MASTERCLASS #TASK ON DOCKER

4 min readJul 10, 2021

TASK#2 BASED ON BOTH DOCKER SESSIONS HAPPENED ON 3RD AND 4TH JULY,2021.

#TASK2.1: The compose should deploy two services (web and DB), and each service should deploy a container as per details below:

For web service: — ->> php:rc-apache

a. Container name must be php_web.

b. Use image php with any apache tag. Check here for more details https://hub.docker.com/_/php?tab=tags.

c. Map php_web container’s port 80 with host port 6000 d. Map php_web container’s /var/www/html volume with host volume /var/www/html.

For DB service:

a. Container name must be mysql_web.

b. Use image mariadb with any tag (preferably latest). Check here for more details https://hub.docker.com/_/mariadb?tab=tags.

c. Map mysql_web container’s port 3306 with host port 3306

d. Map mysql_web container’s /var/lib/mysql volume with host volume /var/lib/mysql.

e. Set MYSQL_DATABASE=database_web and use any custom user ( except root ) with some complex password for DB connections. After running docker-compose up you can access the app with curl command curl <server-ip or hostname>:6000/

SOLUTION:

Step 1: Create a directory using “mkdir” command. Get into that directory using “cd” command.

Step 2: Create docker-compose.yml file using “vim” command. Edit the docker-compose file, first section to define will be the web portion of the stack and next section defines the database.

Step 3: Create a directory named “php” under the previous directory. Create index.php file php directory. Edit index.php and add credentials for mysql access.

Step 4: Create a Dockerfile using “vim” command. Edit that file put specific keywords that dictate how to build a specific image.

Step 5: Install Docker compose.

sudo curl -L "https://github.com/docker/compose/releases/download/1.29.2/docker-compose-$(uname -s)-$(uname -m)" -o /usr/local/bin/docker-compose

sudo chmod +x /usr/local/bin/docker-composedocker-compose --version

Step 6: Build Docker Container.

Step 7: Use “docker-compose up “ command to aggregate the output of each container.

Step 8:

Use “docker-compose stop” command to Stop the docker-compose.
Use “docker-compose up -d” command for Detached mode: Run containers in the background.

Step 9:

Use “docker-compose ps” which only shows running containers.
Use “curl 192.168.29.22:6000” server-id with 6000 port number.
It will show output as “Successfuly Connected to MYSQL”

#TASK2.2: Dockerfile

1) Webserver

2) This is coming from Docker — -> Content

3) CentOS

SOLUTION:

Step 1:

Create a new directory
Create index.html file with some html content “This is coming from Docker” using “vim” command.
Create a Dockerfile which includes specific keywords that dictate how to build a specific image.

Step 2:

Use “systemctl start docker” to start the Docker Service
Use “docker build -t webserver .” to create a Docker image from the definition contained in a Dockerfile.