1、Docker 简介
Docker是一个开源的容器引擎，它可以帮助我们更快地交付应用。Docker可将应用程序和基础设施层隔离，并且能将基础设施当作程序一样进行管理。使用Docker，可更快地打包、测试以及部署应用程序，并可减少从编写到部署运行代码的周期。
Docker 官方网站
https://www.docker.com/
docker 三要素：
- Docker 镜像（Images）：Docker镜像是一个只读模板，它包含创建Docker容器的说明。它和系统安装光盘有点像——我们使用系统安装光盘安装系统，同理，我们使用Docker镜像运行Docker镜像中的程序。
- 容器（Container）：容器是镜像的可运行实例。镜像和容器的关系有点类似于面向对象中，类和对象的关系。我们可通过Docker API或者CLI命令来启停、移动、删除容器。
- 仓库（Registry）：Docker Registry是一个集中存储与分发镜像的服务。我们构建完Docker镜像后，就可在当前宿主机上运行。但如果想要在其他机器上运行这个镜像，我们就需要手动拷贝。此时，我们可借助Docker Registry来避免镜像的手动拷贝。
一个Docker Registry可包含多个Docker仓库；每个仓库可包含多个镜像标签；每个标签对应一个Docker镜像。这跟Maven的仓库有点类似，如果把Docker Registry比作Maven仓库的话，那么Docker仓库就可理解为某jar包的路径，而镜像标签则可理解为jar包的版本号。
2、Docker 安装与启动
环境：Linux 操作系统，版本是CentOS7 64位 Docker是CE版本（免费版）
Docker 下载链接：链接失效请私信
链接：https://pan.baidu.com/s/1VTxUIz9XDcn3dD6spZEL1A?pwd=qns1
提取码：qns1
将该 rpm 利用 Xftp 上传至 Linux
切换 root 用户获取权限，然后进行安装即可。
su rootyum install -y docker-ce-18.06.0.ce-3.el7.x86_64.rpm安装完成，最后会出现 Complete !
3、启动与停止 Docker
systemctl start dockersystemctl status dockersystemctl stop dockersystemctl restart docker查询是否安装成功：会出现Docker相关的详情信息。安装完毕
docker info
[root@localhost file]# docker info
Containers: 6
Running: 2
Paused: 0
Stopped: 4
Images: 2
Server Version: 18.06.0-ce
Storage Driver: overlay2
Backing Filesystem: xfs
Supports d_type: true
Native Overlay Diff: true
Logging Driver: json-file
Cgroup Driver: cgroupfs
Plugins:
Volume: local
Network: bridge host macvlan null overlay
Log: awslogs fluentd gcplogs gelf journald json-file logentries splunk syslog
Swarm: inactive
Runtimes: runc
Default Runtime: runc
Init Binary: docker-init
containerd version: d64c661f1d51c48782c9cec8fda7604785f93587
runc version: 69663f0bd4b60df09991c08812a60108003fa340
init version: fec3683
Security Options:
seccomp
Profile: default
Kernel Version: 3.10.0-957.el7.x86_64
Operating System: CentOS Linux 7 (Core)
OSType: linux
Architecture: x86_64
CPUs: 1
Total Memory: 972.6MiB
Name: localhost.localdomain
ID: 33PU:JWNT:UBRS:CLMG:FEHQ:AGAL:APF6:3A3V:64SW:IEIM:XGAR:OOXP
Docker Root Dir: /var/lib/docker
Debug Mode (client): false
Debug Mode (server): false
Registry: https://index.docker.io/v1/
Labels:
Experimental: false
Insecure Registries:
127.0.0.0/8
Registry Mirrors:
https://4iydscvo.mirror.aliyuncs.com/
Live Restore Enabled: false
4、配置镜像加速器
阿里云镜像加速https://cr.console.aliyun.com/cn-hangzhou/instances/mirrors
sudo mkdir -p /etc/dockersudo tee /etc/docker/daemon.json <<-'EOF'
{
"registry-mirrors": ["https://4iydscvo.mirror.aliyuncs.com"]
}
EOFsudo systemctl daemon-reloadsudo systemctl restart docker最后docker info 查看是否配置成功，下图表示成功。
5、Docker 镜像操作常用指令
（1）搜索指令 docker search ...
