Docker installation and use

Docker installation and use

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Docker 中文 版,docker help,docker manual,docker tutorial,docker installation manual – docker中文 版) ()

What is the docker

Docker is a container virtualization technology that solves the running environment and configuration problems of the software container, facilitating continuous integration and contributing to the overall release

Why docker

The environment

1. The virtual machine

Centos7.7, the vm installed by yourself is not ali cloud

2. View the system version command

lsb_release -a
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Execute the following command if the command execution above prompts that the command was not found

yum install -y redhat-lsb
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3. View and disable the firewall

systemctl status firewalld
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systemctl stop firewalld
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Install the docker

1. Install the tool package

sudo yum install -y yum-utils
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Or perform

yum update
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Wait for a long time

2. Configure the remote vault

sudo yum-config-manager --add-repo https://download.docker.com/linux/centos/docker-ce.repo
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3. Install the docker

sudo yum install docker-ce
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4. Start the docker

Start the

service docker start
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stop

service docker stop
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restart

service docker restart
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Check the version

Docker version/docker - vCopy the code

Join open start

chkconfig docker on
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5. A charm

docker run hello-world
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6. Basic docker commands

View all running containers

docker ps
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View all containers that are running, including those that failed to start

docker ps -a
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Remove the container

Docker RM Container name/container IDCopy the code

If the container is running, you need to stop the container to delete it

Stop the container

Docker stop Container IDCopy the code

View all mirrors

docker images
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Remove the mirror

Docker RmI IMAGE name /IMAGE IDCopy the code

Forcibly Deleting a Mirror

Docker image rm -f Image name/image IDCopy the code

Deleting all Mirrors

As shown below, I pulled three images

docker images
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Get the IMAGE ids of all images

docker images -qa
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Deleting all Mirrors

docker rmi $(docker images -qa)
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Check again, it’s gone

docker images
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Delete all containers

You can run the docker ps-qa command to query the ids of all containers, then run the docker stop (dockerps− QA) command to stop all containers, then run the dockerrm command to stop all containers, and then run the Docker rm command to stop all containers Run the dockerps−qa command to close all containers, and then run the dockerrm(docker ps-qa) command to delete all containers

The following example shows how to delete all mirrors, as shown in the figure below, and encounters the following problems

To resolve the problem, run the following command

Delete container ID The container ID (d652B36931F5 in the figure above) occupied by docker rm or forcibly delete the docker image rm -f Image name/image ID

Configure Ali Cloud accelerator

1. Log in to Aliyun Developer Platform

[Ali Cloud login – welcome to Ali Cloud, a secure and stable cloud computing service platform (aliyun.com)](cr.console.aliyun.com/cn-hangzhou…)

2. Set the password upon your first login

3. Obtain the acceleration address

https://********.mirror.aliyuncs.com

4. Select the DOCker OS according to personal needs, and modify the Docker configuration file according to installation requirements. I use centos here, and the steps are as follows

Create a daemon.json file

In the/etc/docker/directory file new daemon. Json, vim editor/etc/docker/daemon. Json file add the following content

{ "registry-mirrors": ["https://*******.mirror.aliyuncs.com"]}Copy the code

Save and exit, then restart the Docker

systemctl daemon-reloadsystemctl restart docker
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Or run the following command once

sudo mkdir -p /etc/dockersudo tee /etc/docker/daemon.json <<-'EOF' { "registry-mirrors": ["https://hmchwtyi.mirror.aliyuncs.com"] } EOF sudo systemctl daemon-reload sudo systemctl restart docker
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Check the startup status of docker

service docker status
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In the future, it will be much faster to obtain the required image through the Docker pull command than to download it directly from the official website

Docker install tomcat

1. Obtain the Tomcat image

Search the mirror

docker search tomcat
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Pull the mirror

docker pull tomcat
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The speed will be much faster after the aliyun accelerator is configured

Specify version pull

Docker pull tomcat: 8.0.53Copy the code

[Docker Hub](hub.docker.com/) (super slow) search you need…

2. View all mirrors

docker images
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REPOSITORY: represents the REPOSITORY source of the image

TAG: indicates the TAG of the mirror

IMAGE ID: indicates the ID of an IMAGE

CREATED: indicates the time when a mirror is CREATED

SIZE: indicates the mirror SIZE

3. Run the container

docker run --name tomcat -p 8080:8080 -v $PWD/test:/usr/local/tomcat/webapps/test -d tomcat
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Parameter interpretation

A) -p 8080:8080: maps port 8080 of the container to port 8080 of the host

B) – v $PWD/test: / usr/local/tomcat/webapps/test: the host of the current directory in the test/test mounted to the container

Access test 192.168.0.192:8080

4. If there are two versions of Tomcat, see the following figure

At run time, you need to specify a TAG to run, and it is best to use an alias to distinguish them to avoid confusion

