Docker(一) 入门

之前相应做过一些Docker的记录, 但不成系统. 最近看了billbill上狂神的docker视频, 结合视频的笔记和之前的记录, 争取把docker的知识体系完善起来

1. Docker概述

基本介绍

Docker是一个开源的应用容器引擎, 基于Go语言并遵从Apache 2.0协议开源. Docker可以让开发者打包他们的应用以及依赖包到一个轻量级, 可移植的容器中, 然后发布到任何流行的Linux机器上, 也可以实现虚拟化. 容器时完全使用沙箱机制, 相互之间不会有任何接口, 更重要的是容器性能开销极低

应用场景

Web应用的自动化打包和发布
自动化测试和持续集成, 发布
在服务型环境中部署和调整数据库或其他的后台应用
从头编译或者扩展现有的OpenShift或Cloud Foundry平台来搭建自己的PaaS(Platform-as-a-Service)环境

优势

快速，一致地交付您的应用程序。Docker 允许开发人员使用您提供的应用程序或服务的本地容器在标准化环境中工作，从而简化了开发的生命周期
响应式部署和扩展
在同一硬件上运行更多工作负载

2. 虚拟化技术和容器化技术

虚拟化技术特点：1.资源占用多 2.冗余步骤多 3.启动很慢

容器化技术：容器化技术不是模拟的一个完整的操作系统

Docker和虚拟机的不同:

传统虚拟机，虚拟出硬件，运行一个完整的操作系统，然后在这个系统上安装和运行软件
Docker容器内的应用直接运行在宿主机的内容，容器是没有自己的内核的，也没有虚拟硬件
每个容器都是相互隔离的，每个容器都有属于自己的文件系统，互不影响

3. Docker的系统架构

Docker使用客户端/服务器(C/S)架构模式, 使用远程API来管理和创建Docker容器, Docker容器通过Docker镜像来创建, 容器与镜像的关系类似于面向对象编程中对象与类

标题	说明
镜像(Images)	Docker镜像是用于创建Docker容器的模板
容器	容器时独立运行的一个或一组应用
客户端	Docker客户端通过命令行或者其他工具使用Docker API
主机	一个物理或者虚拟的机器用于执行Docker守护进程和容器
仓库	Docker仓库用来保存镜像, 可以理解为代码控制中的代码仓库
Docker Machine	Docker Machine是一个Docker安装的命令行工具, 通过一个简单的命令即可以在相应的平台上安装Docker.

4. 安装

前提条件

Docker需要两个重要的安装要求

它仅适用于64位Linux安装

uname --m

它需要Linux内核版本3.10或更高版本

uname -r

安装

Ubuntu

使用在线安装脚本

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

执行后会自动下载并安装Docker及安装包

这个安装脚本会经常更新, 这个脚本安装的Docker是最新版的, 乌班图可以使用apt-install来安装Docker, 但是安装的版本可能比较旧, 如果想安装最新版的, 就需要使用这个版本进行安装

通过apt install进行安装

有时候安装慢, 还是可以通过apt install docker.io进行安装的

Centos

卸载旧的版本

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

下载需要的安装包

yum install -y yum-utils

设置镜像的仓库

yum-config-manager \--add-repo \https://download.docker.com/linux/centos/docker-ce.repo  #国外的地址# 设置阿里云的Docker镜像仓库
yum-config-manager \--add-repo \https://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo  #国外的地址

更新yum软件包索引

yum makecache fast

安装docker相关的配置

yum install docker-ce docker-ce-cli containerd.io

启动Docker

systemctl start docker
# 查看当前版本号，是否启动成功
docker version
# 设置开机自启动
systemctl enable docker

结果

下载hello-world镜像进行测试

查看下载的hello world镜像

[root@iZwz99sm8v95sckz8bd2c4Z lib]# docker images
REPOSITORY    TAG       IMAGE ID       CREATED         SIZE
hello-world   latest    bf756fb1ae65   11 months ago   13.3kB

5. Docker的卸载

# 1. 卸载依赖
yum remove docker-ce docker-ce-cli containerd.io
# 2. 删除资源  . /var/lib/docker是docker的默认工作路径
rm -rf /var/lib/docker

6. 配置阿里云镜像加速

进入阿里云官网，搜索容器镜像服务

依次执行官方的这四条命令

sudo mkdir -p /etc/docker
sudo tee /etc/docker/daemon.json <<-'EOF'
{"registry-mirrors": ["https://axvfsf7e.mirror.aliyuncs.com"]
}
EOF
sudo systemctl daemon-reload
sudo systemctl restart docker

7. 底层原理

Docker是一个Client-Server结构的系统，Docker的守护进程运行在主机上，通过Socker从客户端访问！Docker Server接收到Docker-Client的指令，就会执行这个指令！

