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Janak Shrestha
Janak Shrestha

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Deploy an App on Docker Containers

#docker

The Nautilus Application development team recently finished development of one of the apps that they want to deploy on a containerized platform. The Nautilus Application development and DevOps teams met to discuss some of the basic pre-requisites and requirements to complete the deployment. The team wants to test the deployment on one of the app servers before going live and set up a complete containerized stack using a docker compose fie. Below are the details of the task:

  1. On App Server 2 in Stratos Datacenter create a docker compose file /opt/sysops/docker-compose.yml (should be named exactly).
  2. The compose should deploy two services (web and DB), and each service should deploy a container as per details below:

For web service:

a. Container name must be php_host.

b. Use image php with any apache tag. Check here for more details.

c. Map php_host container's port 80 with host port 3000

d. Map php_host container's /var/www/html volume with host volume /var/www/html.

For DB service:

a. Container name must be mysql_host.

b. Use image mariadb with any tag (preferably latest). Check here for more details.

c. Map mysql_host container's port 3306 with host port 3306

d. Map mysql_host container's /var/lib/mysql volume with host volume /var/lib/mysql.

e. Set MYSQL_DATABASE=database_host and use any custom user ( except root ) with some complex password for DB connections.

  1. After running docker-compose up you can access the app with curl command curl <server-ip or hostname>:3000/

For more details check here.

Note: Once you click on FINISH button, all currently running/stopped containers will be destroyed and stack will be deployed again using your compose file.

Connect to App Server 2 

ssh steve@stapp02
sudo -i
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Password for steve: Am3ric@

Create the Compose Directory 

mkdir -p /opt/sysops
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Create the Docker Compose File 

vi /opt/sysops/docker-compose.yml
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Add the following content:

version: "3.8"

services:
  web:
    image: php:8.2-apache
    container_name: php_host
    ports:
      - "3000:80"
    volumes:
      - /var/www/html:/var/www/html
    depends_on:
      - db

  db:
    image: mariadb:latest
    container_name: mysql_host
    ports:
      - "3306:3306"
    volumes:
      - /var/lib/mysql:/var/lib/mysql
    environment:
      MYSQL_DATABASE: database_host
      MYSQL_USER: nautilus_user
      MYSQL_PASSWORD: S3cur3P@ssw0rd!
      MYSQL_ROOT_PASSWORD: R00tP@ssw0rd!
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Verify the Compose File 

cat /opt/sysops/docker-compose.yml
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Output:

version: "3.8"

services:
  web:
    image: php:8.2-apache
    container_name: php_host
    ports:
      - "3000:80"
    volumes:
      - /var/www/html:/var/www/html
    depends_on:
      - db

  db:
    image: mariadb:latest
    container_name: mysql_host
    ports:
      - "3306:3306"
    volumes:
      - /var/lib/mysql:/var/lib/mysql
    environment:
      MYSQL_DATABASE: database_host
      MYSQL_USER: nautilus_user
      MYSQL_PASSWORD: S3cur3P@ssw0rd!
      MYSQL_ROOT_PASSWORD: R00tP@ssw0rd!
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Validate the Compose Configuration 

cd /opt/sysops
docker compose config
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Output:

WARN[0000] /opt/sysops/docker-compose.yml: the attribute `version` is obsolete, it will be ignored, please remove it to avoid potential confusion 
name: sysops
services:
  db:
    container_name: mysql_host
    environment:
      MYSQL_DATABASE: database_host
      MYSQL_PASSWORD: S3cur3P@ssw0rd!
      MYSQL_ROOT_PASSWORD: R00tP@ssw0rd!
      MYSQL_USER: nautilus_user
    image: mariadb:latest
    networks:
      default: null
    ports:
      - mode: ingress
        target: 3306
        published: "3306"
        protocol: tcp
    volumes:
      - type: bind
        source: /var/lib/mysql
        target: /var/lib/mysql
        bind: {}
  web:
    container_name: php_host
    depends_on:
      db:
        condition: service_started
        required: true
    image: php:8.2-apache
    networks:
      default: null
    ports:
      - mode: ingress
        target: 80
        published: "3000"
        protocol: tcp
    volumes:
      - type: bind
        source: /var/www/html
        target: /var/www/html
        bind: {}
networks:
  default:
    name: sysops_default
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The configuration validates successfully. The version attribute warning is informational only and does not affect the deployment.

Deploy the Stack 

docker compose up -d
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Output:

WARN[0000] /opt/sysops/docker-compose.yml: the attribute `version` is obsolete, it will be ignored, please remove it to avoid potential confusion 
[+] up 29/29
 ✔ Image mariadb:latest   Pulled                                                                                          11.5s
 ✔ Image php:8.2-apache   Pulled                                                                                          13.5s
 ✔ Network sysops_default Created                                                                                         0.1s
 ✔ Container mysql_host   Created                                                                                         0.1s
 ✔ Container php_host     Created                                                                                         0.1s
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Both images were pulled, the network was created, and both containers were started.

Verify the Containers Are Running 

docker compose ps
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Output:

NAME         IMAGE            COMMAND                  SERVICE   CREATED         STATUS         PORTS
mysql_host   mariadb:latest   "docker-entrypoint.s…"   db        4 seconds ago   Up 2 seconds   0.0.0.0:3306->3306/tcp, [::]:3306->3306/tcp
php_host     php:8.2-apache   "docker-php-entrypoi…"   web       4 seconds ago   Up 2 seconds   0.0.0.0:3000->80/tcp, [::]:3000->80/tcp
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Both containers are running with the correct names and port mappings.

Test the Web Service 

curl -I http://localhost:3000/
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Output:

HTTP/1.1 200 OK
Date: Thu, 29 Oct 2026 08:57:43 GMT
Server: Apache/2.4.69 (Debian)
X-Powered-By: PHP/8.2.35
Content-Type: text/html; charset=UTF-8
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The HTTP 200 OK response confirms the PHP/Apache container is accessible on host port 3000 and running PHP 8.2.35.

Complete Command Sequence 

ssh steve@stapp02
sudo -i

mkdir -p /opt/sysops

cat > /opt/sysops/docker-compose.yml << 'EOF'
version: "3.8"

services:
  web:
    image: php:8.2-apache
    container_name: php_host
    ports:
      - "3000:80"
    volumes:
      - /var/www/html:/var/www/html
    depends_on:
      - db

  db:
    image: mariadb:latest
    container_name: mysql_host
    ports:
      - "3306:3306"
    volumes:
      - /var/lib/mysql:/var/lib/mysql
    environment:
      MYSQL_DATABASE: database_host
      MYSQL_USER: nautilus_user
      MYSQL_PASSWORD: S3cur3P@ssw0rd!
      MYSQL_ROOT_PASSWORD: R00tP@ssw0rd!
EOF

cd /opt/sysops
docker compose config
docker compose up -d
docker compose ps
curl -I http://localhost:3000/
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