[系统运维]docker基础用法

一、Docker是什么？

《Docker开发实践》中讲了个故事：20世纪60年代以前的海运，货物都放置在一起，很容易挤压受损。同时，不同的运输方式之间的转运也很麻烦，例如从码头和火车汽车转运卸货时。不同货物和不同交通工具之间的组合是一个巨大的二维矩阵。海运界最后达成了一致，制定了国际标准集装箱来解决这个棘手的问题。所有货物都打包进集装箱互相隔离，所有交通工具都通过集装箱转运，极大地提供了运输的安全性和效率。

在软件开发中我们也经常碰到同样的问题，使用了各种各样技术框架的应用程序，从前端静态网站到后端数据库，从PHP到Java，以及多种多样的部署环境，从测试服务器到线上环境，从虚拟机到公有云等等。Docker，正是这个集装箱，而Docker的logo也的确是个集装箱。

二、Docker与容器和虚拟机

很自然地我们会问，Docker跟虚拟机有什么区别啊？这个问题可以拆成两部分。因为Docker并不是什么完全独创的技术，而是属于很早便有了的容器技术，所以第一个问题就是容器与虚拟机的区别？同属于容器技术，Docker的兄弟姐妹还有Solaris Zones、BSD jails、LXC等。但Docker现在这么火，自然有它的独到之处，所以第二个问题就是Docker与其他容器的区别？

关于第一个问题比较简单，容器是一种轻量级的虚拟技术。它不像虚拟机那样具有一套完整的CPU、内存和磁盘，对操作系统有绝对的权限。容器和宿主主机共享内核，所有容器共享操作系统，在一台物理机上可以运行成百上千的容器。第二个问题稍麻烦一些，与LXC相比，Docker对配置进行了抽象，使应用在任何平台上的运行环境都一致。同时提供了版本控制、镜像托管等类似Git的现代化设施和生态圈。

总体来看，Docker的应用场景有：

• 加速本地开发：快速搭建好开发环境和运行环境
• 自动打包和部署应用
• 创建轻量级的私有Paas环境
• 自动化测试和持续集成
• 创建安全沙盒

三、OCI&OCF

3.1 OCI

Open Container-initiative（开源的容器的一个建议或倡导）

• 由Linux基金会主导于2015年6月创立

• 旨在围绕容器格式和运行时制定一个开放的工业化标准

• contains two specifications

  • the Runtime Specification（runtime-spec）
  • the Image Specification（image-spec）

3.2 OCF

开源的容器的格式
runC是一个命令行工具，是用于根据OCI规范生成和运行容器

• 容器作为runC的子进程启动，可以嵌入到各种其他系统中，而无需运行守护进程
• runC构建在libcontainer上，这项容器技术为数百万Docker引擎安装提供了动力

docker提供了一个专门容纳容器镜像的站点：https://hub.docker.com/

四、docker架构

五、docker镜像与镜像仓库

为什么镜像仓库名字是Registry而不是repository？在docker中仓库的名字是以应用的名称取名的。

镜像是静态的，而容器是动态的，容器有其生命周期，镜像与容器的关系类似于程序与进程的关系。镜像类似于文件系统中的程序文件，而容器则类似于将一个程序运行起来的状态，也即进程。所以容器是可以删除的，容器被删除后其镜像是不会被删除的。

六、docker对象

使用docker时，您正在创建和使用图像、容器、网络、卷、插件和其他对象。

• 镜像

  • 镜像是只读模板，其中包含创建docker容器的说明。
  • 通常，一个镜像基于另一个镜像，并进行一些额外的自定义。
  • 您可以创建自己的镜像，也可以只使用其他人创建并在registry中发布的镜像。

• 容器

  • conntainer是镜像的可运行实例。 您可以使用docker API或CLI创建、运行、停止、移动或删除容器。
  • 您可以将容器连接到一个或多个网络，将存储连接到容器，甚至可以基于其当前状态创建新镜像。