Docker为什么比VM Ware快？

Docker比虚拟机更少的抽象层
Docker利用宿主机的内核，VM需要的是Guest OS

Docker新建一个容器的时候，不需要像虚拟机一样重新加载一个操作系统内核，直接利用宿主机的操作系统，而虚拟机是需要加载Guest OS。Docker和VM的对比如下:

8. 常用命令

8.1 基础命令

docker version          #查看docker的版本信息
docker info             #查看docker的系统信息,包括镜像和容器的数量
docker 命令 --help       #帮助命令(可查看可选的参数)
docker COMMAND --help

命令的帮助文档地址:https://docs.docker.com/engine/reference/commandline/docker/

8.2 镜像命令

查看本地主机的所有镜像

[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker images
REPOSITORY    TAG       IMAGE ID       CREATED         SIZE
hello-world   latest    bf756fb1ae65   11 months ago   13.3kB#解释:
1.REPOSITORY  镜像的仓库源2.TAG  镜像的标签3.IMAGE ID 镜像的id4.CREATED 镜像的创建时间5.SIZE 镜像的大小# 可选参数-a/--all 列出所有镜像-q/--quiet 只显示镜像的id

搜索镜像

[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker search mysql
NAME                              DESCRIPTION                                     STARS     OFFICIAL   AUTOMATED
mysql                             MySQL is a widely used, open-source relation…   10308     [OK]
mariadb                           MariaDB is a community-developed fork of MyS…   3819      [OK]
mysql/mysql-server                Optimized MySQL Server Docker images. Create…   754                  [OK]
percona                           Percona Server is a fork of the MySQL relati…   517       [OK]
centos/mysql-57-centos7           MySQL 5.7 SQL database server                   86
mysql/mysql-cluster               Experimental MySQL Cluster Docker images. Cr…   79
centurylink/mysql                 Image containing mysql. Optimized to be link…   60                   [OK]#可选参数Search the Docker Hub for imagesOptions:-f, --filter filter   Filter output based on conditions provided--format string   Pretty-print search using a Go template--limit int       Max number of search results (default 25)--no-trunc        Don't truncate output#搜索收藏数大于3000的镜像
[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker search mysql --filter=STARS=3000
NAME      DESCRIPTION                                     STARS     OFFICIAL   AUTOMATED
mysql     MySQL is a widely used, open-source relation…   10308     [OK]
mariadb   MariaDB is a community-developed fordockerk of MyS…   3819      [OK]

下载镜像

[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker pull mysql
Using default tag: latest            #如果不写tag默认就是latest
latest: Pulling from library/mysql
6ec7b7d162b2: Pull complete          #分层下载,docker image的核心-联合文件系统
fedd960d3481: Pull complete
7ab947313861: Pull complete
64f92f19e638: Pull complete
3e80b17bff96: Pull complete
014e976799f9: Pull complete
59ae84fee1b3: Pull complete
ffe10de703ea: Pull complete
657af6d90c83: Pull complete
98bfb480322c: Pull complete
6aa3859c4789: Pull complete
1ed875d851ef: Pull complete
Digest: sha256:78800e6d3f1b230e35275145e657b82c3fb02a27b2d8e76aac2f5e90c1c30873 #签名
Status: Downloaded newer image for mysql:latest
docker.io/library/mysql:latest  #下载来源的真实地址  #docker pull mysql等价于docker pull docker.io/library/mysql:latest

指定版本下载

[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker pull mysql:5.7
5.7: Pulling from library/mysql
6ec7b7d162b2: Already exists
fedd960d3481: Already exists
7ab947313861: Already exists
64f92f19e638: Already exists
3e80b17bff96: Already exists
014e976799f9: Already exists
59ae84fee1b3: Already exists
7d1da2a18e2e: Pull complete
301a28b700b9: Pull complete
529dc8dbeaf3: Pull complete
bc9d021dc13f: Pull complete
Digest: sha256:c3a567d3e3ad8b05dfce401ed08f0f6bf3f3b64cc17694979d5f2e5d78e10173
Status: Downloaded newer image for mysql:5.7
docker.io/library/mysql:5.7

删除镜像

#1.删除指定的镜像id
[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker rmi -f  镜像id
#2.删除多个镜像id
[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker rmi -f  镜像id 镜像id 镜像id
#3.删除全部的镜像id
[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker rmi -f  $(docker images -aq)

8.3 容器命令

运行容器

docker run [可选参数] image#参数说明
--name="名字"           指定容器名字
-d                     后台方式运行
-it                    使用交互方式运行,进入容器查看内容
-p                     指定容器的端口
(
-p ip:主机端口:容器端口  配置主机端口映射到容器端口
-p 主机端口:容器端口
-p 容器端口
)
-P                     随机指定端口(大写的P)