docker search tomcat
（2）下载镜像 docker pull 镜像名称
docker pull tomcat
下载完成。
（3）查看本地镜像
docker images
（4）删除镜像，可以通过镜像IMAGE ID删除，也可以镜像名：版本号
docker rmi fb5657adc892
[root@localhost root123]# docker rmi c20987f18b13
Untagged: mysql:5.7
Untagged: mysql@sha256:f2ad209efe9c67104167fc609cca6973c8422939491c9345270175a300419f94
Deleted: sha256:c20987f18b130f9d144c9828df630417e2a9523148930dc3963e9d0dab302a76
Deleted: sha256:6567396b065ee734fb2dbb80c8923324a778426dfd01969f091f1ab2d52c7989
Deleted: sha256:0910f12649d514b471f1583a16f672ab67e3d29d9833a15dc2df50dd5536e40f
Deleted: sha256:6682af2fb40555c448b84711c7302d0f86fc716bbe9c7dc7dbd739ef9d757150
Deleted: sha256:5c062c3ac20f576d24454e74781511a5f96739f289edaadf2de934d06e910b92
Deleted: sha256:8805862fcb6ef9deb32d4218e9e6377f35fb351a8be7abafdf1da358b2b287ba
Deleted: sha256:872d2f24c4c64a6795e86958fde075a273c35c82815f0a5025cce41edfef50c7
Deleted: sha256:6fdb3143b79e1be7181d32748dd9d4a845056dfe16ee4c827410e0edef5ad3da
Deleted: sha256:b0527c827c82a8f8f37f706fcb86c420819bb7d707a8de7b664b9ca491c96838
Deleted: sha256:75147f61f29796d6528486d8b1f9fb5d122709ea35620f8ffcea0e0ad2ab0cd0
Deleted: sha256:2938c71ddf01643685879bf182b626f0a53b1356138ef73c40496182e84548aa
Deleted: sha256:ad6b69b549193f81b039a1d478bc896f6e460c77c1849a4374ab95f9a3d2cea2
（5）保存镜像为文件，首先下载一个java
docker pull javadocker save -o /home/file/jdk.tar java:latest
（6）将保存的镜像备份文件恢复镜像
先进行docker rmi 删除，在进行恢复。
docker rmi d23bdf5b1b1bdocker load -i/home/file/jdk.tar
查看镜像又恢复了。
docker images6、Docker 容器常用操作指令
先pull一个镜像
docker pull java:8（1）使用镜像创建一个容器
docker run java:8 /bin/echo 'caojun'
（2）列出容器
| docker ps | 列出当前正在运行的容器 |
| docker ps -a | 列出当前全部容器 |
| docker ps -a -q | 列出当前容器的所有编号 |
（3）停止容器
一下是两种停止容器的方法。
（4）启动容器 docker start 容器名称或容器编号
docker start 6cef8b21cada
（5）强制停止容器 docker kill 容器名称或容器编号
[root@localhost file]# docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
2954933039e6 mysql:5.7 "docker-entrypoint.s…" 11 minutes ago Up 11 minutes 33060/tcp, 0.0.0.0:33306->3306/tcp offcn_mysql
c2439c591c66 java:8 "/bin/bash" 21 minutes ago Up 21 minutes jdk1
[root@localhost file]# docker kill 2954933039e6
2954933039e6
[root@localhost file]# docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
c2439c591c66 java:8 "/bin/bash" 22 minutes ago Up 22 minutes jdk1
[root@localhost file]#
（6）重启容器 docker restart 容器名称或者容器编号
[root@localhost file]# docker restart 2954933039e6
2954933039e6
[root@localhost file]# docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
2954933039e6 mysql:5.7 "docker-entrypoint.s…" 13 minutes ago Up 6 seconds 33060/tcp, 0.0.0.0:33306->3306/tcp offcn_mysql
c2439c591c66 java:8 "/bin/bash" 23 minutes ago Up 23 minutes jdk1
[root@localhost file]#
（7）进入容器 docker exec -it heuristic_meninsky /bin/bash
[root@localhost file]# docker exec -it c2439c591c66 /bin/bash
root@c2439c591c66:/# java -version
openjdk version "1.8.0_111"
