Skip to content

Docker.md

Latest commit

 

History

History
233 lines (196 loc) · 6.58 KB

Docker.md

File metadata and controls

233 lines (196 loc) · 6.58 KB

Docker Overview

Docker is a container management service. The keywords of Docker are develop, ship and run anywhere. The whole idea of Docker is for developers to easily develop applications, ship them into containers which can then be deployed anywhere.

  • How to start docker service
systemctl start docker
  • How to check docker service status
systemctl status docker
  • How to check docker version
docker version
  • How to check more information about docker
docker info
  • How to check network details associated with docker
ifconfig -a
  • How to check all images available
docker images
docker images ls
  • How to check all containers available
docker ps 
docker container ls
  • How to check all container network available
docker network ls
  • How to check docker volume available
docker volume ls
  • How to create a container
docker run <imagename>
  • How to pull an image
docker pull <imagename>
  • how to search an image on dockerhub
docker search <imagename>
  • Delete container after you stop
docker run -
  • docker system
Commands:
  df          Show docker disk usage
  events      Get real time events from the server
  info        Display system-wide information
  prune       Remove unused data
  • docker containers
 Commands:
  attach      Attach to a running container
  commit      Create a new image from a container's changes
  cp          Copy files/folders between a container and the local filesystem
  create      Create a new container
  diff        Inspect changes on a container's filesystem
  exec        Run a command in a running container
  export      Export a container's filesystem as a tar archive
  inspect     Display detailed information on one or more containers
  kill        Kill one or more running containers
  logs        Fetch the logs of a container
  ls          List containers
  pause       Pause all processes within one or more containers
  port        List port mappings or a specific mapping for the container
  prune       Remove all stopped containers
  rename      Rename a container
  restart     Restart one or more containers
  rm          Remove one or more containers
  run         Run a command in a new container
  start       Start one or more stopped containers
  stats       Display a live stream of container(s) resource usage statistics
  stop        Stop one or more running containers
  top         Display the running processes of a container
  unpause     Unpause all processes within one or more containers
  update      Update configuration of one or more containers
  wait        Block until one or more containers stop, then print their exit codes
  • How to save an image in tar file
docker save <image name> >filename.tar
  • How to load an existing an image
docker load <tar file>

docker import file.tar newimage

Explanation about Load /Save import/export and commmit

  • save works with Docker images. It saves everything needed to build a container from scratch. Use this command if you want to share an image with others.

  • load works with Docker images. Use this command if you want to run an image exported with save. Unlike pull, which requires connecting to a Docker registry, load can import from anywhere (e.g. a file system, URLs).

  • export works with Docker containers, and it exports a snapshot of the container’s file system. Use this command if you want to share or back up the result of building an image.

  • import works with the file system of an exported container, and it imports it as a Docker image. Use this command if you have an exported file system you want to explore or use as a layer for a new image.

Add below permission if the jenkins is not able to run docker command

sudo chmod 666 /var/run/docker.sock

Optional

Deploy two tier Application on docker

  • Clone the repository from github using below command
git clone https://github.com/monbostest/java-code1.git
  • Create a war file using(maven image) below command
cd java-code1
docker run -it --rm --name my-maven-project -v "$(pwd)":/usr/src/mymaven -w /usr/src/mymaven maven:3.3-jdk-8 mvn clean install

NOTE You will have a target folder created where your war file will be stored.

  • Create a tomcat container
docker run -d -p 8888:8080 tomcat
  • Copy the war file to /usr/local/tomcat/webapps using below command
docker cp  /target/<*.war file >dockerid:/usr/local/tomcat/webapps

NOTE Now please if you are able to access your application in your browser

IPaddress:8888/studentapp-2.5-SNAPSHOT/

####### Configuring Backend (MySql Database to store user details)

  • Create Mysql Container using below command
docker run -d -e MYSQL_ROOT_PASSWORD=root mysql:5.6
  • Create database
docker exec -it <container-id> sh
mysql -u root -p
create database studentapp;
use studentapp;

CREATE TABLE Students(student_id INT NOT NULL AUTO_INCREMENT,
student_name VARCHAR(100) NOT NULL,
student_addr VARCHAR(100) NOT NULL,
student_age VARCHAR(3) NOT NULL,
student_qual VARCHAR(20) NOT NULL,
student_percent VARCHAR(10) NOT NULL,
student_year_passed VARCHAR(10) NOT NULL,
PRIMARY KEY (student_id)
);

grant all privileges on studentapp.* to 'student'@'%' identified by 'student@1';

flush privileges;

NOW we are ready with Frontend and backend service .

To make a connection b/w Application with Database you need to install mysql connector in tomcat container.

  • use below command to have mysql connector after login to tomcat container
cd lib
wget https://github.com/cit-latex/stack/raw/master/mysql-connector-java-5.1.40.jar
  • Make database entry
apt-get update
apt-get install vim -y
Add the following content just before last line
vim conf/context.xml
<Resource name="jdbc/TestDB" auth="Container" type="javax.sql.DataSource"
               maxTotal="100" maxIdle="30" maxWaitMillis="10000"
               username="student" password="student@1" driverClassName="com.mysql.jdbc.Driver"
               url="jdbc:mysql://<IP-ADDRESS-OF-DB-SERVER>:3306/studentapp"/>
  • Restart your application container
docker restart <container-id>

Now Verify if you are able to upload the data to your database using application

  • convert running container into an image
docker commit <container id>
  • check image
docker images
  • login to docker hub
docker login
  • Create a repository on dockerhub
  • Tag your image
  • Push your image to dockerhub