进入容器

[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker run -it centos /bin/bash
[root@bd1b8900c547 /]# ls
bin  dev  etc  home  lib  lib64  lost+found  media  mnt  opt  proc  root  run  sbin  srv  sys  tmp  usr  var

退出容器

#exit 停止并退出容器（后台方式运行则仅退出）
#Ctrl+P+Q  不停止容器退出
[root@bd1b8900c547 /]# exit
exit
[root@iZwz99sm8v95sckz8bd2c4Z ~]#

列出运行过的容器

#docker ps # 列出当前正在运行的容器
-a   # 列出所有容器的运行记录
-n=? # 显示最近创建的n个容器
-q   # 只显示容器的编号[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker ps
CONTAINER ID   IMAGE     COMMAND   CREATED   STATUS    PORTS     NAMES
[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker ps -a
CONTAINER ID   IMAGE          COMMAND       CREATED         STATUS                     PORTS     NAMES
bca129320bb5   centos         "/bin/bash"   4 minutes ago   Exited (0) 3 minutes ago             optimistic_shtern
bd1b8900c547   centos         "/bin/bash"   6 minutes ago   Exited (0) 5 minutes ago             cool_tesla
cf6adbf1b506   bf756fb1ae65   "/hello"      5 hours ago     Exited (0) 5 hours ago               optimistic_darwin

删除容器

docker rm 容器id                 #删除指定的容器,不能删除正在运行的容器,强制删除使用 rm -f
docker rm -f $(docker ps -aq)   #删除所有的容器
docker ps -a -q|xargs docker rm #删除所有的容器

启动和停止容器

docker start 容器id          #启动容器
docker restart 容器id        #重启容器
docker stop 容器id           #停止当前运行的容器
docker kill 容器id           #强制停止当前容器

8.4 其他常用命令

日志的查看

[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker logs --helpUsage:  docker logs [OPTIONS] CONTAINERFetch the logs of a containerOptions:--details        Show extra details provided to logs-f, --follow         Follow log output--since string   Show logs since timestamp (e.g. 2013-01-02T13:23:37Z) or relative (e.g. 42m for 42 minutes)-n, --tail string    Number of lines to show from the end of the logs (default "all")-t, --timestamps     Show timestamps--until string   Show logs before a timestamp (e.g. 2013-01-02T13:23:37Z) or relative (e.g. 42m for 42 minutes)常用：
docker logs -tf 容器id
docker logs --tail number 容器id #num为要显示的日志条数#docker容器后台运行，必须要有一个前台的进程，否则会自动停止
#编写shell脚本循环执行，使得centos容器保持运行状态
[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker run -d centos /bin/sh -c "while true;do echo hi;sleep 5;done"
c703b5b1911ff84d584390263a35707b6024816e1f46542b61918a6327a570dc
[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker ps
CONTAINER ID   IMAGE     COMMAND                  CREATED          STATUS          PORTS     NAMES
c703b5b1911f   centos    "/bin/sh -c 'while t…"   13 seconds ago   Up 10 seconds             pedantic_banach
[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker logs -tf --tail 10 c703b5b1911f
2020-12-27T03:34:07.255599560Z hi
2020-12-27T03:34:12.257641517Z hi
2020-12-27T03:34:17.259706294Z hi
2020-12-27T03:34:22.261693707Z hi
2020-12-27T03:34:27.262609289Z hi
2020-12-27T03:34:32.267862677Z hi
2020-12-27T03:34:37.270382873Z hi
2020-12-27T03:34:42.272414182Z hi
2020-12-27T03:34:47.274823243Z hi
2020-12-27T03:34:52.277419274Z hi

查看容器中进程信息

[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker top c703b5b1911f
UID                 PID                 PPID                C                   STIME               TTY                 TIME                CMD
root                11156               11135               0                   11:31               ?                   00:00:00            /bin/sh -c while true;do echo hi;sleep 5;done
root                11886               11156               0                   11:43               ?                   00:00:00            /usr/bin/coreutils --coreutils-prog-shebang=sleep /usr/bin/sleep 5

查看容器的元数据

[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker inspect 容器id

进入当前正在运行的容器

通常我们的容器都是使用后台方式来运行的，有时需要进入容器修改配置

方式一:

[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker exec -it c703b5b1911f /bin/bash
[root@c703b5b1911f /]# ls
bin  dev  etc  home  lib  lib64  lost+found  media  mnt  opt  proc  root  run  sbin  srv  sys  tmp  usr  var
[root@c703b5b1911f /]# ps -ef
UID        PID  PPID  C STIME TTY          TIME CMD
root         1     0  0 03:31 ?        00:00:00 /bin/sh -c while true;do echo hi;sleep 5;done
root       279     0  0 03:54 pts/0    00:00:00 /bin/bash
root       315     1  0 03:56 ?        00:00:00 /usr/bin/coreutils --coreutils-prog-shebang=sleep /usr/bin/sleep 5
root       316   279  0 03:56 pts/0    00:00:00 ps -ef

