演示环境说明

1、《 Docker 镜像操作常用命令》中说明了如何从 Docker Hub 上下载镜像，《 Docker 容器操作常用命令》中说明了如何启动容器

2、本文将以完整的安装 MySQL 为例将镜像与容器操作完全串联起来

3、系统为 CentOS 7.5 发行版，内核为 3.10 版本，Docker 为 1.13 版本

[root@localhost ~]# lsb_release -a
LSB Version:	:core-4.1-amd64:core-4.1-noarch
Distributor ID:	CentOS
Description:	CentOS Linux release 7.5.1804 (Core) 
Release:	7.5.1804
Codename:	Core
[root@localhost ~]# uname -a
Linux localhost.localdomain 3.10.0-862.9.1.el7.x86_64 #1 SMP Mon Jul 16 16:29:36 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux
[root@localhost ~]# docker version
Client:Version:         1.13.1API version:     1.26Package version: docker-1.13.1-68.gitdded712.el7.centos.x86_64Go version:      go1.9.4Git commit:      dded712/1.13.1Built:           Tue Jul 17 18:34:48 2018OS/Arch:         linux/amd64Server:Version:         1.13.1API version:     1.26 (minimum version 1.12)Package version: docker-1.13.1-68.gitdded712.el7.centos.x86_64Go version:      go1.9.4Git commit:      dded712/1.13.1Built:           Tue Jul 17 18:34:48 2018OS/Arch:         linux/amd64Experimental:    false
[root@localhost ~]#

4、此时 docker 中还只要一个 docker.io/tomcat 镜像，需要重新下载 Mysql 镜像

[root@localhost ~]# docker images
REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE
docker.io/tomcat    8.5.32              5808f01b11bf        3 days ago          463 MB
[root@localhost ~]# docker ps -a
CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS                      PORTS               NAMES
0f6df57a7fa1        tomcat:8.5.32       "catalina.sh run"   44 hours ago        Exited (143) 43 hours ago                       myTtomcat2
d67cca0aacf7        tomcat:8.5.32       "catalina.sh run"   44 hours ago        Exited (143) 43 hours ago                       myTtomcat1
[root@localhost ~]#

Mysql 镜像检索

1、就下载第一个 docker.io/mysql 官方发行版

[root@localhost ~]# docker search mysql
INDEX       NAME                                                             DESCRIPTION                                     STARS     OFFICIAL   AUTOMATED
docker.io   docker.io/mysql                                                  MySQL is a widely used, open-source relati...   6749      [OK]       
docker.io   docker.io/mariadb                                                MariaDB is a community-developed fork of M...   2150      [OK]       
docker.io   docker.io/mysql/mysql-server                                     Optimized MySQL Server Docker images. Crea...   495                  [OK]
docker.io   docker.io/percona                                                Percona Server is a fork of the MySQL rela...   360       [OK]       
docker.io   docker.io/zabbix/zabbix-server-mysql                             Zabbix Server with MySQL database support       114                  [OK]
docker.io   docker.io/hypriot/rpi-mysql                                      RPi-compatible Docker Image with Mysql          93                   
docker.io   docker.io/zabbix/zabbix-web-nginx-mysql                          Zabbix frontend based on Nginx web-server ...   62                   [OK]
docker.io   docker.io/centurylink/mysql                                      Image containing mysql. Optimized to be li...   60                   [OK]
docker.io   docker.io/1and1internet/ubuntu-16-nginx-php-phpmyadmin-mysql-5   ubuntu-16-nginx-php-phpmyadmin-mysql-5          43                   [OK]
docker.io   docker.io/centos/mysql-57-centos7                                MySQL 5.7 SQL database server                   38                   
docker.io   docker.io/mysql/mysql-cluster                                    Experimental MySQL Cluster Docker images. ...   33                   
docker.io   docker.io/tutum/mysql                                            Base docker image to run a MySQL database ...   32                   
docker.io   docker.io/schickling/mysql-backup-s3                             Backup MySQL to S3 (supports periodic back...   20                   [OK]
docker.io   docker.io/bitnami/mysql                                          Bitnami MySQL Docker Image                      16                   [OK]
docker.io   docker.io/zabbix/zabbix-proxy-mysql                              Zabbix proxy with MySQL database support        15                   [OK]
docker.io   docker.io/linuxserver/mysql                                      A Mysql container, brought to you by Linux...   14                   
docker.io   docker.io/centos/mysql-56-centos7                                MySQL 5.6 SQL database server                   9                    
docker.io   docker.io/circleci/mysql                                         MySQL is a widely used, open-source relati...   6                    
docker.io   docker.io/openshift/mysql-55-centos7                             DEPRECATED: A Centos7 based MySQL v5.5 ima...   6                    
docker.io   docker.io/dsteinkopf/backup-all-mysql                            backup all DBs in a mysql server                4                    [OK]
docker.io   docker.io/mysql/mysql-router                                     MySQL Router provides transparent routing ...   2                    
docker.io   docker.io/openzipkin/zipkin-mysql                                Mirror of https://quay.io/repository/openz...   1                    
docker.io   docker.io/ansibleplaybookbundle/mysql-apb                        An APB which deploys RHSCL MySQL                0                    [OK]
docker.io   docker.io/cloudfoundry/cf-mysql-ci                               Image used in CI of cf-mysql-release            0                    
docker.io   docker.io/cloudposse/mysql                                       Improved `mysql` service with support for ...   0                    [OK]
[root@localhost ~]#