七、安装及使用docker

7.1 docker安装

环境：centos 7.5

[root@localhost ~]# cd /etc/yum.repos.d/
[root@localhost yum.repos.d]# ls
CentOS-Base.repo       CentOS-fasttrack.repo  CentOS-Vault.repo
CentOS-CR.repo         CentOS-Media.repo
CentOS-Debuginfo.repo  CentOS-Sources.repo
[root@localhost yum.repos.d]# curl -o docker-ce.repo https://mirrors.tuna.tsinghua.edu.cn/docker-ce/linux/centos/docker-ce.repo
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
  0     0    0     0    0     0      0      0 --:--:-- --:--:-- --:-100  1919  100  1919    0     0   3806      0 --:--:-- --:--:-- --:--:--  3815
[root@localhost yum.repos.d]# ls
CentOS-Base.repo       CentOS-fasttrack.repo  CentOS-Vault.repo
CentOS-CR.repo         CentOS-Media.repo      docker-ce.repo
CentOS-Debuginfo.repo  CentOS-Sources.repo
[root@localhost yum.repos.d]# sed -i 's@https://download.docker.com@https://mirrors.tuna.tsinghua.edu.cn/docker-ce@g' docker-ce.repo
[root@localhost yum.repos.d]# yum clean all
[root@localhost yum.repos.d]# yum makecache
[root@localhost ~]# yum -y install docker-ce

7.2 docker加速

docker-ce的配置文件是/etc/docker/daemon.json，此文件默认不存在，需要我们手动创建并进行配置，而docker的加速就是通过配置此文件来实现的。

docker的加速有多种方式：

• docker cn（特别慢）
• 中国科技大学加速器
• 阿里云加速器（需要通过阿里云开发者平台注册帐号，免费使用个人私有的加速器）
  https://cr.console.aliyun.com/cn-hangzhou/instances/mirrors

[root@localhost ~]# systemctl enable --now docker
Created symlink from /etc/systemd/system/multi-user.target.wants/docker.service to /usr/lib/systemd/system/docker.service.
[root@localhost ~]# ls /etc/docker/
key.json
[root@localhost ~]# tee /etc/docker/daemon.json <<-'EOF'
> {
>   "registry-mirrors": ["https://2bkybiwf.mirror.aliyuncs.com"]
> }
> EOF
{
  "registry-mirrors": ["https://2bkybiwf.mirror.aliyuncs.com"]
}
[root@localhost ~]# cat /etc/docker/daemon.json 
{
  "registry-mirrors": ["https://2bkybiwf.mirror.aliyuncs.com"]
}
[root@localhost ~]# docker info
Client:
 Context:    default
 Debug Mode: false
 Plugins:
  app: Docker App (Docker Inc., v0.9.1-beta3)
  buildx: Build with BuildKit (Docker Inc., v0.6.3-docker)
  scan: Docker Scan (Docker Inc., v0.9.0)

Server:
 Containers: 0
  Running: 0
  Paused: 0
  Stopped: 0
 Images: 0
 Server Version: 20.10.11
 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: 7b11cfaabd73bb80907dd23182b9347b4245eb5d
 runc version: v1.0.2-0-g52b36a2
 init version: de40ad0
 Security Options:
  seccomp
   Profile: default
 Kernel Version: 3.10.0-862.el7.x86_64
 Operating System: CentOS Linux 7 (Core)
 OSType: linux
 Architecture: x86_64
 CPUs: 2
 Total Memory: 1.779GiB
 Name: localhost.localdomain
 ID: BYNG:CDGP:V62W:5NS4:CQPZ:ZCHU:N2YY:DMF6:CDVT:WMOJ:ZQW4:D7IP
 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
 Live Restore Enabled: false

[root@localhost ~]# systemctl daemon-reload
[root@localhost ~]# systemctl restart docker
[root@localhost ~]# docker info
Client:
 Context:    default
 Debug Mode: false
 Plugins:
  app: Docker App (Docker Inc., v0.9.1-beta3)
  buildx: Build with BuildKit (Docker Inc., v0.6.3-docker)
  scan: Docker Scan (Docker Inc., v0.9.0)

