Dockerfile制作镜像实战

Posted 2020-11-27

还不了解什么是Dockerfile的小伙伴可以查看我之前的博客：
https://blog.51cto.com/14557905/2489466
Dockerfile镜像制作实战
Dockerfile制作镜像的三个步骤

一、制作sshd镜像
1.编写Dockerfile文件

[root@docker sshd]# vim Dockerfile
#基础镜像
FROM centos:7
#用户信息
MAINTAINER this is sshd project
#基于基础镜像系统更新，软件安装
RUN yum -y update
RUN yum -y install openssh* net-tools lsof telnet passwd
#设置用户密码
RUN echo ‘123456‘ | passwd --stdin root
#关闭PAM认证
RUN sed -i ‘s/UsePAM yes/UsePAM no/g‘ /etc/ssh/sshd_config
#添加非对称密钥
RUN ssh-keygen -t rsa -f /etc/ssh/ssh_host_rsa_key
#关闭pam会话模块
RUN sed -i ‘/^sessions+requieds+pam_loginuid.so/s/^/#/‘ /etc/pam.d/sshd
#创建ssh工作目录，设置权限
RUN mkdir -p /root/.ssh && chown root.root /root && chmod 700 /root/.ssh
#设置端口号
EXPOSE 22
#启动容器时执行操作
CMD ["/usr/sbin/sshd","-D"]

2.创建镜像

[root@docker sshd]# docker build -t sshd:new .
[root@docker sshd]# docker images
REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE
sshd                new                 43e794cf8abd        19 seconds ago      585MB
centos              7                   5e35e350aded        5 months ago        203MB

3.创建容器验证

[root@docker sshd]# docker run -d -P sshd:new 
[root@docker sshd]# docker ps -a
CONTAINER ID        IMAGE               COMMAND               CREATED             STATUS              PORTS                   NAMES
99cd8001ff28        sshd:new            "/usr/sbin/sshd -D"   4 seconds ago       Up 3 seconds        0.0.0.0:32768->22/tcp   compassionate_beaver
#宿主机使用ssh登陆容器
[root@docker sshd]# ssh localhost -p 32768
The authenticity of host ‘[localhost]:32768 ([::1]:32768)‘ can‘t be established.
RSA key fingerprint is SHA256:DND5bet+Io1sjjiKpNS6BvoeJC+YD07ejhRcp7s8VtQ.
RSA key fingerprint is MD5:a4:0e:3d:5a:18:1e:b2:17:85:f6:df:a5:ce:ab:d2:82.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added ‘[localhost]:32768‘ (RSA) to the list of known hosts.
root@localhost‘s password: 
[root@2a9bcdd7681f ~]#

二、创建systemctl镜像
创建完成sshd镜像后，无法使用systemctl status sshd命令查看ssh状态，可以根据sshd的镜像添加systemctl功能
1.编写Dockerfile文件

[root@docker systemctl]# vim Dockerfile
#基础镜像
FROM sshd:new
#设置环境变量
ENV container docker
#进入指定目录，用for循环遍历目录下所有文件并删除指定文件
RUN (cd /lib/systemd/system/sysinit.target.wants/; for i in *; do [ $i == systemd-tmpfiles-setup.service ] || rm -f $i; done); rm -f /lib/systemd/system/multi-user.target.wants/*; rm -f /etc/systemd/system/*.wants/*; rm -f /lib/systemd/system/local-fs.target.wants/*; rm -f /lib/systemd/system/sockets.target.wants/*udev*; rm -f /lib/systemd/system/sockets.target.wants/*initctl*; rm -f /lib/systemd/system/basic.target.wants/*; rm -f /lib/systemd/system/anaconda.target.wants/*;
#挂载宿主机的cgrups卷，以便执行容器
VOLUME ["/sys/fs/cgroup"]
#执行初始化命令
CMD ["/usr/sbin/init"]

2.创建镜像

[root@docker systemctl]# docker build -t systemctl:new .
[root@docker systemctl]# docker images
REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE
systemctl           new                 b029bbbd8a6b        9 minutes ago       585MB
sshd                new                 4b69240205be        33 minutes ago      585MB
centos              7                   5e35e350aded        5 months ago        203MB