2、可以从 Docker Hub 上查看所有 Mysql 的版本，同理也可以查询各个版本使用的详细命令

Mysql 镜像下载

[root@localhost ~]# docker pull mysql:5.5
Trying to pull repository docker.io/library/mysql ... 
5.5: Pulling from docker.io/library/mysql
be8881be8156: Pull complete 
c3995dabd1d7: Pull complete 
9931fdda3586: Pull complete 
bb1b6b6eff6a: Pull complete 
a65f125fa718: Pull complete 
b5332dacc087: Pull complete 
77378af32110: Pull complete 
c863c888ab89: Pull complete 
970e89bcad84: Pull complete 
199374dd7b11: Pull complete 
daf925b4c8c8: Pull complete 
Digest: sha256:973d09f802e90069f4090578bbfb5f1cc095d5c14bdd0bb2651d5e448751f907
Status: Downloaded newer image for docker.io/mysql:5.5
[root@localhost ~]# docker images
REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE
docker.io/tomcat    8.5.32              5808f01b11bf        3 days ago          463 MB
docker.io/mysql     5.5                 c43b4117afc4        2 weeks ago         205 MB
[root@localhost ~]#

Mysql 容器运行

错误运行方式

1、如下所示演示的是 Mysql 镜像运行时没有指定密码而导致异常退出启动失败的情况

2、通过 docker logs container-name/container-id 命令查看日志已经提醒的很明显了，必须指定 root 密码、或者允许密码为空、或者使用随机密码

3、最后将此错误的容器删除掉：docker rm container-id

[root@localhost ~]# docker images
REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE
docker.io/tomcat    8.5.32              5808f01b11bf        3 days ago          463 MB
docker.io/mysql     5.5                 c43b4117afc4        2 weeks ago         205 MB
[root@localhost ~]# docker run --name mysql01 -d mysql:5.5
fb1c96d110c715034c263185e40f066dc688e2284c02c250243e25c017cf872b
[root@localhost ~]# docker ps -a
CONTAINER ID        IMAGE               COMMAND                  CREATED             STATUS                      PORTS               NAMES
fb1c96d110c7        mysql:5.5           "docker-entrypoint..."   9 seconds ago       Exited (1) 6 seconds ago                        mysql01
0f6df57a7fa1        tomcat:8.5.32       "catalina.sh run"        44 hours ago        Exited (143) 43 hours ago                       myTtomcat2
d67cca0aacf7        tomcat:8.5.32       "catalina.sh run"        44 hours ago        Exited (143) 43 hours ago                       myTtomcat1
[root@localhost ~]# docker logs fb1c96d110c7
error: database is uninitialized and password option is not specified You need to specify one of MYSQL_ROOT_PASSWORD, MYSQL_ALLOW_EMPTY_PASSWORD and MYSQL_RANDOM_ROOT_PASSWORD
[root@localhost ~]# docker rm fb1c96d110c7
fb1c96d110c7
[root@localhost ~]# docker ps -a
CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS                      PORTS               NAMES
0f6df57a7fa1        tomcat:8.5.32       "catalina.sh run"   44 hours ago        Exited (143) 43 hours ago                       myTtomcat2
d67cca0aacf7        tomcat:8.5.32       "catalina.sh run"   44 hours ago        Exited (143) 43 hours ago                       myTtomcat1
[root@localhost ~]#