Server:
 Containers: 0
  Running: 0
  Paused: 0
  Stopped: 0
 Images: 0
 Server Version: 20.10.11
 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: io.containerd.runc.v2 io.containerd.runtime.v1.linux runc
 Default Runtime: runc
 Init Binary: docker-init
 containerd version: 7b11cfaabd73bb80907dd23182b9347b4245eb5d
 runc version: v1.0.2-0-g52b36a2
 init version: de40ad0
 Security Options:
  seccomp
   Profile: default
 Kernel Version: 3.10.0-862.el7.x86_64
 Operating System: CentOS Linux 7 (Core)
 OSType: linux
 Architecture: x86_64
 CPUs: 2
 Total Memory: 1.779GiB
 Name: localhost.localdomain
 ID: BYNG:CDGP:V62W:5NS4:CQPZ:ZCHU:N2YY:DMF6:CDVT:WMOJ:ZQW4:D7IP
 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://2bkybiwf.mirror.aliyuncs.com/     重启之后，这里就会有一个加速器
 Live Restore Enabled: false

[root@localhost ~]# docker version
Client: Docker Engine - Community
 Version:           20.10.11
 API version:       1.41
 Go version:        go1.16.9
 Git commit:        dea9396
 Built:             Thu Nov 18 00:38:53 2021
 OS/Arch:           linux/amd64
 Context:           default
 Experimental:      true

Server: Docker Engine - Community
 Engine:
  Version:          20.10.11
  API version:      1.41 (minimum version 1.12)
  Go version:       go1.16.9
  Git commit:       847da18
  Built:            Thu Nov 18 00:37:17 2021
  OS/Arch:          linux/amd64
  Experimental:     false
 containerd:
  Version:          1.4.12
  GitCommit:        7b11cfaabd73bb80907dd23182b9347b4245eb5d
 runc:
  Version:          1.0.2
  GitCommit:        v1.0.2-0-g52b36a2
 docker-init:
  Version:          0.19.0
  GitCommit:        de40ad0

7.3 docker常用操作

• docker search → 在Docker Hub中搜索镜像

[root@localhost ~]# docker search nginx
NAME                              DESCRIPTION                                     STARS     OFFICIAL   AUTOMATED
nginx                             Official build of Nginx.                        15899     [OK]       
jwilder/nginx-proxy               Automated Nginx reverse proxy for docker con…   2098                 [OK]
richarvey/nginx-php-fpm           Container running Nginx + PHP-FPM capable of…   819                  [OK]
jc21/nginx-proxy-manager          Docker container for managing Nginx proxy ho…   285                  
linuxserver/nginx                 An Nginx container, brought to you by LinuxS…   160                  
tiangolo/nginx-rtmp               Docker image with Nginx using the nginx-rtmp…   146                  [OK]
jlesage/nginx-proxy-manager       Docker container for Nginx Proxy Manager        144                  [OK]
alfg/nginx-rtmp                   NGINX, nginx-rtmp-module and FFmpeg from sou…   110                  [OK]
nginxdemos/hello                  NGINX webserver that serves a simple page co…   79                   [OK]
privatebin/nginx-fpm-alpine       PrivateBin running on an Nginx, php-fpm & Al…   60                   [OK]
nginx/nginx-ingress               NGINX and  NGINX Plus Ingress Controllers fo…   57                   
nginxinc/nginx-unprivileged       Unprivileged NGINX Dockerfiles                  54                   
nginxproxy/nginx-proxy            Automated Nginx reverse proxy for docker con…   28                   
staticfloat/nginx-certbot         Opinionated setup for automatic TLS certs lo…   25                   [OK]
nginx/nginx-prometheus-exporter   NGINX Prometheus Exporter for NGINX and NGIN…   22                   
schmunk42/nginx-redirect          A very simple container to redirect HTTP tra…   19                   [OK]
centos/nginx-112-centos7          Platform for running nginx 1.12 or building …   16                   
centos/nginx-18-centos7           Platform for running nginx 1.8 or building n…   13                   
flashspys/nginx-static            Super Lightweight Nginx Image                   11                   [OK]
mailu/nginx                       Mailu nginx frontend                            9                    [OK]
sophos/nginx-vts-exporter         Simple server that scrapes Nginx vts stats a…   7                    [OK]
ansibleplaybookbundle/nginx-apb   An APB to deploy NGINX                          3                    [OK]
wodby/nginx                       Generic nginx                                   1                    [OK]
arnau/nginx-gate                  Docker image with Nginx with Lua enabled on …   1                    [OK]
centos/nginx-110-centos7          Platform for running nginx 1.10 or building …   0                    