3.创建容器验证

[root@docker systemctl]# docker run --privileged -it -v /sys/fs/cgroup/:/sys/fs/cgroup:ro systemctl:new /sbin/init
[root@docker ~]# docker ps -a
CONTAINER ID        IMAGE               COMMAND               CREATED             STATUS              PORTS                   NAMES
d98f478ccaf3        systemctl:new       "/sbin/init"      2 minutes ago       Up 2 minutes        22/tcp                  practical_fermat
[root@docker ~]# docker exec -it d98f478ccaf3 bash
#可正常使用systemctl命令查看
[root@d98f478ccaf3 /]# systemctl status sshd
● sshd.service - OpenSSH server daemon
   Loaded: loaded (/usr/lib/systemd/system/sshd.service; disabled; vendor preset: enabled)
   Active: inactive (dead)
     Docs: man:sshd(8)
           man:sshd_config(5)

三、创建nginx镜像（手工编译）
1.编写dockerfile文件

[root@docker nginx]# vim Dockerfile
  #基础镜像
FROM centos:7
  #用户信息
MAINTAINER This is Nginx test
  #基于基础镜像系统更新，环境包安装
RUN yum -y update
RUN yum -y install make gcc gcc-c++ pcre-devel zlib-devel tar
  #创建nginx用户
RUN useradd -M -s /sbin/nologin nginx
  #上传nginx软件包，解压(使用ADD选项可以直接解压上传的包)
COPY nginx-1.12.2.tar.gz /opt/
RUN tar zxvf /opt/nginx-1.12.2.tar.gz -C /opt
  #在指定目录下，开始编译安装nginx
WORKDIR /opt/nginx-1.12.2/
RUN ./configure --prefix=/usr/local/nginx --user=nginx --group=nginx --with-http_stub_status_module
RUN make && make install
  #设置环境变量
ENV PATH /usr/local/nginx/sbin:$PATH
  #指定端口
EXPOSE 80
#修改Nginx配置文件，以非daemon方式启动
RUN echo "daemon off;" >> /usr/local/nginx/conf/nginx.conf
#添加运行脚本，设置权限
ADD run.sh /run.sh
RUN chmod 755 /run.sh
#指定容器开启时执行的脚本
CMD ["/run.sh"]

2.编写run.sh启动脚本，将nginx软件包上传

[root@docker nginx]# vim run.sh
#!/bin/bash
/usr/local/nginx/sbin/nginx

3.创建镜像

[root@docker nginx]# docker build -t nginx:new .
[root@docker nginx]# docker images
REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE
nginx               new                 24b44e614799        14 seconds ago      585MB
centos              7                   5e35e350aded        5 months ago        203MB

4.创建容器验证

#创建容器，随机生成映射端口
[root@docker nginx]# docker run -d -P nginx:new 
#查看容器及映射的端口号
[root@docker nginx]# docker ps -a
CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS              PORTS                   NAMES
b51160232ad8        nginx:new           "/run.sh"           4 seconds ago       Up 3 seconds        0.0.0.0:32775->80/tcp   sad_rhodes

浏览器中访问验证

四、创建Tomcat镜像
1.编写Dockerfile文件

[root@docker tomcat]# vim Dockerfile 
#基础镜像
FROM centos:7
#用户信息
MAINTAINER Tomcat test
#基于基础镜像更新系统
RUN yum -y update
#安装java环境包
COPY jdk-8u201-linux-x64.rpm /opt/
RUN rpm -ivh /opt/jdk-8u201-linux-x64.rpm
#设置java的环境变量
ENV JAVA_HOME /usr/java/jdk1.8.0_201-amd64
ENV CLASSPATH $JAVA_HOME/lib/tools.jar:$JAVA_HOME/lib/dt.jar
ENV PATH $JAVA_HOME/bin:$PATH
#安装tomcat
ADD apache-tomcat-9.0.16.tar.gz /opt/tomcat
RUN mv /opt/tomcat/apache-tomcat-9.0.16/ /usr/local/tomcat
#指定端口
EXPOSE 8080
#指定容器启动时的操作，此处的ENTERYPOINT也可更换为CMD
ENTRYPOINT ["/usr/local/tomcat/bin/catalina.sh","run"]

2.将所需安装包上传至当前目录下

[root@docker tomcat]# ls
apache-tomcat-9.0.16.tar.gz  Dockerfile  jdk-8u201-linux-x64.rpm

3.镜像制作

[root@docker tomcat]# docker build -t tomcat:new .
[root@docker tomcat]# docker images
REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE
tomcat              new                 8b86bbc483a4        3 minutes ago       981MB
centos              7                   5e35e350aded        5 months ago        203MB