方式二:

[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker attach c703b5b1911f

docker exec 进入容器后开启一个新的终端，可以在里面操作

docker attach 进入容器正在执行的终端，不会启动新的进程

拷贝操作

#拷贝容器的文件到主机中
docker cp 容器id:容器内路径  目的主机路径#拷贝宿主机的文件到容器中
docker cp 目的主机路径 容器id:容器内路径

[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker exec -it c703b5b1911f /bin/bash
[root@c703b5b1911f /]# cd home
[root@c703b5b1911f home]# ls
#touch 新建文件
[root@c703b5b1911f home]# touch test.java
[root@c703b5b1911f home]# ls
test.java
[root@c703b5b1911f home]# exit
exit
[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker ps
CONTAINER ID   IMAGE     COMMAND                  CREATED          STATUS          PORTS     NAMES
c703b5b1911f   centos    "/bin/sh -c 'while t…"   35 minutes ago   Up 35 minutes             pedantic_banach
[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker cp c703b5b1911f:/home/test.java /home
[root@iZwz99sm8v95sckz8bd2c4Z ~]# ls /home
hai  pan  test.java

命令小节的图解如下:

9. 图形化管理工具Portaniner安装

Portaniner是Docker的图形化管理工具，类似的工具还有Rancher(CI/CD再用)

下载运行Portaniner镜像并运行，设置本机映射端口为8088

[root@localhost conf]# docker run -d -p 8088:9000 --restart=always -v /var/run/docker.sock:/var/run/docker.sock --privileged=true portainer/portainer
Unable to find image 'portainer/portainer:latest' locally
latest: Pulling from portainer/portainer
94cfa856b2b1: Pull complete
49d59ee0881a: Pull complete
a2300fd28637: Pull complete
Digest: sha256:fb45b43738646048a0a0cc74fcee2865b69efde857e710126084ee5de9be0f3f
Status: Downloaded newer image for portainer/portainer:latest
8c525a0137be22965bd1e3944da622a2c4248f8ad20883f4b3ea4f8a6b11e163
[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker ps
CONTAINER ID   IMAGE                 COMMAND        CREATED         STATUS         PORTS                    NAMES
7789d4505a00   portainer/portainer   "/portainer"   6 seconds ago   Up 5 seconds   0.0.0.0:8088->9000/tcp   quirky_sinoussi

第一次登录设置admin用户的密码

如果是阿里云服务器记得设置安全组，选择连接本地的Docker,整体界面预览如下图

10. Docker镜像详解

10.1 什么是镜像

镜像是一种轻量级、可执行的独立软件包，用来打包软件运行环境和基于运行环境开发的软件，它包含运行某个软件所需要的所有内容，包括代码，运行时（一个程序在运行或者在被执行的依赖）、库，环境变量和配置文件