• docker pull → 从registry中拉取一个镜像或仓库

[root@localhost ~]# docker pull nginx:1.20.2
1.20.2: Pulling from library/nginx
eff15d958d66: Pull complete 
1f3e1e3ef6aa: Pull complete 
231009cab23f: Pull complete 
b2ef879f0046: Pull complete 
5495a7eec709: Pull complete 
ddde57a4eac9: Pull complete 
Digest: sha256:6ce65dd1f3bf44fa60a0212f0f893b78a706f20f09c884b43de50037067d9f5d
Status: Downloaded newer image for nginx:1.20.2
docker.io/library/nginx:1.20.2

• docker images → 列出镜像的详细信息

[root@localhost ~]# docker images
REPOSITORY   TAG       IMAGE ID       CREATED       SIZE
nginx        1.20.2    aedf7f31bdab   2 weeks ago   141MB

• docker create → 创建新的容器

[root@localhost ~]# docker create nginx
Unable to find image 'nginx:latest' locally
latest: Pulling from library/nginx
eff15d958d66: Already exists 
1e5351450a59: Pull complete 
2df63e6ce2be: Pull complete 
9171c7ae368c: Pull complete 
020f975acd28: Pull complete 
266f639b35ad: Pull complete 
Digest: sha256:097c3a0913d7e3a5b01b6c685a60c03632fc7a2b50bc8e35bcaa3691d788226e
Status: Downloaded newer image for nginx:latest
a2ea3d233157813ee4e6cf4bfdf46aac33d3c8df01a3489607c7d2bc4e52da89

[root@localhost ~]# docker create busybox sleep 3600
Unable to find image 'busybox:latest' locally
latest: Pulling from library/busybox
3aab638df1a9: Pull complete 
Digest: sha256:52817dece4cfe26f581c834d27a8e1bcc82194f914afe6d50afad5a101234ef1
Status: Downloaded newer image for busybox:latest
3f3353ebf447da22ea1248e18067e45357d2688e34f411653919e706df116e8d
[root@localhost ~]# docker ps -a
CONTAINER ID   IMAGE     COMMAND                  CREATED              STATUS                       PORTS     NAMES
3f3353ebf447   busybox   "sleep 3600"             About a minute ago   Created                                beautiful_driscoll
66565bdd7b1f   nginx     "/docker-entrypoint.…"   14 minutes ago       Exited (137) 6 minutes ago             stoic_curie
[root@localhost ~]# docker start 3f3353ebf447
3f3353ebf447
[root@localhost ~]# docker ps
CONTAINER ID   IMAGE     COMMAND        CREATED         STATUS          PORTS     NAMES
3f3353ebf447   busybox   "sleep 3600"   2 minutes ago   Up 55 seconds             beautiful_driscoll

• docker ps → 列出容器

[root@localhost ~]# docker ps -a    // -a 查看所有容器
CONTAINER ID   IMAGE     COMMAND                  CREATED              STATUS    PORTS     NAMES
66565bdd7b1f   nginx     "/docker-entrypoint.…"   About a minute ago   Created             stoic_curie
a2ea3d233157   nginx     "/docker-entrypoint.…"   About a minute ago   Created             sad_fermi

• docker start → 启动容器

[root@localhost ~]# docker start 66565bdd7b1f
66565bdd7b1f
[root@localhost ~]# docker ps
CONTAINER ID   IMAGE     COMMAND                  CREATED         STATUS         PORTS     NAMES
66565bdd7b1f   nginx     "/docker-entrypoint.…"   3 minutes ago   Up 4 seconds   80/tcp    stoic_curie

• docker restart → 重新启动容器

[root@localhost ~]# docker restart 66565bdd7b1f
66565bdd7b1f
[root@localhost ~]# docker ps
CONTAINER ID   IMAGE     COMMAND                  CREATED         STATUS         PORTS     NAMES
66565bdd7b1f   nginx     "/docker-entrypoint.…"   5 minutes ago   Up 6 seconds   80/tcp    stoic_curie