正确运行方式

1、Docker Hub 上 Mysq 官方提供的启动命令如下所示，需要使用 -e 参数指定 roor 账户密码进行启动：

$ docker run --name some-mysql -e MYSQL_ROOT_PASSWORD=my-secret-pw -d mysql:tag

[root@localhost ~]# docker run --name mysql01 -e MYSQL_ROOT_PASSWORD=root -d mysql:5.5
3a896a0867265c59d84d209a93d60f3d837b4667c649981eb3933e997a459c55
[root@localhost ~]# docker ps -a
CONTAINER ID        IMAGE               COMMAND                  CREATED             STATUS                      PORTS               NAMES
3a896a086726        mysql:5.5           "docker-entrypoint..."   3 seconds ago       Up 2 seconds                3306/tcp            mysql01
0f6df57a7fa1        tomcat:8.5.32       "catalina.sh run"        44 hours ago        Exited (143) 43 hours ago                       myTtomcat2
d67cca0aacf7        tomcat:8.5.32       "catalina.sh run"        44 hours ago        Exited (143) 43 hours ago                       myTtomcat1
[root@localhost ~]#

2、如上所示，此时 mysql 容器运行是成功的，但是《 Docker 容器操作常用命令》中已经说过，此时启动的 3306 端口是 Mysql 镜像在容器内部的端口，外部访问必须进行端口映射，再次删除此无效的容器。

[root@localhost ~]# docker stop 3a896a086726
3a896a086726
[root@localhost ~]# docker rm 3a896a086726
3a896a086726
[root@localhost ~]# docker ps -a
CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS                      PORTS               NAMES
0f6df57a7fa1        tomcat:8.5.32       "catalina.sh run"   44 hours ago        Exited (143) 43 hours ago                       myTtomcat2
d67cca0aacf7        tomcat:8.5.32       "catalina.sh run"   44 hours ago        Exited (143) 43 hours ago                       myTtomcat1
[root@localhost ~]#

端口映射

1、端口映射加上 -p 参数即可，可以参考《 Docker 容器操作常用命令》，因为 CentOS 服务器本身外部已经安装了 Mysql 已经占用了 3306 端口，所以使用 3307 映射 Docker 容器中的 3306 端口

[root@localhost ~]# docker run --name mysql01 -e MYSQL_ROOT_PASSWORD=root -p 3307:3306 -d mysql:5.5
2aad1d2a8e76261715ac0f1d4ef03217ae54866db479d26b81364a39e2ec3801
[root@localhost ~]# netstat -ntlpu
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address           Foreign Address         State       PID/Program name    
tcp        0      0 0.0.0.0:22              0.0.0.0:*               LISTEN      1041/sshd           
tcp        0      0 127.0.0.1:25            0.0.0.0:*               LISTEN      1188/master         
tcp6       0      0 :::33060                :::*                    LISTEN      1308/mysqld         
tcp6       0      0 :::3306                 :::*                    LISTEN      1308/mysqld         
tcp6       0      0 :::3307                 :::*                    LISTEN      2892/docker-proxy-c 
tcp6       0      0 :::22                   :::*                    LISTEN      1041/sshd           
tcp6       0      0 ::1:25                  :::*                    LISTEN      1188/master         
udp        0      0 0.0.0.0:68              0.0.0.0:*                           857/dhclient        
[root@localhost ~]# docker ps -a
CONTAINER ID        IMAGE               COMMAND                  CREATED             STATUS                      PORTS                    NAMES
2aad1d2a8e76        mysql:5.5           "docker-entrypoint..."   14 seconds ago      Up 14 seconds               0.0.0.0:3307->3306/tcp   mysql01
0f6df57a7fa1        tomcat:8.5.32       "catalina.sh run"        44 hours ago        Exited (143) 44 hours ago                            myTtomcat2
d67cca0aacf7        tomcat:8.5.32       "catalina.sh run"        44 hours ago        Exited (143) 43 hours ago                            myTtomcat1
[root@localhost ~]#

2、如上所示做了端口映射后，就可以从外部访问 Docker 容器内部的 Mysql 了，但是如果要从 CentOS 服务器外部访问，则还需要 CentOS 服务器开放 3307 端口

[root@localhost ~]# firewall-cmd --zone=public --list-port
9876/tcp 8090/tcp 80/tcp 8080/tcp
[root@localhost ~]# firewall-cmd --zone=public --add-port=3307/tcp --permanent
success
[root@localhost ~]# firewall-cmd --reload
success
[root@localhost ~]# firewall-cmd --zone=public --list-port
9876/tcp 8090/tcp 80/tcp 8080/tcp 3307/tcp
[root@localhost ~]#