10.2 Docker镜像加载原理

Docker的镜像实际上由一层一层的文件系统组成，这种层级的文件系统是UnionFS联合文件系统。

10.3 分层理解

[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker image inspect nginx:latest
[{"Id": "sha256:ae2feff98a0cc5095d97c6c283dcd33090770c76d63877caa99aefbbe4343bdd","RepoTags": ["nginx:latest"],"RepoDigests": ["nginx@sha256:4cf620a5c81390ee209398ecc18e5fb9dd0f5155cd82adcbae532fec94006fb9"],"Parent": "","Comment": "","Created": "2020-12-15T20:21:00.007674532Z","Container": "4cc5da85f27ca0d200407f0593422676a3bab482227daee044d797d1798c96c9","ContainerConfig": {"Hostname": "4cc5da85f27c","Domainname": "","User": "","AttachStdin": false,"AttachStdout": false,"AttachStderr": false,"ExposedPorts": {"80/tcp": {}},"Tty": false,"OpenStdin": false,"StdinOnce": false,"Env": ["PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin","NGINX_VERSION=1.19.6","NJS_VERSION=0.5.0","PKG_RELEASE=1~buster"],"Cmd": ["/bin/sh","-c","#(nop) ","CMD [\"nginx\" \"-g\" \"daemon off;\"]"],"Image": "sha256:13bffe371b56f4aeed88218ec17d0c6f653a83b49bd3e211fc8cfa2ca5d7a3d3","Volumes": null,"WorkingDir": "","Entrypoint": ["/docker-entrypoint.sh"],"OnBuild": null,"Labels": {"maintainer": "NGINX Docker Maintainers <docker-maint@nginx.com>"},"StopSignal": "SIGQUIT"},"DockerVersion": "19.03.12","Author": "","Config": {"Hostname": "","Domainname": "","User": "","AttachStdin": false,"AttachStdout": false,"AttachStderr": false,"ExposedPorts": {"80/tcp": {}},"Tty": false,"OpenStdin": false,"StdinOnce": false,"Env": ["PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin","NGINX_VERSION=1.19.6","NJS_VERSION=0.5.0","PKG_RELEASE=1~buster"],"Cmd": ["nginx","-g","daemon off;"],"Image": "sha256:13bffe371b56f4aeed88218ec17d0c6f653a83b49bd3e211fc8cfa2ca5d7a3d3","Volumes": null,"WorkingDir": "","Entrypoint": ["/docker-entrypoint.sh"],"OnBuild": null,"Labels": {"maintainer": "NGINX Docker Maintainers <docker-maint@nginx.com>"},"StopSignal": "SIGQUIT"},"Architecture": "amd64","Os": "linux","Size": 132935043,"VirtualSize": 132935043,"GraphDriver": {"Data": {"LowerDir": "/var/lib/docker/overlay2/cb791e78a08db7091bf2ce1d78603f1758f52199e57f1805156fe30e39067aae/diff:/var/lib/docker/overlay2/1e73a72b25af68ee9abf4eb443f778d31226e12e9af428fcc14c7b044c83b258/diff:/var/lib/docker/overlay2/88c9c01762f2af8327db65d0b0d4a64785e87c9c2ab76c62e7d03619db03a985/diff:/var/lib/docker/overlay2/7304ab112ac4a9cb91fc6f74730be28fecbe19f042e92d321aa9181424cc4b2e/diff","MergedDir": "/var/lib/docker/overlay2/48b288740bbb2b07b41ed43a4d17a005c46b08d3357d2960b5ef7db4b2de6618/merged","UpperDir": "/var/lib/docker/overlay2/48b288740bbb2b07b41ed43a4d17a005c46b08d3357d2960b5ef7db4b2de6618/diff","WorkDir": "/var/lib/docker/overlay2/48b288740bbb2b07b41ed43a4d17a005c46b08d3357d2960b5ef7db4b2de6618/work"},"Name": "overlay2"},"RootFS": {"Type": "layers","Layers": ["sha256:87c8a1d8f54f3aa4e05569e8919397b65056aa71cdf48b7f061432c98475eee9","sha256:5c4e5adc71a82a96f02632433de31c998c5a9e2fccdcbaee780ae83158fac4fa","sha256:7d2b207c26790f693ab1942bbe26af8e2b6a14248969e542416155a912fec30d","sha256:2c7498eef94aef8c40d106f3e42f7da62b3eee8fd36012bf7379becc4cd639a2","sha256:4eaf0ea085df254fd5d2beba4e2c11db70a620dfa411a8ad44149e26428caee4"]},"Metadata": {"LastTagTime": "0001-01-01T00:00:00Z"}}
]

这里指示了分层信息:

        "RootFS": {"Type": "layers","Layers": ["sha256:87c8a1d8f54f3aa4e05569e8919397b65056aa71cdf48b7f061432c98475eee9","sha256:5c4e5adc71a82a96f02632433de31c998c5a9e2fccdcbaee780ae83158fac4fa","sha256:7d2b207c26790f693ab1942bbe26af8e2b6a14248969e542416155a912fec30d","sha256:2c7498eef94aef8c40d106f3e42f7da62b3eee8fd36012bf7379becc4cd639a2","sha256:4eaf0ea085df254fd5d2beba4e2c11db70a620dfa411a8ad44149e26428caee4"]},

12.4 提交镜像

使用docker commit 命令提交容器成为一个新的版本docker commit -m=“提交的描述信息”  -a="作者" 容器id 目标镜像名:[TAG]

由于默认的Tomcat镜像的webapps文件夹中没有任何内容，需要从webapps.dist中拷贝文件到webapps文件夹。下面自行制作镜像：就是从webapps.dist中拷贝文件到webapps文件夹下，并提交该镜像作为一个新的镜像。使得该镜像默认的webapps文件夹下就有文件。具体命令如下：