• docker stop → 停止正在运行的容器

[root@localhost ~]# docker stop 66565bdd7b1f
66565bdd7b1f
[root@localhost ~]# docker ps
CONTAINER ID   IMAGE     COMMAND   CREATED   STATUS    PORTS     NAMES
[root@localhost ~]# docker ps -a
CONTAINER ID   IMAGE     COMMAND                  CREATED         STATUS                      PORTS     NAMES
66565bdd7b1f   nginx     "/docker-entrypoint.…"   6 minutes ago   Exited (0) 17 seconds ago             stoic_curie

• docker kill → 杀死正在运行的容器

[root@localhost ~]# docker kill 66565bdd7b1f
66565bdd7b1f
[root@localhost ~]# docker ps -a
CONTAINER ID   IMAGE     COMMAND                  CREATED         STATUS                       PORTS     NAMES
66565bdd7b1f   nginx     "/docker-entrypoint.…"   8 minutes ago   Exited (137) 8 seconds ago             stoic_curie

• docker run → 在新容器中运行命令

[root@localhost ~]# docker run -it busybox /bin/sh     // -i 交互模式，可以使用-i进入容器； -t tty 给它一个站的住脚的位置
/ # ls
bin   dev   etc   home  proc  root  sys   tmp   usr   var
/ # pwd
/

[root@localhost ~]# docker run -d httpd    // 运行（部署）一个网站
Unable to find image 'httpd:latest' locally
latest: Pulling from library/httpd
eff15d958d66: Already exists 
ba1caf8ba86c: Pull complete 
ab86dc02235d: Pull complete 
0d58b11d2867: Pull complete 
e88da7cb925c: Pull complete 
Digest: sha256:1d71eef54c08435c0be99877c408637f03112dc9f929fba3cccdd15896099b02
Status: Downloaded newer image for httpd:latest
2dd4b4019147f7409a5bb78869a508149c15e6449412323076564df76f1d12d0
[root@localhost ~]# docker ps
CONTAINER ID   IMAGE     COMMAND              CREATED          STATUS         PORTS     NAMES
2dd4b4019147   httpd     "httpd-foreground"   9 seconds ago    Up 8 seconds   80/tcp    infallible_thompson
3f3353ebf447   busybox   "sleep 3600"         10 minutes ago   Up 9 minutes             beautiful_driscoll

• docker logs → 获取容器的日志

[root@localhost ~]# docker logs 2dd4b4019147
AH00558: httpd: Could not reliably determine the server's fully qualified domain name, using 172.17.0.4. Set the 'ServerName' directive globally to suppress this message
AH00558: httpd: Could not reliably determine the server's fully qualified domain name, using 172.17.0.4. Set the 'ServerName' directive globally to suppress this message
[Wed Dec 01 14:58:17.793554 2021] [mpm_event:notice] [pid 1:tid 139649966746944] AH00489: Apache/2.4.51 (Unix) configured -- resuming normal operations
[Wed Dec 01 14:58:17.793789 2021] [core:notice] [pid 1:tid 139649966746944] AH00094: Command line: 'httpd -D FOREGROUND'
172.17.0.1 - - [01/Dec/2021:15:01:33 +0000] "GET / HTTP/1.1" 200 45

• docker rm → 删除容器

[root@localhost ~]# docker ps
CONTAINER ID   IMAGE     COMMAND              CREATED          STATUS          PORTS     NAMES
2dd4b4019147   httpd     "httpd-foreground"   5 minutes ago    Up 5 minutes    80/tcp    infallible_thompson
3f3353ebf447   busybox   "sleep 3600"         16 minutes ago   Up 14 minutes             beautiful_driscoll
[root@localhost ~]# docker rm -f 3f3353ebf447
3f3353ebf447
[root@localhost ~]# docker ps
CONTAINER ID   IMAGE     COMMAND              CREATED         STATUS         PORTS     NAMES
2dd4b4019147   httpd     "httpd-foreground"   6 minutes ago   Up 6 minutes   80/tcp    infallible_thompson

