :

# docker pull seanlook/centos:centos6
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If you don’t have a network, or from other private servers to get the mirror, like docker pull registry.domain.com: 5000 / repos: < tag_name >

# docker pull dl.dockerpool.com:5000/mongo:latest
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The Docker run command first creates a writable container layer from a specific image and then starts it with the start command. A stopped Container can be restarted and retain the original changes. There are a lot of the run command to start the parameters, below is some general instructions, more parts please refer to www.cnphp6.com/archives/24… When docker run is used to create containers, the standard operations that Docker runs in the background include:

• Check whether the specified image exists locally and download it from the public repository if it does not
• Create and start a container with an image
• Assign a file system and mount a read-write layer outside the read-only mirror layer
• Bridge a virtual interface from the host host’s configured bridge interface to the container
• Configure an IP address from the address pool to the container
• Execute the user-specified application
• The container is terminated after execution

Usage: docker run [OPTIONS] IMAGE [COMMAND] [ARG...]

5.1 Using image to create a Container, run the corresponding command, and stop the container

# docker run ubuntu echo "hello world"
hello word
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This is the easiest way to do it, and it hardly feels any different from simply executing echo ‘Hello World’ locally, when in fact it will start from the local Ubuntu: Latest image to a container, execute the print command and exit (docker ps -l can be viewed). Note that there is a default –rm=true parameter, which stops the container and removes it from the file system. Because Docker containers are so lightweight, most of the time users delete and create containers at any time. After the CONTAINER is started, it automatically generates a CONTAINER ID, which can be changed to an IMAGE ID after the commit command is executed

Create a container using image and enter interactive mode. The login shell is /bin/bash

# docker run -i -t --name mytest centos:centos6 /bin/bashBash - 4.1 -#
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The –name argument above can specify the name of the container after startup, otherwise Docker will pick a name for us. Centos: Mirror centos can also use IMAGE ID (68edf809afe7), and will start a dummy terminal, but we can only see one or two processes through ps or top command, because the core of the container is the application being executed, and the resources required are necessary for the application to run. In addition, there are no other resources, which shows that Docker has a very high utilization rate of resources. After exit or Ctrl+D, the container will disappear. Which TAG will be used to start images with different tags and the same IMAGE ID

5.2 Running a Container To Run in the Background

# docker run -d ubuntu /bin/sh -c "while true; do echo hello world; sleep 2; done"
ae60c4b642058fefcc61ada85a610914bed9f5df0e2aa147100eab85cea785dc
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It will suspend the started Container and run it in the background (this is called saas). It will output a Container ID, and you can see the container information through Docker PS. Docker logs AE60C4B64205 can also be attached to the running terminal by Docker attach AE60c4B64205. At this point, when Ctrl+C exits the container, the container disappears. Press Ctrl-p ctrl-q to exit the host while the Container is still running. In addition, if -d starts but the following commands stop, such as /bin/bash or echo test, the Container will still terminate when it is finished. And -d cannot be used with –rm. You can run memcached, Apache, etc.

5.3 Mapping host Ports and Directories to Containers

It is useful to map the host to the container’s port. For example, if you run memcached in a Container on port 11211, the host running the container can connect to internel_IP :11211 of the container. If you need to access memcached from another host, you can use the -p option, such as -p

, in the following ways:

-p 11211:11211 this is the default, To bind port 11211 of all network adapters on a host (0.0.0.0) to port 11211 of a container, run the following command: -p 127.0.0.1:11211:11211 To bind only port 11211 of interface localhost -p 127.0.0.1::5000 -p 127.0.0.1:80:8080Copy the code

In fact, directory mapping is to “bind and mount” the host path to the directory of container, which is convenient for transferring files inside and outside. In the section of private server building, in order to prevent images saved after private server container stops being deleted, submitted images should be saved to the mounted host directory. -v

is easy to use. If multiple directories are bound, add -v.

-v /tmp/docker:/tmp/docker
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Alternatively, you can establish a link between two Containers -link, as described in the advanced section or official documentation. Here’s an example:

# docker run --name nginx_test \> - v/TMP/docker: / usr/share/nginx/HTML: ro \ > p - 80-80 - d \ > nginx: 1.7.6Copy the code

Create index.html under/TMP /docker on the host and you can access it at http://localhost:80/ or http://host-ip:80.

A container can run a new one using run or restart a stopped container, but start cannot specify the instructions to run when the container is started, because docker can only have one foreground process. When the container stops (or Ctrl+D), it exits after saving the current state of the container, and the next time it starts, it keeps the changes it made when it was last closed. And the attach screen is the same every time you enter it, the same as when the first run started or when the commit was committed.

CONTAINER_ID=$(docker start <containner_id>)
docker stop $CONTAINER_ID
docker restart $CONTAINER_ID
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These commands can be used with a complete example of how Docker creates a container that runs a daemon and provides a shell terminal.

Inspect objects can be an image, a running Container, or a stopped Container.

View the internal IP of the container# docker inspect --format='{{.NetworkSettings.IPAddress}}' $CONTAINER_ID
172.17.42.35
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The build command can create an image from a Dockerfile and context: Docker build [OPTIONS] PATH | | – the above URL PATH or URL of the file is called the context, the build process of the image will look over these documents transmitted to the server of a docker. If the PATH is a separate Dockerfile, you don’t need the context; If the URL is a Git repository address, Git will clone a copy of the image to a local temporary directory during the image creation process, which becomes the context for the build. No matter what PATH is specified, the Dockerfile is essential, see the Dockerfile Reference. Look at the following example:

# cat Dockerfile 
FROM seanlook/nginx:bash_vim
EXPOSE 80
ENTRYPOINT /usr/sbin/nginx -c /etc/nginx/nginx.conf && /bin/bash
 
# docker build -t seanlook/nginx:bash_vim_Df .Sending build context to Docker daemon 73.45MB Sending build context to Docker daemon Step 0: FROM seanlook/nginx:bash_vim ---> aa8516fa0bb7 Step 1 : EXPOSE 80 ---> Using cache ---> fece07e2b515 Step 2 : ENTRYPOINT /usr/sbin/nginx -c /etc/nginx/nginx.conf && /bin/bash ---> Runningin e08963fd5afb
 ---> d9bbd13f5066
Removing intermediate container e08963fd5afb
Successfully built d9bbd13f5066
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The PATH above is., so all files in the current directory (except.dockerignore) will be tarred and sent to the Docker Daemon (usually on the local machine), from which we can send build Context… And finally, to remove an Intermediate container, you can keep the container by –rm=false. To-do docker build github.com/creack/docker-firefox failed.

The docker ps command displays the CONTAINER ID, NAME, IMAGE NAME, port start and binding, and COMMNAD executed after the CONTAINER is started. You can always find CONTAINER_ID using Photoshop. Docker ps -l docker ps -l docker ps -l docker ps -l docker ps -l

Docker also has some less common commands, such as login, cp, logs, export, import, load, kill, etc., which are relatively simple, please refer to the official website.