Docker run - name mytomcat (alias) - p (designated port 8081) : 8081-8080 v $PWD/test: / usr/local/tomcat/webapps/test - d Tomcat :8.0.53 (specified TAG)Copy the code

5. Deploy the WAR package

Into the container

docker exec -it NAME/ CONTAINER ID bash
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Upload the WAR package to any directory

/home/liucong/tomcat

Run cp command

Then execute in the directory where the war package resides:

docker cp datamgt.war tomcat:/usr/local/tomcat/webapps
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Move the WAR package under WebApps in the Tomcat container

Go into the container to see if datamgt.war exists

Go into the container to see if datamgt.war exists

The WAR package shown above will automatically decompress, exit the container, and then execute the command to restart the container

docker restart tomcat
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View container logs in the last 30 minutes

docker logs --since 30m tomcat
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Browser access

http://192.168.0.192:8081/datamgt/treesoft/login

Docker mysql installation

1. Search for the version you want to pull from the official website

Mysql5.7.28 will be installed by default if no version is specified

docker pull

Docker pull mysql: 5.7.28Copy the code

Run the container

docker run -p 3306:3306 --name mysql -v /home/mysql/conf:/etc/mysql/conf.d -v /home/mysql/logs:/logs -v / home/mysql/data: / var/lib/mysql - e MYSQL_ROOT_PASSWORD = rootroot - d mysql: 5.7.28Copy the code

-p 3306:3306: Maps port 3306 of the container service to port 3306 of the host. The external host can directly access the MySQL service through host IP address 3306

-v: mounts the host directory to the container for data synchronization

MYSQL_ROOT_PASSWORD=rootroot: Set the password of user root of the mysql service

Check whether the installation is successful: Docker PS, as shown below, starts tomcat and mysql containers

Enter the mysql container and log in to mysql

sudo docker exec -it mysql /bin/bash
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Enter the password set above

2. Use a tool to connect

Upload the local Docker image to Ali Cloud image warehouse

1. Log in to the Aliyun image repository

Ali Cloud login – Welcome to Ali Cloud, a secure and stable cloud computing service platform (aliyun.com)

Enter the Ali Cloud container image service console, and set the password for the first time, as shown in the following figure

Currently the control does not have any private images, as shown below

Create a mirror repository as shown in the following figure

Set the namespace, repository name, private or public, if it’s public then everyone can search for the image you uploaded

Run the following command to log in to the Aliyun image warehouse

docker login [email protected] registry.cn-hangzhou.aliyuncs.com
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The password is the previous one. The login is successful, as shown in the following figure

2. View the image to be uploaded

docker images
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3. Push the image we need to upload

As shown below, wait patiently (feel super slow, is the mirror too big? Bad Internet?)

Docker tag ef6a7c98d192 registry.cn-hangzhou.aliyuncs.com/liucong/tomcat:8.0.53Copy the code

Sudo docker push registry.cn-hangzhou.aliyuncs.com/liucong/tomcat:8.0.53Copy the code

4. Upload successfully, as shown below, ali Cloud image service console will exist

5. If the image is set to public, it will be searched by others. Otherwise, set it to private

6. Pull the image we just uploaded from another server and start the Tomcat service

Now use another server (192.168.0.191) to install the Docker, and then pull the image. Please refer to the steps above. No more mapping will be repeated here

First login Ali cloud mirror service

sudo docker login [email protected] registry.cn-hangzhou.aliyuncs.com
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Then execute the pull command:

Sudo docker pull registry.cn-hangzhou.aliyuncs.com/liucong/tomcat:8.0.53Copy the code

The version number is consistent with that of Ali Cloud mirroring service

Look at mirror

docker images
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Run the image

docker run --name tomcat -p 8080:8080 -v $PWD/test:/usr/local/tomcat/webapps/test -d ef6a7c98d192
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Into the container

docker exec -it CONTAINER ID bash
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access

http://192.168.0.191:8080/

Docker container data volume

1. What is the container data volume

When we use docker container, a series of data files will be generated. These data files will disappear when we close docker container, but part of the content generated in it we hope to be able to save it for another purpose. Docker will package the application and the running environment into a container and publish it. We want some of the data generated by the running process clock to be persistent, and we want to be able to share data between containers.