[root@localhost ~]# docker ps -a
CONTAINER ID   IMAGE     COMMAND                  CREATED          STATUS                        PORTS     NAMES
2dd4b4019147   httpd     "httpd-foreground"       7 minutes ago    Up 7 minutes                  80/tcp    infallible_thompson
66565bdd7b1f   nginx     "/docker-entrypoint.…"   30 minutes ago   Exited (137) 22 minutes ago             stoic_curie
a2ea3d233157   nginx     "/docker-entrypoint.…"   30 minutes ago   Created                                 sad_fermi
[root@localhost ~]# docker ps -aq
2dd4b4019147
66565bdd7b1f
a2ea3d233157
[root@localhost ~]# docker rm $(docker ps -aq)
66565bdd7b1f
a2ea3d233157
Error response from daemon: You cannot remove a running container 2dd4b4019147f7409a5bb78869a508149c15e6449412323076564df76f1d12d0. Stop the container before attempting removal or force remove
[root@localhost ~]# docker ps -a
CONTAINER ID   IMAGE     COMMAND              CREATED         STATUS         PORTS     NAMES
2dd4b4019147   httpd     "httpd-foreground"   8 minutes ago   Up 8 minutes   80/tcp    infallible_thompson

• docker attach → 连接到正在运行的容器上（进到容器里面后不能做任何事，必须按ctrl+c才能退出，但是ctrl+c退出后，容器也退出了，所以这种方式平时不会用到）

[root@localhost ~]# docker attach 2dd4b4019147

ls
quit
^C[Wed Dec 01 15:09:01.018352 2021] [mpm_event:notice] [pid 1:tid 139649966746944] AH00491: caught SIGTERM, shutting down

• docker exec → 在正在运行的容器中运行命令（exec必须用交互模式进入容器，用exit退出后，容器依然会运行）

[root@localhost ~]# docker exec -it 2dd4b4019147 /bin/bash
root@2dd4b4019147:/usr/local/apache2# exit
exit

• docker info → 显示系统范围的信息

[root@localhost ~]# docker info
Client:
 Context:    default
 Debug Mode: false
 Plugins:
  app: Docker App (Docker Inc., v0.9.1-beta3)
  buildx: Build with BuildKit (Docker Inc., v0.6.3-docker)
  scan: Docker Scan (Docker Inc., v0.9.0)

Server:
 Containers: 0
  Running: 0
  Paused: 0
  Stopped: 0
 Images: 0
 Server Version: 20.10.11
 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: 7b11cfaabd73bb80907dd23182b9347b4245eb5d
 runc version: v1.0.2-0-g52b36a2
 init version: de40ad0
 Security Options:
  seccomp
   Profile: default
 Kernel Version: 3.10.0-862.el7.x86_64
 Operating System: CentOS Linux 7 (Core)
 OSType: linux
 Architecture: x86_64
 CPUs: 2
 Total Memory: 1.779GiB
 Name: localhost.localdomain
 ID: BYNG:CDGP:V62W:5NS4:CQPZ:ZCHU:N2YY:DMF6:CDVT:WMOJ:ZQW4:D7IP
 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
 Live Restore Enabled: false