#1.复制文件夹
[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker run -it tomcat /bin/bash
root@2a3bf3eaa2e4:/usr/local/tomcat# cd webapps
root@2a3bf3eaa2e4:/usr/local/tomcat/webapps# ls
root@2a3bf3eaa2e4:/usr/local/tomcat/webapps# cd ../
root@2a3bf3eaa2e4:/usr/local/tomcat# cp -r webapps.dist/* webapps
root@2a3bf3eaa2e4:/usr/local/tomcat# cd webapps
root@2a3bf3eaa2e4:/usr/local/tomcat/webapps# ls
ROOT  docs  examples  host-manager  manager
[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker ps
CONTAINER ID   IMAGE                 COMMAND        CREATED         STATUS         PORTS                    NAMES
2a3bf3eaa2e4   tomcat                "/bin/bash"    4 minutes ago   Up 4 minutes   8080/tcp                 competent_torvalds
7789d4505a00   portainer/portainer   "/portainer"   24 hours ago    Up 24 hours    0.0.0.0:8088->9000/tcp   quirky_sinoussi
[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker exec -it 2a3bf3eaa2e4 /bin/bash
root@2a3bf3eaa2e4:/usr/local/tomcat# cd webapps
root@2a3bf3eaa2e4:/usr/local/tomcat/webapps# ls
ROOT  docs  examples  host-manager  manager
root@2a3bf3eaa2e4:/usr/local/tomcat/webapps# cd ../
root@2a3bf3eaa2e4:/usr/local/tomcat# read escape sequence
[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker ps
CONTAINER ID   IMAGE                 COMMAND        CREATED         STATUS         PORTS                    NAMES
2a3bf3eaa2e4   tomcat                "/bin/bash"    8 minutes ago   Up 8 minutes   8080/tcp                 competent_torvalds
7789d4505a00   portainer/portainer   "/portainer"   24 hours ago    Up 24 hours    0.0.0.0:8088->9000/tcp   quirky_sinoussi
#2.提交镜像作为一个新的镜像[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker commit -m="add webapps" -a="Ethan" 2a3bf3eaa2e4 mytomcat:1.0
sha256:f189aac861de51087af5bc88a5f1de02d9574e7ee2d163c647dd7503a2d3982b
[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker images
REPOSITORY            TAG       IMAGE ID       CREATED         SIZE
mytomcat              1.0       f189aac861de   7 seconds ago   653MB
mysql                 5.7       f07dfa83b528   6 days ago      448MB
tomcat                latest    feba8d001e3f   10 days ago     649MB
nginx                 latest    ae2feff98a0c   12 days ago     133MB
centos                latest    300e315adb2f   2 weeks ago     209MB
portainer/portainer   latest    62771b0b9b09   5 months ago    79.1MB
elasticsearch         7.6.2     f29a1ee41030   9 months ago    791MB#3.运行容器[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker run -it mytomcat:1.0 /bin/bash
root@1645774d4605:/usr/local/tomcat# cd webapps
root@1645774d4605:/usr/local/tomcat/webapps# ls
ROOT  docs  examples  host-manager  manager
wz99sm8v95sckz8bd2c4Z ~]# docker images
REPOSITORY            TAG       IMAGE ID       CREATED         SIZE
mytomcat              1.0       f189aac861de   7 seconds ago   653MB
mysql                 5.7       f07dfa83b528   6 days ago      448MB
tomcat                latest    feba8d001e3f   10 days ago     649MB
nginx                 latest    ae2feff98a0c   12 days ago     133MB
centos                latest    300e315adb2f   2 weeks ago     209MB
portainer/portainer   latest    62771b0b9b09   5 months ago    79.1MB
elasticsearch         7.6.2     f29a1ee41030   9 months ago    791MB

11 常用容器部署

11.1 Nginx部署

搜索并下载镜像

[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker search nginx
NAME                               DESCRIPTION                                     STARS     OFFICIAL   AUTOMATED
nginx                              Official build of Nginx.                        14207     [OK]
jwilder/nginx-proxy                Automated Nginx reverse proxy for docker con…   1932                 [OK]
richarvey/nginx-php-fpm            Container running Nginx + PHP-FPM capable of…   797                  [OK]
linuxserver/nginx                  An Nginx container, brought to you by LinuxS…   137
jc21/nginx-proxy-manager           Docker container for managing Nginx proxy ho…   123
tiangolo/nginx-rtmp                Docker image with Nginx using the nginx-rtmp…   107                  [OK]
[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker pull nginx
Using default tag: latest
latest: Pulling from library/nginx
6ec7b7d162b2: Already exists
cb420a90068e: Pull complete
2766c0bf2b07: Pull complete
e05167b6a99d: Pull complete
70ac9d795e79: Pull complete
Digest: sha256:4cf620a5c81390ee209398ecc18e5fb9dd0f5155cd82adcbae532fec94006fb9
Status: Downloaded newer image for nginx:latest
docker.io/library/nginx:latest
[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker images;
REPOSITORY   TAG       IMAGE ID       CREATED       SIZE
mysql        5.7       f07dfa83b528   5 days ago    448MB
nginx        latest    ae2feff98a0c   11 days ago   133MB
centos       latest    300e315adb2f   2 weeks ago   209MB

