Dockerfile theory + practice!!!

  Dockerfile is the description file of the image file in docker. The straight white point is exactly what the image file is composed of step by step.
  for example: you bought a hanger on Taobao, but the seller did not send you a complete hanger, but some components and a drawing. You assemble the hanger step by step according to the drawing, and it will become the appearance you need. Then the dockerfile is the drawing, and the image file is the hanger you need. Dockerfile is not recommended to be named casually, just dockerfile.
  therefore, the Dockerfile contains instructions, each of which builds a layer. Therefore, the content of each instruction is to describe how the layer should be built.

(1) docker runs a container from the basic image;
(2) Execute an instruction and make changes to the container;
(3) Perform the operation similar to docker commit to submit a new image layer;
(4) docker then runs a new container based on the newly submitted image;
(5) Execute the next instruction in the dockerfile until all instructions are executed.

1. Dockerfile: it is the raw material of the software. You need to define a dockerfile, which defines everything the process needs. The contents of dockerfile include execution code or file, environment variable, dependency package, runtime environment, dynamic link library, etc;

2. Docker image: it is the delivery of software. After defining a file with Dockerfile, a docker image will be generated when docker is built. When docker image is running, services will be provided;

3. Docker container: it can be considered as the running state of software, and the container provides services directly.

1. Building sshd image

[root@localhost ~]# cd /opt/ [root@localhost opt]# mkdir sshd ##Create directory [root@localhost opt]# cd sshd/ [root@localhost sshd]# vim Dockerfile ##Write a dockerfile file FROM centos ##Download mirroring MAINTAINER this is sshd <xu> ##Descriptive information RUN yum -y update RUN yum -y install openssh* net-tools lsof telnet passwd RUN echo '123456' | passwd --stdin root RUN sed -i 's/UsePAM yes/UsePAM no/g' /etc/ssh/sshd_config RUN ssh-keygen -t rsa -f /etc/ssh/ssh_host_rsa_key RUN sed -i '/^session\s\+required\s\+pam_loginuid.so/s/^/#/' /etc/pam.d/sshd RUN mkdir -p /root/.ssh && chown root.root /root && chmod 700 /root/.ssh EXPOSE 22 ##port CMD ["/usr/sbin/sshd" , "-D"] [root@localhost sshd]# docker build -t sshd:new . ##create mirror 89432272695ab560b18de75a064428e4a7c4a52dfce223afd2e85132ae6c3c72 [root@localhost sshd]# docker run -d -P sshd:new ##Create maps and containers [root@localhost sshd]# docker ps -a ##View container status CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 89432272695a sshd:new "/usr/sbin/sshd -D" 7 seconds ago Up 6 seconds 0.0.0.0:32768->22/tcp sad_fermi [root@localhost sshd]# ssh localhost -p 32768 ##Log in locally with ssh

2. Build system CTL image

[root@localhost ~]# cd /opt/ [root@localhost opt]# mkdir systemctl ##Create directory [root@localhost opt]# cd systemctl/ [root@localhost systemctl]# vim Dockerfile ##Write a dockerfile file FROM sshd:new ENV container docker ##Environmental Science 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/*; VOLUME [ "/sys/fs/cgroup" ] CMD ["/usr/sbin/init"] [root@localhost systemctl]# docker build -t systemd:lasted . ##create mirror [root@localhost systemctl]# docker run --privileged -it -v /sys/fs/cgroup/:/sys/fs/cgroup:ro systemd:lasted /sbin/init ##The root in the private container has the real root permission. Otherwise, the root in the container is only a common external user permission. [root@localhost ~]# docker exec -it 23a50d568c75 bash ##Container entry [root@23a50d568c75 /]# systemctl status sshd ##View state

3. Build Nginx image

[root@localhost ~]# cd /opt/ [root@localhost opt]# mkdir nginx ##Create Nginx directory [root@localhost opt]# cd nginx/ [root@localhost nginx]# vim Dockerfile FROM centos:7 MAINTAINER The is nginx <xu> RUN yum install -y proc-devel gcc gcc-c++ zlib zlib-devel make openssl-devel wget ADD nginx-1.12.2.tar.gz /usr/local WORKDIR /usr/local/nginx-1.12.2/ RUN ./configure --prefix=/usr/local/nginx && make && make install EXPOSE 80 EXPOSE 443 RUN echo "daemon off;">>/usr/local/nginx/conf/nginx.conf WORKDIR /root/nginx ADD run.sh /run.sh RUN chmod 755 /run.sh CMD ["/run.sh"] [root@localhost nginx]# vim run.sh #!/bin/bash /usr/local/nginx/sbin/nginx ##Start Nginx service [root@localhost nginx]# mount.cifs //192.168.100.3/LNMP-C7 /mnt / ාා񖓿ාmount image Password for root@//192.168.100.3/LNMP-C7: [root@localhost nginx]# cp /mnt/nginx-1.12.2.tar.gz ./ ##Copy to current directory [root@localhost nginx]# docker build -t nginx:new . ##create mirror [root@localhost nginx]# docker run -d -P nginx:new ##Create container 228c1f5b8070d52c6f19d03159ad93a60d682a586c0b1f944dc651ee40576a3e [root@localhost nginx]# docker ps -a ##View container CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 228c1f5b8070 nginx:new "/run.sh" 9 seconds ago Up 8 seconds 0.0.0.0:32770->80/tcp, 0.0.0.0:32769->443/tcp busy_booth