• docker inspect → 返回有关Docker对象的详细信息

[root@localhost ~]# docker inspect 2dd4b4019147
[
    {
        "Id": "2dd4b4019147f7409a5bb78869a508149c15e6449412323076564df76f1d12d0",
        "Created": "2021-12-01T14:58:17.480606425Z",
        "Path": "httpd-foreground",
        "Args": [],
        "State": {
            "Status": "running",
            "Running": true,
            "Paused": false,
            "Restarting": false,
            "OOMKilled": false,
            "Dead": false,
            "Pid": 40723,
            "ExitCode": 0,
            "Error": "",
            "StartedAt": "2021-12-01T14:58:17.767659939Z",
            "FinishedAt": "0001-01-01T00:00:00Z"
        },
        "Image": "sha256:ad17c88403e2cedd27963b98be7f04bd3f903dfa7490586de397d0404424936d",
        "ResolvConfPath": "/var/lib/docker/containers/2dd4b4019147f7409a5bb78869a508149c15e6449412323076564df76f1d12d0/resolv.conf",
        "HostnamePath": "/var/lib/docker/containers/2dd4b4019147f7409a5bb78869a508149c15e6449412323076564df76f1d12d0/hostname",
        "HostsPath": "/var/lib/docker/containers/2dd4b4019147f7409a5bb78869a508149c15e6449412323076564df76f1d12d0/hosts",
        "LogPath": "/var/lib/docker/containers/2dd4b4019147f7409a5bb78869a508149c15e6449412323076564df76f1d12d0/2dd4b4019147f7409a5bb78869a508149c15e6449412323076564df76f1d12d0-json.log",
        "Name": "/infallible_thompson",
        "RestartCount": 0,
        "Driver": "overlay2",
        "Platform": "linux",
        "MountLabel": "",
        "ProcessLabel": "",
        "AppArmorProfile": "",
        "ExecIDs": null,
        "HostConfig": {
            "Binds": null,
            "ContainerIDFile": "",
            "LogConfig": {
                "Type": "json-file",
                "Config": {}
            },
            "NetworkMode": "default",
            "PortBindings": {},
            "RestartPolicy": {
                "Name": "no",
                "MaximumRetryCount": 0
            },
            "AutoRemove": false,
            "VolumeDriver": "",
            "VolumesFrom": null,
            "CapAdd": null,
            "CapDrop": null,
            "CgroupnsMode": "host",
            "Dns": [],
            "DnsOptions": [],
            "DnsSearch": [],
            "ExtraHosts": null,
            "GroupAdd": null,
            "IpcMode": "private",
            "Cgroup": "",
            "Links": null,
            "OomScoreAdj": 0,
            "PidMode": "",
            "Privileged": false,
            "PublishAllPorts": false,
            "ReadonlyRootfs": false,
            "SecurityOpt": null,
            "UTSMode": "",
            "UsernsMode": "",
            "ShmSize": 67108864,
            "Runtime": "runc",
            "ConsoleSize": [
                0,
                0
            ],
            "Isolation": "",
            "CpuShares": 0,
            "Memory": 0,
            "NanoCpus": 0,
            "CgroupParent": "",
            "BlkioWeight": 0,
            "BlkioWeightDevice": [],
            "BlkioDeviceReadBps": null,
            "BlkioDeviceWriteBps": null,
            "BlkioDeviceReadIOps": null,
            "BlkioDeviceWriteIOps": null,
            "CpuPeriod": 0,
            "CpuQuota": 0,
            "CpuRealtimePeriod": 0,
            "CpuRealtimeRuntime": 0,
            "CpusetCpus": "",
            "CpusetMems": "",
            "Devices": [],
            "DeviceCgroupRules": null,
            "DeviceRequests": null,
            "KernelMemory": 0,
            "KernelMemoryTCP": 0,
            "MemoryReservation": 0,
            "MemorySwap": 0,
            "MemorySwappiness": null,
            "OomKillDisable": false,
            "PidsLimit": null,
            "Ulimits": null,
            "CpuCount": 0,
            "CpuPercent": 0,
            "IOMaximumIOps": 0,
            "IOMaximumBandwidth": 0,
            "MaskedPaths": [
                "/proc/asound",
                "/proc/acpi",
                "/proc/kcore",
                "/proc/keys",
                "/proc/latency_stats",
                "/proc/timer_list",
                "/proc/timer_stats",
                "/proc/sched_debug",
