MariaDB and phpMyAdmin - Docker Setup & Usage Guide

ℹ️ Introduction

This guide explains how to set up and access a MariaDB database with phpMyAdmin using Docker Compose.By default this container uses our default External Docker network settings, to make sure containers in this network can work together.

What’s in my network

It can be useful to know what container, IPv4 addresses and ports are used in a network For this we have a script that displays the information for you. it can be found in my Powershelll-Utilities repository here. Use the docker-netw-info directory to execute the script

⚡🏃‍♂️ Quick Setup

Make sure the external network exists (or create it)

 docker network create --subnet=172.40.0.0/24 dev1-net

Create and start the container

 docker compose -f compose.yaml up -d --build --force-recreate --remove-orphans

Verify Network

Verify that both containers are on the same network: docker network inspect dev1-net
Also the other containers in the network will be shown including details like Ip address
Check the IP address inside a container: hostname -I

▶️ Usage

Default Credentials

Database: docker
Username: docker
Password: docker
Port: 3306 (internal), 9004 (external)

Access phpMyAdmin

Access phpMyAdmin from the host system at:

 
http://localhost:9001/
# Login using the default credentials above.

Access the Database from a Another Container

When connecting other Docker containers to this MariaDB instance, configure your compose file with these environment variables:

The service name from the current compose file as the host environment variable (DB_HOST)
The internal port (3306) as the port environment variable (DB_PORT)
The MARIADB_USER value as the user environment variable (DB_USER)
The MARIADB_PASSWORD value as the password environment variable (DB_PASSWORD)
The MARIADB_DATABASE value as the database name environment variable (DB_NAME)

Example: Web Application Compose File

 
webapp:
  build: ./webapp
  depends_on:
    - mariadb
  environment:
    DB_HOST: mariadb
    DB_PORT: 3306        # Use the internal port (second value)
    DB_USER: docker
    DB_PASSWORD: docker
    DB_NAME: docker

Access via DNS Name (from within Docker)

 
$dsn = 'mysql:host=mariadb;port=3306;dbname=docker;charset=utf8mb4';
$db = new PDO($dsn, 'docker', 'docker');  // first 'docker' = user, second = password

Access from Host or External Machine

When connecting from the host system or another machine on the network:

 
DB_HOST=127.0.0.1   # Use host's IP address for external machines
DB_PORT=9004        # Use the external port (first value in ports mapping)
DB_USER=docker
DB_PASSWORD=docker
DB_NAME=docker

Docker Stack MariaDB - Supporting container

A Docker container for MariaDB