Docker的安装与卸载、启动与停止

Docker的概述
Docker的安装前提
Docker的安装
Docker的卸载
Docker的启动与停止

Docker的概述

Docker 是一个开源的应用容器引擎。

Docker 让开发者可以打包他们的应用以及依赖包到一个可移植的镜像中，然后发布到任何流行的 Linux或Windows 机器上，也可以实现虚拟化。

Docker 容器是完全使用沙箱机制，相互之间不会有任何接口。

Docker 从 17.03 版本之后分为 CE（Community Edition: 社区版）和 EE（Enterprise Edition: 企业版）

三个重要概念

1.image镜像

docker镜像就是一个只读模板，比如，一个镜像可以包含一个完整的centos，里面仅安装apache或用户的其他应用，镜像可以用来创建docker容器，另外docker提供了一个很简单的机制来创建镜像或者更新现有的镜像，用户甚至可以直接从其他人那里下载一个已经做好的镜像来直接使用

2.container容器

docker利用容器来运行应用，容器是从镜像创建的运行实例，它可以被启动，开始、停止、删除、每个容器都是互相隔离的，保证安全的平台，可以把容器看做是简易版的linux环境（包括root用户权限、镜像空间、用户空间和网络空间等）和运行再其中的应用程序

3.repostory仓库

仓库是集中存储镜像文件的沧桑，registry是仓库主从服务器，实际上参考注册服务器上存放着多个仓库，每个仓库中又包含了多个镜像，每个镜像有不同的标签（tag）

仓库分为两种，公有参考，和私有仓库，最大的公开仓库是docker Hub，存放了数量庞大的镜像供用户下周，国内的docker pool，这里仓库的概念与Git类似，registry可以理解为github这样的托管服务

Docker的安装前提

Docker 运行在 CentOS 7 上，要求系统为64位、系统内核版本为 3.10 以上。

Docker 运行在 CentOS-6.5 或更高的版本的 CentOS 上，要求系统为64位、系统内核版本为 2.6.32-431 或者更高版本。

Docker的安装

1.查看系统内核版本是否满足

执行命令：uname -r

[root@master ~]# uname -r
3.10.0-1062.4.1.e17.x86_64

2.确保 yum 包更新到最新。

yum update

3.安装需要的软件包， yum-util 提供yum-config-manager功能，另外两个是devicemapper驱动依赖的

yum install -y yum-utils  
yum install -y device-mapper-persistent-data
yum install -y  lvm2
	
yum install -y yum-utils device-mapper-persistent-data lvm2

4.设置yum源为阿里云，提高下载速度,避免出现其他异常情况

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

5.可以查看所有仓库中所有docker版本，并且可以选择特定版本安装

 yum list docker-ce --showduplicates | sort -r
 
 yum install <FQPN>  # 例如： yum install docker-ce-3:19.03.9-3.el7

6.安装docker,默认最新稳定版

yum install docker-ce

7.安装后查看docker版本

执行命令：docker -v

[root@master ~]# docker -v
Docker version 19.03.11,bu11d 42e35e61f3

8.设置国内镜像源，提高拉取docker镜像速度

登录阿里云控制台查看专属的镜像加速地址,并按照其提示进行修改

首先创建目录/etc/docker，然后执行命令：vi /etc/docker/daemon.json ，输入配置内容。

[root@master ~]# mkdir /etc/docker
[root@master ~]# touch /etc/docker/daemon.json
[root@master ~]# vim /etc/docker/daemon.json

{ 		"registry-mirrors":["https://u6gcz43x.mirror.aliyuncs.com"] 		}

常见的国内镜像源:

1. Docker中国区官方镜像 https://registry.docker-cn.com

2.网易 http://hub-mirror.c.163.com

3.ustc  https://docker.mirrors.ustc.edu.cn

4.中国科技大学 https://docker.mirrors.ustc.edu.cn

5.阿里云容器  服务 https://cr.console.aliyun.com/

重启Docker

1、centOS7.0使用

systemctl daemon-reload
systemctl restart docker

2、centOS7.0以下

service docker restart

Docker的卸载

查看docker状态：

systemctl status docker

[root@master ~]# systemctl status docker
● docker.service - Docker Application Container Engine
   Loaded: loaded (/usr/lib/systemd/system/docker.service; disabled; vendor preset: disabled)
   Active: active (running) since Mon 2022-08-01 08:14:12 UTC; 11s ago
     Docs: https://docs.docker.com
 Main PID: 74220 (dockerd)
    Tasks: 8
   Memory: 44.0M
   CGroup: /system.slice/docker.service
           └─74220 /usr/bin/dockerd -H fd:// --containerd=/run/containerd/containerd.sock

停止docker：

systemctl stop docker

查询安装docker的文件包

yum list installed | grep docker

删除所有安装docker的文件包

yum -y remove '包名'

删除卷/网络内容/镜像/容器等，默认在/var/lib/docker目录

rm -rf /var/lib/docker

[root@master ~]# ls /var/lib/docker
buildkit  containers  image  network  overlay2  plugins  runtimes  swarm  tmp  trust  volumes

Docker的启动与停止

Linux 服务管理两种方式service和systemctl

systemd是Linux系统最新的初始化系统(init)命令

systemctl命令是系统服务管理器指令

启动docker：

systemctl start docker

查看docker状态：

systemctl status docker

停止docker：

systemctl stop docker

重启docker：

systemctl restart docker

开机启动：

systemctl enable docker

查看docker概要信息

docker info

[root@master ~]# docker info
Client:
 Context:    default
 Debug Mode: false
 Plugins:
  app: Docker App (Docker Inc., v0.9.1-beta3)
  buildx: Docker Buildx (Docker Inc., v0.8.2-docker)
  scan: Docker Scan (Docker Inc., v0.17.0)