                "/proc/scsi",
                "/sys/firmware"
            ],
            "ReadonlyPaths": [
                "/proc/bus",
                "/proc/fs",
                "/proc/irq",
                "/proc/sys",
                "/proc/sysrq-trigger"
            ]
        },
        "GraphDriver": {
            "Data": {
                "LowerDir": "/var/lib/docker/overlay2/59806da4fa41ad1fabf77b620307211cd490f177e1ce9e593084ca01a06a12c2-init/diff:/var/lib/docker/overlay2/36ed93e176c0efdde307d3bc1d79afde06b98ce5d55e8a5559f9d52898fa700f/diff:/var/lib/docker/overlay2/da05fe4a138adfa74195fbe6b7d48a1e33b7bdef9991dc56f0d41c9dce0dee6c/diff:/var/lib/docker/overlay2/9c7068052b46318736e32d7e970398f0fe7df8a749201bcf60c692f410cba13d/diff:/var/lib/docker/overlay2/1953bf937cd0997d8b717ca69f3c0384de3497ff7292af506c90eb4d371ad2d0/diff:/var/lib/docker/overlay2/c69f8634857d44cd89525b782bd5c39014984e753f7ebc5b6c3e661577c87b3b/diff",
                "MergedDir": "/var/lib/docker/overlay2/59806da4fa41ad1fabf77b620307211cd490f177e1ce9e593084ca01a06a12c2/merged",
                "UpperDir": "/var/lib/docker/overlay2/59806da4fa41ad1fabf77b620307211cd490f177e1ce9e593084ca01a06a12c2/diff",
                "WorkDir": "/var/lib/docker/overlay2/59806da4fa41ad1fabf77b620307211cd490f177e1ce9e593084ca01a06a12c2/work"
            },
            "Name": "overlay2"
        },
        "Mounts": [],
        "Config": {
            "Hostname": "2dd4b4019147",
            "Domainname": "",
            "User": "",
            "AttachStdin": false,
            "AttachStdout": false,
            "AttachStderr": false,
            "ExposedPorts": {
                "80/tcp": {}
            },
            "Tty": false,
            "OpenStdin": false,
            "StdinOnce": false,
            "Env": [
                "PATH=/usr/local/apache2/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin",
                "HTTPD_PREFIX=/usr/local/apache2",
                "HTTPD_VERSION=2.4.51",
                "HTTPD_SHA256=20e01d81fecf077690a4439e3969a9b22a09a8d43c525356e863407741b838f4",
                "HTTPD_PATCHES="
            ],
            "Cmd": [
                "httpd-foreground"
            ],
            "Image": "httpd",
            "Volumes": null,
            "WorkingDir": "/usr/local/apache2",
            "Entrypoint": null,
            "OnBuild": null,
            "Labels": {},
            "StopSignal": "SIGWINCH"
        },
        "NetworkSettings": {
            "Bridge": "",
            "SandboxID": "08e39e54dcab30e7d01e8dd0c9d69668a39e2afab86cd846fad09e217fbb8b50",
            "HairpinMode": false,
            "LinkLocalIPv6Address": "",
            "LinkLocalIPv6PrefixLen": 0,
            "Ports": {
                "80/tcp": null
            },
            "SandboxKey": "/var/run/docker/netns/08e39e54dcab",
            "SecondaryIPAddresses": null,
            "SecondaryIPv6Addresses": null,
            "EndpointID": "15b1dcd50fb8583744379ec7a65a6bbccf8e4fe76c81ef57ebdf36e817395f6f",
            "Gateway": "172.17.0.1",
            "GlobalIPv6Address": "",
            "GlobalIPv6PrefixLen": 0,
            "IPAddress": "172.17.0.4",
            "IPPrefixLen": 16,
            "IPv6Gateway": "",
            "MacAddress": "02:42:ac:11:00:04",
            "Networks": {
                "bridge": {
                    "IPAMConfig": null,
                    "Links": null,
                    "Aliases": null,
                    "NetworkID": "1e342ac6b2af20d51aa467e89ce0d41f754e4daca47beb34de0a6c0de81750d2",
                    "EndpointID": "15b1dcd50fb8583744379ec7a65a6bbccf8e4fe76c81ef57ebdf36e817395f6f",
                    "Gateway": "172.17.0.1",
                    "IPAddress": "172.17.0.4",
                    "IPPrefixLen": 16,
                    "IPv6Gateway": "",
                    "GlobalIPv6Address": "",
                    "GlobalIPv6PrefixLen": 0,
                    "MacAddress": "02:42:ac:11:00:04",
                    "DriverOpts": null
                }
            }
        }
    }
]
[root@localhost ~]# curl 172.17.0.4
<html><body><h1>It works!</h1></body></html>

八、docker事件状态