Docker-image container Basic operations-common commands

Basic concepts:

• Container

Container. Each container can be viewed as a standalone host. The creation of container usually has an image as its template. Analogy to a virtual machine can be understood as image is the mirror of the virtual machine, and container is a running virtual machine. A virtual machine image can create multiple running virtual hosts and be independent of each other. Note: Once created, container will persist if not removed with the RM command. So remember to delete it when you're done with it.

• Image

Mirror. The image is equivalent to the container template, and after container is created, it depends entirely on what image it uses. Image can be created through container (which is equivalent to saving the state of the container at this time as a snapshot), or by Dockerfile (a text file, which uses some of the Docker-defined notation). The method created by Dockerfile enables the environment configuration and code to be managed together with the repository.

• Registry

The warehouse where the image is stored. As long as you can connect to registry, everyone can easily get a mirror from the repository through the pull command. Docker uses the default repository for Docker hubs, which can be used to build Mirror connected to the Docker hub at home, which speeds up image acquisition. Daocloud

• Boot2docker

A lightweight Linux virtual machine, primarily to make it possible for non-Linux systems to use Docker. It is essentially a VirtualBox virtual host + a command-line tool that can manage this virtual host. Due to the existence of this virtual host, container needs to acquire some physical system resources (such as USB devices) on a non-Linux system, not only to configure the Docker command, but also to configure the resource configuration of the Boot2docker virtual host.

Common Command Table

General:

Operation	Command	Example
View the Docker version	docker version	docker version
View Docker Information	docker info	docker info
View a command Help information	docker help [command]	docker help attach
View Docker Help information	docker --help	docker --help

• Container Related:

Operation	Command	Example
Create container	docker create	docker create chenhengjie123/xwalkdriver
Create and Run container	docker run	docker run chenhengjie123/xwalkdriver /bin/bash
After creating and running container, enter its bash console	docker run -t -i image /bin/bash	docker run -t -i ubuntu /bin/bash
Create and run container and let it run in the background, and port mappings	docker run -p [port in container]:[port in physical system] -d [image] [command]	docker run -p 5000:5000 -d training/webapp python app.py
View all container information that is running	docker ps	docker ps
View the last created container	docker ps -l	docker ps -l
View all container, including the running and closed	docker ps -a	docker ps -a
Outputs the stdout information for the specified container (used to look at log, the effect is similar to tail-f, and is output in real time. ）	docker logs -f [container]	docker logs -f nostalgic_morse
Get container Specify port mapping relationship	docker port [container] [port]	docker port nostalgic_morse 5000
View the list of container processes	docker top [container]	docker top nostalgic_morse
View container More information	docker inspect [container]	docker inspect nostalgic_morse
Stop Continer	docker stop [container]	docker stop nostalgic_morse
Force Stop Container	docker kill [container]	docker kill nostalgic_morse
Start a container that has stopped	docker start [container]	docker start nostalgic_morse
Restart the container (if container is turned off, it starts directly)	docker restart [container]	docker restart nostalgic_morse
Delete Container	docker rm [container]	docker rm nostalgic_morse

When you need to specify container in a command, you can use either its name or its ID.

• Image correlation:

Operation	Command	Example
Create an image from container	docker commit [container] [imageName]	docker commit nostalgic_morse ouruser/sinatra:v2
Create an image from Dockerfile	docker build -t [imageName] [pathToFolder]	docker build ouruser/sinatra:v3 .
View all local image	docker images	docker images
Searching for mirrors in registry	docker search [query]	docker search ubuntu
Get the image from registry (if no tag name is specified, this tag is used by default latest)	docker pull [imageName]	docker pull ubuntu:14.04,docker pull training/webapp
tag to Image	docker tag [imageId] [imageName]	docker tag 5db5f8471261 ouruser/sinatra:devel
Upload local image to registry (this will upload all tags)	docker push [imageName]	docker push ouruser/sinatra
Delete local image	docker rmi [image]	docker rmi training/sinatra

Note: This tag is used by default when the tag name is not specified in the image latest. However, the meaning of latest is not the same as the head of the VCS, it is not the latest image, just the image that represents the tag name latest. If there is no image with the tag name called latest, it will be an error.

Summarize

Although Docker is a virtualization technology, it is more like managing system software or code. Inside, ps top rm commands make it very kind to people who use Linux commands (though their semantics are a little different ...). ),,, start stop restart makes you feel like you're in control of the service, and,, push pull commit , tag makes you feel like you're using Git. So programmers feel very friendly and easy to get started with.