Accessing web pages with browser

4. Building Tomcat image

[root@localhost opt]# mkdir tomcat [root@localhost opt]# cd tomcat [root@localhost tomcat]# cp /mnt/tomcat/jdk-8u91-linux-x64.tar.gz ./ ##Copy to current directory [root@localhost tomcat]# cp /mnt/Tomcat1/tomcat/apache-tomcat-9.0.16.tar.gz ./ [root@localhost tomcat]# vim Dockerfile FROM centos:7 MAINTAINER this is tomcat ADD jdk-8u91-linux-x64.tar.gz /usr/local WORKDIR /usr/local RUN mv jdk1.8.0_91 /usr/local/java ENV JAVA_HOME /usr/local/java ##Setting environment variables ENV JAVA_BIN /usr/local/java/bin ENV JRE_HOME /usr/local/java/jre ENV PATH $PATH:/usr/local/java/bin:/usr/local/java/jre/bin ENV CLASSPATH /usr/local/java/jre/bin:/usr/local/java/lib:/usr/local/java/jre/lib/charsets.jar ADD apache-tomcat-8.5.16.tar.gz /usr/local WORKDIR /usr/local RUN mv apache-tomcat-8.5.16 /usr/local/tomcat8 EXPOSE 8080 ENTRYPOINT ["/usr/local/tomcat8/bin/catalina.sh","run"] [root@localhost tomcat]# docker build -t tomcat:centos . ##create mirror [root@localhost tomcat]# docker run --name tomcat01 -p 1234:8080 -it tomcat:centos /bin/bash ##Create container

Access with browser

5. Building MySQL image

[root@localhost opt]# mkdir mysql [root@localhost opt]# cd mysql [root@localhost mysql]# cp /mnt/mysql-boost-5.7.20.tar.gz ./ ##Copy the compressed package to the current directory [root@localhost mysql]# vim my.cnf ##Create profile template in current directory [client] port = 3306 default-character-set=utf8 socket = /usr/local/mysql/mysql.sock [mysql] port = 3306 default-character-set=utf8 socket = /usr/local/mysql/mysql.sock [mysqld] user = mysql basedir = /usr/local/mysql datadir = /usr/local/mysql/data port = 3306 character_set_server=utf8 pid-file = /usr/local/mysql/mysqld.pid socket = /usr/local/mysql/mysql.sock server-id = 1 sql_mode=NO_ENGINE_SUBSTITUTION,STRICT_TRANS_TABLES,NO_AUTO_CREATE_USER,NO_AUTO_VALUE_ON_ZERO,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,PIPES_AS_CONCAT,ANSI_QUOTES [root@localhost mysql]# vim Dockerfile ##Write a dockerfile file FROM centos:7 RUN yum -y install \ ncurses \ ncurses-devel \ bison \ cmake \ make \ gcc \ gcc-c++ RUN useradd -s /sbin/nologin mysql ADD mysql-boost-5.7.20.tar.gz /usr/local/src WORKDIR /usr/local/src/mysql-5.7.20/ RUN cmake \ -DCMAKE_INSTALL_PREFIX=/usr/local/mysql \ -DMYSQL_UNIX_ADDR=/usr/local/mysql/mysql.sock \ -DSYSCONFDIR=/etc \ -DSYSTEMD_PID_DIR=/usr/local/mysql \ -DDEFAULT_CHARSET=utf8 \ -DDEFAULT_COLLATION=utf8_general_ci \ -DWITH_INNOBASE_STORAGE_ENGINE=1 \ -DWITH_ARCHIVE_STORAGE_ENGINE=1 \ -DWITH_BLACKHOLE_STORAGE_ENGINE=1 \ -DWITH_PERFSCHEMA_STORAGE_ENGINE=1 \ -DMYSQL_DATADIR=/usr/local/mysql/data \ -DWITH_BOOST=boost \ -DWITH_SYSTEMD=1 && make && make install RUN chown -R mysql:mysql /usr/local/mysql/ RUN rm -rf /etc/my.cnf ADD my.cnf /etc RUN chown mysql:mysql /etc/my.cnf ENV PATH=/usr/local/mysql/bin:/usr/local/mysql/lib:$PATH WORKDIR /usr/local/mysql/ RUN bin/mysqld \ --initialize-insecure \ --user=mysql \ --basedir=/usr/local/mysql \ --datadir=/usr/local/mysql/data RUN cp /usr/local/mysql/usr/lib/systemd/system/mysqld.service /usr/lib/systemd/system/ EXPOSE 3306 RUN echo -e "#!/bin/sh \nsystemctl enable mysqld" > /run.sh RUN chmod 755 /run.sh RUN sh /run.sh CMD ["init"] [root@localhost mysql]# docker build -t centos:mysql . ##create mirror [root@localhost mysql]# docker run --name=mysql_server -d -P --privileged centos:mysql ##Create container [root@localhost mysql]# docker ps -a CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 998dc9797102 centos:mysql "init" About a minute ago Up About a minute 0.0.0.0:32768->3306/tcp mysql_server [root@localhost mysql]# docker exec -it 998dc9797102 /bin/bash [root@998dc9797102 mysql]# mysql mysql> grant all privileges on *.* to 'root'@'%' identified by 'abc123'; mysql> grant all privileges on *.* to 'root'@'localhost' identified by 'abc123'; [root@localhost ~]# mysql -h 192.168.13.128 -u root -P 32768 -pabc123 Welcome to the MariaDB monitor. Commands end with ; or \g. Your MySQL connection id is 4 Server version: 5.7.20 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)]>

15 January 2020, 03:25 | Views: 2949