OpenJDK Runtime Environment (build 1.8.0_111-8u111-b14-2~bpo8+1-b14)
OpenJDK 64-Bit Server VM (build 25.111-b14, mixed mode)
root@c2439c591c66:/#
[root@localhost file]# docker exec -it 2954933039e6 /bin/bash
root@2954933039e6:/# mysql -uroot -p
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 2
Server version: 5.7.36 MySQL Community Server (GPL)
Copyright (c) 2000, 2021, Oracle and/or its affiliates.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
mysql>
（8）删除容器
docker rm 容器名称或者编号 //注意 不能删除正在运行中容器， 需要停掉才可以删除
docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
c2439c591c66 java:8 "/bin/bash" 37 minutes ago Up 37 minutes jdk1
[root@localhost root123]# docker rm c2439c591c66
Error response from daemon: You cannot remove a running container c2439c591c66982f5a55e97a7bc1cd67a5ffed5090e94eef41c59fb6833518e8. Stop the container before attempting removal or force remove
[root@localhost root123]# docker stop c2439c591c66
c2439c591c66
[root@localhost root123]# docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
[root@localhost root123]# docker rm c2439c591c66
c2439c591c66
[root@localhost root123]# docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
7、案例
（1）拉取java镜像
docker pull java:8创建容器
docker run -di --name jdk1 java:8进入容器
docker exec -it jdk1 /bin/bash
验证版本
java -version退出
exit[root@localhost file]# docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
java 8 d23bdf5b1b1b 6 years ago 643MB
[root@localhost file]# docker run -di --name jdk1 java:8
c2439c591c66982f5a55e97a7bc1cd67a5ffed5090e94eef41c59fb6833518e8
[root@localhost file]# docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
java 8 d23bdf5b1b1b 6 years ago 643MB
[root@localhost file]# docker exec -it jdk1 /bin/bash
root@c2439c591c66:/# java -version
openjdk version "1.8.0_111"
OpenJDK Runtime Environment (build 1.8.0_111-8u111-b14-2~bpo8+1-b14)
OpenJDK 64-Bit Server VM (build 25.111-b14, mixed mode)
root@c2439c591c66:/#
（2）拉取mysql镜像
docker pull mysql:5.7创建 mysql 容器（这里是最简单的方法进行创建）
docker run -d --name=offcn_mysql -p 33306:3306 -e MYSQL_ROOT_PASSWORD=123456 -e MYSQL_DATABASE=scwdb mysql:5.7 [root@localhost file]# docker run -d --name=offcn_mysql -p 33306:3306 -e MYSQL_ROOT_PASSWORD=123456 -e MYSQL_DATABASE=scwdb mysql:5.7
2954933039e63cbf0a00e2f808b5cf805565dbfa4c7e92c92180be76a995b8e6
[root@localhost file]# docker exec -it offcn_mysql /bin/bash
root@2954933039e6:/# mysql -u root -p
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 2
Server version: 5.7.36 MySQL Community Server (GPL)
Copyright (c) 2000, 2021, Oracle and/or its affiliates.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
mysql> ALTER USER 'root'@'%' IDENTIFIED WITH mysql_native_password BY '123456';
Query OK, 0 rows affected (0.00 sec)
mysql> flush privileges;
Query OK, 0 rows affected (0.00 sec)
mysql>
var code = "134c199f-0b00-47b4-b048-4e51ec776c0d"
