Linux installation Docker complete and detailed tutorial

Docker has been divided into CE (Community Edition: Community Edition) and EE (Enterprise Edition: Enterprise Edition) since version 17.03. Compared with the community version, the enterprise version emphasizes security, but needs to be paid for. Here we can use the community version.

Docker supports 64-bit versions of CentOS 7 and CentOS 8 and later, and it requires a Linux kernel version no lower than 3.10.

Check the Linux version of the command Here are two recommended: lsb_release -aor cat /etc/redhat-release.

If the system does not support:lsb_release -a 命令，则使用：cat /etc/redhat-release 即可

Check if the kernel version is not lower than 3.10

There are three ways to check the kernel version:

cat /proc/version

uname -a

uname -r

The content version can be viewed in three forms, such as:

It can be seen that the current Linux kernel version meets the requirements of Docker.

Docker automated installation

Docker official and domestic daocloud both provide one-click installation scripts, making Docker installation more convenient.

The official one-click installation method:

curl -fsSL https://get.docker.com | bash -s docker --mirror Aliyun

Domestic daocloud one-key installation command:

curl -sSL https://get.daocloud.io/docker | sh

I have not personally tested the two commands for automated installation. If you are interested, you can test it yourself. I installed Docker manually.

Manual installation of Docker (CentOS7)

Docker is divided into two major versions, CE and EE. CE stands for Community Edition (free, 7-month support period)
EE stands for Enterprise Edition, emphasizing security, paid use, and a support cycle of 24 months.
Docker CE is divided into three update channels: stable test and nightly. There are installation guides in various environments on the official website. Here we mainly introduce the installation of Docker CE on CentOS.
1.1 Uninstall the previous version of Docker

This step is optional. If you have installed an old version of Docker before, you can use the following command to uninstall it. If you have not installed Docker, you can skip this step

yum remove docker \
                  docker-client \
                  docker-client-latest \
                  docker-common \
                  docker-latest \
                  docker-latest-logrotate \
                  docker-logrotate \
                  docker-selinux \
                  docker-engine-selinux \
                  docker-engine \
                  docker-ce

1.2 Install dependent packages

yum-utils provides yum-config-manager, and the device mapper storage driver requires device-mapper-persistent-data and lvm2.

yum install -y yum-utils \device-mapper-persistent-data \lvm2 --skip-broken

1.3 Update the local mirror source (also called: set the source warehouse)

Because docker’s default official image source address is foreign, and the speed is very slow, here the data source is set to the image of Alibaba Cloud. Of course, there are other mirror sources in China.

Alibaba Cloud : http : ** // mirrors.aliyun.com/docker-ce/linux/centos/**docker-ce.repo _

Tsinghua University source: https:**// mirrors.tuna.tsinghua.edu.cn / docker-ce / linux / centos /**docker-ce.repo

yum-config-manager \ --add-repo \ https://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo

1.4 Docker installation

yum install -y docker-ce

The problem arises, after I execute the yum install -y docker-ce command, I get an error: No package docker-ce available.

Tip: No package docker-ce available. It is because I have not uninstalled the old version of Docker

1.4.1 Solution:

Uninstall the old version of docker and its related dependencies

yum remove docker docker-common container-selinux docker-selinux docker-engine

1.4.2 Update yum (this process is a little slow)

yum update

1.4.3 Install yum-utils, which provides yum-config-manager, which can be used to manage yum sources

yum install -y yum-utils

1.4.4 Add yum source, which is equivalent to the command mentioned in [1.3 Update local mirror source]

yum-config-manager --add-repo http://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo

1.4.5 Update index

centos7的命令：
yum makecache fast

centos8的命令：
yum makecache

1.4.6 Execute the install Docker command again

yum install -y docker-ce

1.5 Configuring Mirror Acceleration

The network speed of docker's official mirror warehouse is poor, so we need to set up a domestic mirror service:

Refer to Alibaba Cloud's image acceleration document: Alibaba Cloud Login - Welcome to Alibaba Cloud, a secure and stable cloud computing service platform. Welcome to Alibaba Cloud, the world's leading cloud computing and artificial intelligence technology company. Enterprises, developers and government agencies provide cloud computing basic services and solutions. Alibaba Cloud cloud computing, security, big data, artificial intelligence, enterprise applications, Internet of Things and other cloud computing services. https://cr.console.aliyun.com/cn-hangzhou/instances/mirrors

1.5.1 Create a folder (if the folder already exists, you don’t need to create it)

mkdir -p /etc/docker

1.5.6 Create a deamon.json file in the folder

#在新建的 daemon.json文件中添加内容
[root@wpl docker]# sudo tee /etc/docker/daemon.json <<-'EOF'
> {
>   "registry-mirrors": ["https://akchsmlh.mirror.aliyuncs.com"]
> }
> EOF
{
  "registry-mirrors": ["https://akchsmlh.mirror.aliyuncs.com"]
}

#重新加载文件
[root@wpl docker]# sudo systemctl daemon-reload

#重启docker
[root@wpl docker]# sudo systemctl restart docker

#查看docker运行状态
[root@wpl docker]# systemctl status docker

The result of the execution is shown in the figure below

At this point, the Docker installation is basically complete

Docker start

Command to start Docker:

systemctl start docker

Verify that Docker Engine-Community is installed correctly by running the hello-world image.

// 拉取镜像
docker pull hello-world
// 执行hello-world
docker run hello-world

If after execution, the console displays the following information, it means that Docker is successfully installed and started:

In addition to starting Docker, there are some other startup-related commands:

守护进程重启：
systemctl daemon-reload

重启Docker服务：
systemctl restart docker / service docker restart

关闭Docker服务：
docker service docker stop / docker systemctl stop docker

remove docker

Remove the installation package:

yum remove docker-ce

Delete images, containers, configuration files, etc.:

rm -rf /var/lib/docker

Other common commands of Docker

After installing Docker, here is a summary of common Docker operation commands:

Search warehouse images: docker search image name

Pull image: docker pull image name

View running containers: docker ps

View all containers: docker ps -a

Delete container: docker rm container_id

View mirror: docker images

Delete mirror: docker rmi -f mirror name/mirror ID

Load the image: docker load -i image save file location

Start (stopped) container: docker start container ID

Stop the container: docker stop container ID

Restart the container: docker restart container ID

Start the (new) container: docker run -it ubuntu /bin/bash

Into the container: docker attach 容器IDor docker exec -it 容器ID /bin/bash, the latter is recommended.

View docker status: systemctl status docker

Check the docker version: docker -v

View the directory in the container: docker inspect container ID

More commands can docker helpbe viewed through commands.

Docker settings start automatically at boot

1. View all started services

systemctl list-units --type=service

2. View the set startup services

systemctl list-unit-files | grep enable

Among the services that have been set to start at boot, docker.service cannot be seen.

3. Set the boot to start

systemctl enable docker.service

4. Turn off the boot

systemctl disable docker.service

After executing the command: systemctl enable docker.service, check again to start the service, and you will see docker.service in the list

Docker container settings to start automatically

Add --restart=always when starting

For example : start the mysql service and start it together with docker.

docker run -p 3306:3306 --name mysql --restart=always -v /application/mysql/conf:/etc/mysql/conf.d -v /application/mysql/logs:/logs -v /application/mysql/data:/var/lib/mysql -e MYSQL_ROOT_PASSWORD=123456 -d mysql:5.6

If it has already started, use update to update:

docker update --restart=always 容器id或name

How Docker builds and deploys PHP

The practical operation of this article is to install Docker on Linux. After the installation is completed, it should be applied to the project. How to build and deploy PHP with Docker, please refer to another article I wrote

Docker builds PHP operating environment - Super Le's Blog - CSDN Blog

How to make a Docker image for CI/CD releases.

Making a Docker image, I haven't had time to sort it out, and the follow-up needs to be improved.....