Docker also integrates the operating environment into CI as it can be built using Dockerfile for image, and Docker hub supports automatic building from Dockerfile, such as GitHub.

The drawback is that Docker currently only supports the container technology on Linux, so it has to add one more virtual machine layer to run on a non-Linux system. This will cause some problems that will not occur on Linux (IP address, hardware resources, file mappings, etc.), and because Linux-based, some Windows programs will be acclimatized, more generic than virtual machines.

But the benefit is that the system resources are much lower. A computer that can only open several virtual machines generally can open dozens of container, and the startup time of container is usually within a few seconds, much faster than the virtual machine. In addition, since the image of Docker is essentially an incremental image in addition to some special base mirrors, the repetition does not consume additional resources, so several images that appear to have a number of G will have a repeating portion of the underlying image used (which in most cases will be partially duplicated). Then they will actually occupy much less space.

https://testerhome.com/topics/2760 Common commands: Installing Docker:

• Ubuntu Installation:Image Management

  Docker images: List all local mirrors

  Docker search <image_id/name>: Find Imagedocker pull <image_id>: Download Imagedocker push <IMAGE_ID> : Upload Imagedocker rmi <image_id>: Delete IMAGE container management
  Docker run-i-T <IMAGE_ID>/bin/bash:-i: Standard input to container-T: Assigning a virtual terminal/bin/bash: Execute bash script

  -D: Run as Daemon (background)

  -P: Default matching Docker container's 5000 port number to the host's-P <HOT_PORT>:<CONTAINER_PORT>: Specify port number--name: Specify container name--rm: Delete container on exit
  Docker stop <container_id>: Stop CONTAINER
  Docker start <container_id>: Restart CONTAINER

  -L: Show last started container

  -

  A: Displays the stopped container at the same time, showing only the start status by default

  
  Docker attach <CONTAINER_ID> connect to the boot container docker logs <CONTAINER_ID>  : Output container log

  Docker CP <CONTAINER_ID>:p ath hostpath: Copy the files in the container to the host directory  

  <container_ Id>
  <container_id>: Viewing changes in a container

  <container_id>: View container details (output as JSON)

  -F: Find specific information, such as - ' {{. Networksettings.ipaddress}} '

        Docker commit-m "comment" -a "author" <CONTAINER_ID>  ouruser/imagename:tag
        Docker extc-it <CONTAINER> & Lt COMMAND>: Executes the command in the container and outputs the result  

• Network Management

  Docker run-p: Randomly assigned port number Docker Run-p 5,000:5,000: Bind a specific port number (5000 ports for all network interfaces of the host are bound to 5000 ports of the container) Docker run-p 127.0.0.1:500 0:5,000: Port number of the specific interface of the binding host Docker run-d-P 127.0.0.1:5000:5000/udp training/webapp python app.py: Binding UDP port number Docker port < Container_id> 5000: View the 5000 port of the container corresponding to the IP and port number of the local machine
  To connect containers using Docker linking:

• Docker run-d-P--name web-v/webapp training/webapp python app.py

• You can also attach a container volume to a host directory or a host file,< the contents of the container directory or file > are replaced with the contents of the < host directory or file >, and the default container has read and write access to the directory

  .

   Docker run-d-P--name web-v < host directory >:< container directory > Training/webapp python app.py< /pre> 
   can change permissions to read-only by specifying RO 
   
  -----:< Container directory >:r trainingwebapp python apppy  
   
   Dock Er run-d-v/dbdata--name db1 training/postgres echo data-only container for Postgres 
   
   first starts a container and adds a number to the container According to volume/dbdata, and then start another container, share this data volume 
   
    Docker run  -D--volumes-from db1--name DB2 training/ Postgres  
   
   DB2 uses the DB1 container volume at this time, and when the container DB1 is deleted, the container volume is not deleted, but only if all containers are no longer using the container volume 
   
   Docker RM- V: Delete Container volume 
   

  In addition to sharing data, the container volume is used to back up, restore, and migrate data

  Docker run--volumes-from db1-v/home/backup:/backup ubuntu tar cvf/backup/backup.tar/dbdata

  Start a container data volume using the DB1 container's data volume while creating a new data volume pointing to the host directory/home/backup, compressing the/dbdata directory data to/backup/backup.tar

  docker run -v /dbdata --name dbdata2 ubuntu /bin/bash

  Docker run--volumes-from dbdata2-v/home/backup:/backup busybox tar Xvf/backup/backup.tar

  Start a container and extract the contents of the Backup.tar to the backup of the container

  
  Warehouse Management

  Docker Login: Login

Docker-image container Basic operations-common commands