4.创建容器验证

[root@docker tomcat]# docker run -d -P tomcat:new 
[root@docker tomcat]# docker ps -a
CONTAINER ID        IMAGE               COMMAND                  CREATED             STATUS              PORTS                     NAMES
3d94d5eddca0        tomcat:new          "/usr/local/tomcat/b…"   3 seconds ago       Up 2 seconds        0.0.0.0:32776->8080/tcp   optimistic_dubinsk

5.在浏览器上访问验证

创建mysql镜像
1.编写Dockerfile文件

[root@docker mysql]# vim Dockerfile
#基础镜像
FROM centos:7
#用户信息
MAINTAINER This is MySQL Project
#基于基础镜像系统更新和环境包安装
RUN yum -y update
RUN yum install -y ncurses-devel autoconf cmake gcc gcc-c++ make pcre-devel expat-devel pcre
#添加mysql-5.6安装包
ADD mysql-5.6.26.tar.gz /opt
#进入指定目录编译安装mysql
WORKDIR /opt/mysql-5.6.26
RUN cmake -DCMAKE_INSTALL_PREFIX=/usr/local/mysql -DDEFAULT_CHARSET=utf8 -DDEFAULT_COLLATION=utf8_general_ci -DEXTRA_CHARSETS=all -DSYSCONFIDIR=/etc -DMYSQL_DATADIR=/home/mysql/ -DMYSQL_UNIX_ADDR=/home/mysql/mysql.sock
RUN make && make install
#添加mysql配置文件
RUN rm -f /etc/my.cnf
RUN cp /opt/mysql-5.6.26/support-files/my-default.cnf /etc/my.cnf
#添加mysql的启动脚本，设置权限
RUN cp /opt/mysql-5.6.26/support-files/mysql.server /etc/init.d/mysqld
RUN chmod 755 /etc/init.d/mysqld
#设置环境变量
ENV PATH $PATH:/usr/local/mysql/bin
#创建mysql用户，更改mysql安装目录的权限
RUN useradd -s /sbin/nologin mysql
RUN chown -R mysql:mysql /usr/local/mysql/
#初始化数据库
RUN /usr/local/mysql/scripts/mysql_install_db --user=mysql --ldata=/var/lib/mysql --basedir=/usr/local/mysql --datadir=/home/mysql
#建立sock文件软连接，更改启动脚本文件
RUN ln -s /var/lib/mysql/mysql.sock  /home/mysql/mysql.sock
RUN sed -i ‘46 s/basedir=/basedir=/usr/local/mysql/‘ /etc/init.d/mysqld
RUN sed -i ‘47 s/datadir=/datadir=/home/mysql/‘ /etc/init.d/mysqld
#指定端口
EXPOSE 3306
#指定容器启动时的操作
CMD ["mysqld_safe"]

2.将安装包上传到当前目录

[root@docker mysql]# ls
Dockerfile  mysql-5.7.26.tar.gz

3.创建镜像

[root@docker mysql]# docker build -t mysqld:new .
[root@docker mysql]# docker images
REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE
mysqld              new                 9b2703bd15c0        54 minutes ago      5.11GB
centos              7                   5e35e350aded        5 months ago        203MB

4.创建容器验证

[root@docker mysql]# docker run -d -P mysqld:new 
[root@docker mysql]# docker ps -a
CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS              PORTS                     NAMES
fff4ac6a524f        mysqld:new          "mysqld_safe"       4 seconds ago       Up 3 seconds        0.0.0.0:32777->3306/tcp   infallible_babbage
#进入容器设置mysql的权限账户
[root@docker mysql]# docker exec -it fff4ac6a524f /bin/bash
[root@fff4ac6a524f ~]# mysql -uroot -p
mysql> grant all privileges on *.* to ‘root‘@‘localhost‘ identified by ‘123456‘;
mysql> grant all privileges on *.* to ‘root‘@‘%‘ identified by ‘123456‘;
#在宿主机安装mysql客户端测试验证
[root@docker mysql]# yum install mariadb -y
[root@docker ~]# mysql -h 192.168.7.168 -uroot -p123456 -P 32777
Welcome to the MariaDB monitor.  Commands end with ; or g.
Your MySQL connection id is 2
Server version: 5.7.26 Source distribution

Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.

Type ‘help;‘ or ‘h‘ for help. Type ‘c‘ to clear the current input statement.

MySQL [(none)]>

总结：
以上就是一些常用的Dockerfile创建镜像的案例，在使用Dockerfile创建镜像时，最重要就是编写dockerfile文件的过程，我们需要知道每一步操作的意义，而且要细心不能因为当中一些正则表达式的使用而出错。