Generally speaking, docker container data volume can be regarded as a USB disk commonly used in our life. It exists in one or more containers and is mounted to the container by Docker, but it does not belong to the joint file system. Docker will not delete the mounted data volume when the container is deleted

2. What are its features

A) Data volumes can share or reuse data before containers

B) Changes in data volumes can take effect directly

C) Changes in the data volume are not included in the update of the mirror

D) The life cycle of a data volume continues until no container can use it

3. There are two ways to add a data volume

Mount by command (synchronizes even after the container exits)

• First of all by

  docker pull centos 
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  Pull a centos image, the following shows the way to mount by command

• Execute the command

  docker run -d -it -v /home/mycentosdata:/mycentos centos
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  Docker run – d (background, otherwise after exit containers, container will stop) – it – v/hosting an absolute path: / container mirror directory name/image ID

  This command creates two directories on the host and in the container. The two directories are connected and the data in the two directories can be shared

  

• Check whether the mount is successful

  Run ls -ll in the container to see that the mycentos folder has been generated

  

  Looking at the host’s home directory, myCentosData is also generated

  

• View with command

  Docker inspect Container IDCopy the code

  

  After this command is executed, a JSON string will be returned. Because it is too long to attach here, only part of the screenshot will be attached, as shown in the following figure, indicating that the mount is successful

  

• Create a new file a.toxt in myCentosData, and mycentos in the container will be generated accordingly, as shown in the figure below

  Docker exec it 9f55d0ebb0e4 /bin/bashCopy the code

  

  

  Even after stopping the container, it will be shared, so I won’t do the demo here, but try it out

  Add it as a Dockerfile

  Note: Using Dockerfile will not generate the corresponding directory, but will also generate a default file, as shown below

  • In order to standardize, I created a docker folder in the root directory of the host and created a Dockerfile file, and added the following content

    FROM centos
    VOLUME ["/mydockerfiledata"."/mydockerfiledata1"]  -- privileged=true
    CMD echo "success build"
    CMD /bin/bash
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    It is equivalent to running the docker run it -v/host directory path: / Directory path image name

  • Docker build and docker commit can be used to build docker images. Docker commit needs to be done inside the container,docker build does not need to be done.

    Docker build -f '/docker/DockerFile' -t liucong/centosCopy the code

    docker build -f  '/docker/DockerFile' -t liucong/centos .
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    The following figure indicates that the compilation is successful

    

    docker images
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    Command, as shown in the following figure, there are two centos images

    

  • Run liucong/centos mirroring: Mount the /home/mycentosdata directory to the two newly generated directories by using commands

    docker run -d -it -v /home/mycentosdata:/mydockerfiledata liucong/centos
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    Use Dockerfile to mount the default folder on the host, as shown in the following figure

    use

    Docker inspect 978edCF8F273Copy the code

    View mounting information

    The following figure shows all mounted folders Host machine and the corresponding container mounted directory, last step I not manual will be hosting/home/mycentosdata mounted to the inside of the container/mydockerfiledata directory, so below corresponding relationship of the first show is so, but we use Dockerfile mydocker The fileData1 directory does not use a command to specify a mount directory, so one is assigned by default

    

4. Read and write permissions

 docker run -d -it -v /home/centosdata:/centosdata:ro centos
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If ro is not included in the command, the file in the container can be read and written

Ro indicates that the files in the container are read-only, as shown in the following figure

Docker inspect FAe237C35C06Copy the code

First create a new a.txt variable in the host directory to write content, and then enter the container to see if it can be edited, as shown below

Readonly files

Docker data volume container

The so-called data volume container, in plain English, is the active hard disk hanging on the active hard disk, the realization of data transfer dependence

1. The following mirror liucong/centos created in the previous step is a template and runs containers LC01 / LC02 / LC03

   

2. In order to distinguish between the two, I have deleted all the files that were previously mounted in the host and container. I will create a new mount directory lc01 and create a new file lc01.txt in the mount directory

   docker run -d -it --name lc01 -v /home/docker/lc01:/lc01 liucong/centos
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   TXT file is created in /home/docker-lc01 directory of the host computer. The content of the file is create LC01

   

   As shown below, the data has been synchronized to the container

   ​

3. The above new LC01 container, so how to achieve the dependency of data transfer, see the following steps

   Then create lc02 container and inherit LC01 to implement data transfer. If successful, then lc01. TXT created in mount directory will also appear in lc02 container

   docker run -d -it --name lc02 --volumes-from lc01 liucong/centos
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   As shown in the following figure, LC02 is created successfully. Now let’s enter lc02 container to check whether lc01.txt is stored

   

   

   If we create lc02.txt on the host, then lc01 and LC02 will be synchronized

   

   As shown in the above image, we have created lc02txt in the host mount directory and edited it to create LC02. Now let’s see if the two containers are synchronized

   

   

   As shown in the figure above, lc01 and LC02 both exist in LC02.txt, it seems that the data transfer is successful, so the new LC03 container is the same, there is no map here

   Since new can be shared with data passing, deletion must be synchronized. If lc01 is deleted, does the data from lc02, which inherits LC01, still exist?

   Take a look at the picture below

   

   The conclusion: Still there

4. Delete all data container volumes

   docker volume rm $(docker volume ls -q)
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   To stop and remove containers before delete data volume, otherwise you will be prompted data volume is being used to remove failure, found a problem, is through the command starts and create data volume of container, the container delete again after operation, the previously created data volume, and created by way of Dockerfile data volume, will always exist