simple-devops-project-4

Simple DevOps Project 4

From the project we are AIM to deploy webapp_demo app on docker host with ansible playbook. The developer will develop code and push to github with git, creating Jenkin CI / CD job to build the .war file with Maven and coping .war file to Ansible host, creating a docker tomcat image by including copied .war file on Ansible host and push to docker hub repo. Finally docker host pulls the docker tomcat image from docker hub repo and deploy on 8080 port.

Pre-Requirments

• Jenkins with Maven Server
• Ansible server
• Docker server
• Install Publish over SSH Plugin
• Enable Connection between Ansible and Jenkins
• Setup Ansible to Docker host passwordless connection
• Create account on Docker Hub and Configure login on Ansible and Docker host with dockeradmin user

Install Publish over SSH plugin

Jenkins Dashboard >> Manage Jenkins > Manage Plugins > Available > Publish over SSH and click install without restat button

Enable Connection between Ansible and Jenkins

Jenkins Dashboard >> Manage Jenkins > Configure System > Publish Over SSH > SSH Servers

• SSH Servers:
  • Name : ansible_host
  • Hostname: <ansible_ServerIP>
  • username: ansadmin
  • password: *******

Test the connection by clicking Test Connection and save

Setup Ansible to Docker host passwordless connection

• Create dockeradmin user, add to docker group on both ansible and docker hosts

sudo useradd dockeradmin
sudo passwd dockeradmin
sudo usermod -aG docker dockeradmin

• Add to dockeradmin to sudoer on both Ansible and Docker hosts.

echo "dockeradmin	ALL=(ALL:ALL) NOPASSWD: ALL" >> /etc/sudoers

• Uncommnet PasswordAuthentication option set to yes in /etc/ssh/sshd_config on both Ansible and Docker hosts as followss

sudo vi /etc/ssh/sshd_config
#uncomment and change the below option to 'no' to 'yes'
PasswordAuthentication yes

• Login to Ansible server as dockeradmin user generate SSH key and copy to docker host.

su dockeradmin
ssh-keygen
ssh-copy-id dockeradmin@<docker-host-IP>

Create an docker image

• Login to Jenkins portal
• Create Jenkins job, Fill the following details,
  • Source Code Management:
    • Repository : https://github.com/ValaxyTech/hello-world.git
    • Branches to build: */master
  • Build:
    • Root ROM: pom.xml
    • Goals and options: clean install package
  • Post Steps:
    • Send files or execute commands over SSH
      • Name: ansible_server
      • Source files : webapp/target/*.war
      • Remove prefix : webapp/target
      • Remote directory : //opt//docker
  • Send files or execute commands over SSH
    • Name: ansible_server
    • Source files : Dockerfile
    • Remote directory : //opt//docker
    • Exec Command:

      cd /opt/docker
      docker build -t webapp_demo .
      docker tag webapp_demo mkn400/valaxy_demo
      docker push mkn400/webapp_demo
      docker rmi webapp_demo mkn400/webapp_demo

  • Login to Docker host and check images and containers. (no images and containers)
  • Login to docker hub and check. shouldn't find images with for webapp_demo
  • Execute Jenkins job
  • Check images in Docker hub. Now you could able to see new images pushed to mkn400 Docker_Hub

Troubleshooting:

• Docker should be installed on ansible server
• Should login to "docker hub" on ansible server
• dockeradmin user should be part of docker group

In next step we create create_docker_container.yml playbook. this get intiated by jenkins job, run by ansible and exected on dokcer host

Deploy Containers

• Write a yml file to create a container (file name : create_docker_container.yml) on /opt/playbooks

mkdir /opt/playbooks
cd /opt/playbooks
vi create_docker_container.yml

---
  - hosts: web-servers
    become: true
    tasks:
     - name: stop previous version docker
       shell: docker stop webapp_demo
     - name: remove stopped container
       shell: docker rm -f webapp_demo	  
     - name: remove docker images
       shell: docker image rm -f mkn400/webapp_demo
     - name: create docker image
       shell: docker run -d --name webapp_demo -p 8090:8080 mkn400/webapp_demo

• Add this script to Jenkins job.

  • Chose "configure" to modify your jenkins job.
    • Under post build actions
      • Send files or execute commands over SSH
        • Exec Command:

        cd /opt/playbooks
        ansible-playbook create_docker_container.yml

• Execute Jenkins job.

• You could see a new container on your docker host. can able access it from browser on port 8090

❗ Makesure you have opened required ports on AWS Security group for this server. ❗

Deploy with Version Control Containers

So for we used latest docker image to build a container, but what happens if latest version is not working? One easiest solution is, maintaining version for each build. This can be achieved by using environment variables.

Here we use a variables called BUILD_ID - The current build id of the job. For more info kindly click here

All are same as Create an docker image above. but change Send files or execute commands over SSH section as follows.

• Send files or execute commands over SSH
  • Name: ansible_server
  • Source files : Dockerfile
  • Remote directory : //opt//docker
  • Exec Command:

    cd /opt/docker
    docker build -t webapp_demo:v1.$BUILD_ID .
    docker tag webapp_demo:v1.$BUILD_ID mkn400/webapp_demo:v1.$BUILD_ID
    docker tag webapp_demo:v1.$BUILD_ID mkn400/webapp_demo:latest
    docker push mkn400/webapp_demo:v1.$BUILD_ID
    docker push mkn400/webapp_demo:latest
    docker rmi webapp_demo:v1.$BUILD_ID mkn400/webapp_demo:v1.$BUILD_ID
    mkn400/webapp_demo:latest

I'm Happy To Get Suggestions 😄