可以到dockerhub官网查看Nginx的详细版本信息：https://hub.docker.com/nginx

运行测试

docker run -d --name nginx01 -p 3334:80 nginx-d 后台运行
--name 给容器命名
-p 3334:80 将宿主机的端口3334映射到该容器的80端口

运行结果

[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker exec -it nginx01 /bin/bash
Error: No such container: nginx01
[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker run -d --name nginx01 -p 3334:80 nginx
20c896637ff5de8be835797109d62ee2465e28d9d716be5a8d550ef7d547fcf5
[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker ps
CONTAINER ID   IMAGE     COMMAND                  CREATED         STATUS         PORTS                  NAMES
20c896637ff5   nginx     "/docker-entrypoint.…"   7 seconds ago   Up 5 seconds   0.0.0.0:3334->80/tcp   nginx01

配置文件

进入容器，自定义配置文件

[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker exec -it nginx01 /bin/bash
root@20c896637ff5:/# whereis nginx
nginx: /usr/sbin/nginx /usr/lib/nginx /etc/nginx /usr/share/nginx
root@20c896637ff5:/# cd /etc/nginx
root@20c896637ff5:/etc/nginx# ls
conf.d  fastcgi_params  koi-utf  koi-win  mime.types  modules  nginx.conf  scgi_params  uwsgi_params  win-utf
root@20c896637ff5:/# cd /etc/nginx
root@20c896637ff5:/etc/nginx# ls
conf.d  fastcgi_params  koi-utf  koi-win  mime.types  modules  nginx.conf  scgi_params  uwsgi_params  win-utf

访问测试

本地主机访问测试，curl命令发起请求，如果使用阿里云服务器需要设置安全组

[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker ps
CONTAINER ID   IMAGE     COMMAND                  CREATED         STATUS         PORTS                  NAMES
20c896637ff5   nginx     "/docker-entrypoint.…"   7 minutes ago   Up 7 minutes   0.0.0.0:3334->80/tcp   nginx01
[root@iZwz99sm8v95sckz8bd2c4Z ~]# curl localhost:3334
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>body {width: 35em;margin: 0 auto;font-family: Tahoma, Verdana, Arial, sans-serif;}
</style>
</head>
<body>
<h1>Welcome to nginx!</h1>
<p>If you see this page, the nginx web server is successfully installed and
working. Further configuration is required.</p><p>For online documentation and support please refer to
<a href="http://nginx.org/">nginx.org</a>.<br/>
Commercial support is available at
<a href="http://nginx.com/">nginx.com</a>.</p><p><em>Thank you for using nginx.</em></p>
</body>
</html>

安装vim

我们使用Nginx往往需要编写配置文件，但是Nginx官方镜像没有安装vim，需要我们手动进行安装。使用以下命令进行安装：

apt-get install vim

如果执行上述命令出现提示：

        Reading package lists... DoneBuilding dependency tree       Reading state information... DoneE: Unable to locate package vim

则需要先同步 /etc/apt/sources.list 和 /etc/apt/sources.list.d 中列出的源的索引，这样才能获取到最新的软件包。执行以下命令来更新：

apt-get update

更新完毕再安装即可。我们修改了配置文件，只要重新启动容器docker restart 容器id，改动就可以生效了。

解决vim在终端不能复制的问题：在vim 中输入 :set mouse=r。

拓展：启动项目并设置数据卷，为避免nginx因为修改配置文件导致的错误而无法启动容器，我们可以通过cp命令覆盖配置文件，但是设置数据卷会更为方便。启动Nginx容器的同时设置数据卷的命令：

docker run
--name my_nginx
-d -p 80:80
-v /data/nginx/conf/nginx.conf:/etc/nginx/nginx.conf
-v /data/nginx/log:/var/log/nginx
-v /data/nginx/html:/usr/share/nginx/html
nginx

参数说明：

第一个-v：挂载nginx的主配置文件，以方便在宿主机上直接修改容器的配置文件
第二个-v：挂载容器内nginx的日志，容器运行起来之后，可以直接在宿主机的这个目录中查看nginx日志
第三个-v：挂载静态页面目录

11.2 Tomcat部署

下载并运行

[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker pull tomcat
Using default tag: latest
latest: Pulling from library/tomcat
6c33745f49b4: Pull complete
ef072fc32a84: Pull complete
c0afb8e68e0b: Pull complete
d599c07d28e6: Pull complete
e8a829023b97: Pull complete
d04be46a31d1: Pull complete
db6007c69c35: Pull complete
e4ad4c894bce: Pull complete
248895fda357: Pull complete
277059b4cba2: Pull complete
Digest: sha256:57dae7dfb9b62a413cde65334c8a18893795cac70afc3be589c8336d8244655d
Status: Downloaded newer image for tomcat:latest
docker.io/library/tomcat:latest
[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker run -d -p 3335:8080 --name tomcat01 tomcat
7136295a6082cb0f805b025a1471bde02ead4864be3e2c9dcd337b1dde0a3113