Server:
 Containers: 0
  Running: 0
  Paused: 0
  Stopped: 0
 Images: 0
 Server Version: 20.10.17
 Storage Driver: overlay2
  Backing Filesystem: xfs
  Supports d_type: true
  Native Overlay Diff: true
  userxattr: false
 Logging Driver: json-file
 Cgroup Driver: cgroupfs
 Cgroup Version: 1
 Plugins:
  Volume: local
  Network: bridge host ipvlan macvlan null overlay
  Log: awslogs fluentd gcplogs gelf journald json-file local logentries splunk syslog
 Swarm: inactive
 Runtimes: runc io.containerd.runc.v2 io.containerd.runtime.v1.linux
 Default Runtime: runc
 Init Binary: docker-init
 containerd version: 10c12954828e7c7c9b6e0ea9b0c02b01407d3ae1
 runc version: v1.1.2-0-ga916309
 init version: de40ad0
 Security Options:
  seccomp
   Profile: default
 Kernel Version: 4.18.0-372.16.1.el8_6.x86_64
 Operating System: Red Hat Enterprise Linux 8.6 (Ootpa)
 OSType: linux
 Architecture: x86_64
 CPUs: 2
 Total Memory: 776.6MiB
 Name: master
 ID: 6RPI:GTBV:YHHB:3MSH:7UKS:UN46:5PMQ:EIQO:3C6T:GFG2:TDKV:QMEA
 Docker Root Dir: /var/lib/docker
 Debug Mode: false
 Registry: https://index.docker.io/v1/
 Labels:
 Experimental: false
 Insecure Registries:
  127.0.0.0/8
 Registry Mirrors:
  https://u6gcz43x.mirror.aliyuncs.com/
 Live Restore Enabled: false

查看docker帮助文档

docker --help

[root@master ~]# docker --help

Usage:  docker [OPTIONS] COMMAND

A self-sufficient runtime for containers

Options:
      --config string      Location of client config files (default "/root/.docker")
  -c, --context string     Name of the context to use to connect to the daemon (overrides DOCKER_HOST env var and default context set with "docker context use")
  -D, --debug              Enable debug mode
  -H, --host list          Daemon socket(s) to connect to
  -l, --log-level string   Set the logging level ("debug"|"info"|"warn"|"error"|"fatal") (default "info")
      --tls                Use TLS; implied by --tlsverify
      --tlscacert string   Trust certs signed only by this CA (default "/root/.docker/ca.pem")
      --tlscert string     Path to TLS certificate file (default "/root/.docker/cert.pem")
      --tlskey string      Path to TLS key file (default "/root/.docker/key.pem")
      --tlsverify          Use TLS and verify the remote
  -v, --version            Print version information and quit

Management Commands:
  app*        Docker App (Docker Inc., v0.9.1-beta3)
  builder     Manage builds
  buildx*     Docker Buildx (Docker Inc., v0.8.2-docker)
  config      Manage Docker configs
  container   Manage containers
  context     Manage contexts
  image       Manage images
  manifest    Manage Docker image manifests and manifest lists
  network     Manage networks
  node        Manage Swarm nodes
  plugin      Manage plugins
  scan*       Docker Scan (Docker Inc., v0.17.0)
  secret      Manage Docker secrets
  service     Manage services
  stack       Manage Docker stacks
  swarm       Manage Swarm
  system      Manage Docker
  trust       Manage trust on Docker images
  volume      Manage volumes

Commands:
  attach      Attach local standard input, output, and error streams to a running container
  build       Build an image from a Dockerfile
  commit      Create a new image from a container's changes
  cp          Copy files/folders between a container and the local filesystem
  create      Create a new container
  diff        Inspect changes to files or directories on a container's filesystem
  events      Get real time events from the server
  exec        Run a command in a running container
  export      Export a container's filesystem as a tar archive
  history     Show the history of an image
  images      List images
  import      Import the contents from a tarball to create a filesystem image
  info        Display system-wide information
  inspect     Return low-level information on Docker objects
  kill        Kill one or more running containers
  load        Load an image from a tar archive or STDIN
  login       Log in to a Docker registry
  logout      Log out from a Docker registry
  logs        Fetch the logs of a container
  pause       Pause all processes within one or more containers
  port        List port mappings or a specific mapping for the container
  ps          List containers
  pull        Pull an image or a repository from a registry
  push        Push an image or a repository to a registry
  rename      Rename a container
  restart     Restart one or more containers
  rm          Remove one or more containers
  rmi         Remove one or more images
  run         Run a command in a new container
  save        Save one or more images to a tar archive (streamed to STDOUT by default)
  search      Search the Docker Hub for images
  start       Start one or more stopped containers
  stats       Display a live stream of container(s) resource usage statistics
  stop        Stop one or more running containers
  tag         Create a tag TARGET_IMAGE that refers to SOURCE_IMAGE
  top         Display the running processes of a container
  unpause     Unpause all processes within one or more containers
  update      Update configuration of one or more containers
  version     Show the Docker version information
  wait        Block until one or more containers stop, then print their exit codes

Run 'docker COMMAND --help' for more information on a command.

To get more help with docker, check out our guides at https://docs.docker.com/go/guides/