进入容器

容器中的命令是少了, 阿里云镜像默认下载的是最小的镜像，保证最小的运行环境

[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker exec -it tomcat01 /bin/bash
root@7136295a6082:/usr/local/tomcat# ls
BUILDING.txt  CONTRIBUTING.md  LICENSE  NOTICE  README.md  RELEASE-NOTES  RUNNING.txt  bin  conf  lib  logs  native-jni-lib  temp  webapps  webapps.dist  work
root@7136295a6082:/usr/local/tomcat# cd webapps.dist
root@7136295a6082:/usr/local/tomcat/webapps.dist# ls
ROOT  docs  examples  host-manager  manager
root@7136295a6082:/usr/local/tomcat/webapps.dist# cd ROOT
root@7136295a6082:/usr/local/tomcat/webapps.dist/ROOT# ls
RELEASE-NOTES.txt  WEB-INF  asf-logo-wide.svg  bg-button.png  bg-middle.png  bg-nav.png  bg-upper.png  favicon.ico  index.jsp  tomcat.css  tomcat.svg
root@7136295a6082:/usr/local/tomcat/webapps.dist/ROOT# cd ../../
root@7136295a6082:/usr/local/tomcat# cd webapps
root@7136295a6082:/usr/local/tomcat/webapps# ls
root@7136295a6082:/usr/local/tomcat/webapps# cp -r /usr/local/tomcat/webapps.dist/* /usr/local/tomcat/webapps/
root@7136295a6082:/usr/local/tomcat/webapps# ls
ROOT  docs  examples  host-manager  manager
root@7136295a6082:/usr/local/tomcat/webapps# exit
exit

访问测试

[root@iZwz99sm8v95sckz8bd2c4Z ~]# curl localhost:3335<!DOCTYPE html>
<html lang="en"><head><meta charset="UTF-8" /><title>Apache Tomcat/9.0.41</title><link href="favicon.ico" rel="icon" type="image/x-icon" /><link href="tomcat.css" rel="stylesheet" type="text/css" /></head><body><div id="wrapper"><div id="navigation" class="curved container"><span id="nav-home"><a href="https://tomcat.apache.org/">Home</a></span><span id="nav-hosts"><a href="/docs/">Documentation</a></span><span id="nav-config"><a href="/docs/config/">Configuration</a></span><span id="nav-examples"><a href="/examples/">Examples</a></span><span id="nav-wiki"><a href="https://wiki.apache.org/tomcat/FrontPage">Wiki</a></span><span id="nav-lists"><a href="https://tomcat.apache.org/lists.html">Mailing Lists</a></span><span id="nav-help"><a href="https://tomcat.apache.org/findhelp.html">Find Help</a></span><br class="separator" /></div>

11.3 ElasticSearch部署

添加 ’-e ES_JAVA_OPTS="-Xms128m -Xmx512m" ‘ 配置ElasticSearch的虚拟机占用的内存大小

docker stats 查看资源占用情况

$ docker run -d --name elasticsearch -p 9200:9200 -p 9300:9300 -e "discovery.type=single-node" -e ES_JAVA_OPTS="-Xms128m -Xmx512m" elasticsearch:7.6.2[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker run -d --name elasticsearch01 -p 9200:9200 -p 9300:9300 -e "discovery.type=single-node" -e ES_JAVA_OPTS="-Xms128m -Xmx512m" elasticsearch:7.6.2
3b8cd4991814896c523ee67b84ce198e32bd82b1a62d512b198138a58ca946f1
[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker ps
CONTAINER ID   IMAGE                 COMMAND                  CREATED          STATUS         PORTS                                            NAMES
3b8cd4991814   elasticsearch:7.6.2   "/usr/local/bin/dock…"   10 seconds ago   Up 6 seconds   0.0.0.0:9200->9200/tcp, 0.0.0.0:9300->9300/tcp   elasticsearch01
[root@iZwz99sm8v95sckz8bd2c4Z ~]# docker stats

11.4 MySQL部署

下载并运行

#拉取并运行容器
docker run -d --name mysql-5.7 -p 3306:3306 -e MYSQL_ROOT_PASSWORD=123456 mysql:5.7

参数说明：

-p 3306:3306 ：映射容器服务的 3306 端口到宿主机的 3306 端口，外部主机可以直接通过 宿主机ip:3306 访问到 MySQL 的服务。
MYSQL_ROOT_PASSWORD=123456：设置 MySQL 服务 默认账号root 用户的密码。

进入容器查看MySQL服务

进入容器，并通过账号root查看MySQL服务能否正常连接

docker exec -it 9b3aad6819ff /bin/bash
mysql -h localhost -u root -p