What is MariaDB?

MariaDB is a fast, reliable, scalable, and easy to use open-source relational database system. MariaDB Server is intended for mission-critical, heavy-load production systems as well as for embedding into mass-deployed software.

https://mariadb.com/

TLDR

docker run --name mariadb bitnami/mariadb

Docker Compose

mariadb:
  image: bitnami/mariadb

Get this image

The recommended way to get the Bitnami MariaDB Docker Image is to pull the prebuilt image from the Docker Hub Registry.

docker pull bitnami/mariadb:latest

To use a specific version, you can pull a versioned tag. You can view the list of available versions in the Docker Hub Registry.

docker pull bitnami/mariadb:[TAG]

If you wish, you can also build the image yourself.

git clone https://github.com/bitnami/bitnami-docker-mariadb.git
cd bitnami-docker-mariadb
docker build -t bitnami/mariadb .

Persisting your database

If you remove the container all your data will be lost, and the next time you run the image the database will be reinitialized. To avoid this loss of data, you should mount a volume that will persist even after the container is removed.

Note! If you have already started using your database, follow the steps on backing up and restoring to pull the data from your running container down to your host.

The MariaDB image exposes a volume at /bitnami/mariadb/data, you can mount a directory from your host to serve as the data store. If the directory you mount is empty, the database will be initialized.

Note

Persistent volumes cannot be shared across container instances.

docker run -v /path/to/data:/bitnami/mariadb/data bitnami/mariadb

or using Docker Compose:

mariadb:
  image: bitnami/mariadb
  volumes:
    - /path/to/data:/bitnami/mariadb/data

Linking

If you want to connect to your MariaDB server inside another container, you can use the linking system provided by Docker.

Connecting a MySQL client container to the MariaDB server container

Step 1: Run the MariaDB image with a specific name

The first step is to start our MariaDB server.

Docker's linking system uses container ids or names to reference containers. We can explicitly specify a name for our MariaDB server to make it easier to connect to other containers.

docker run --name mariadb bitnami/mariadb

Step 2: Run MariaDB as a MySQL client and link to our server

Now that we have our MariaDB server running, we can create another container that links to it by giving Docker the --link option. This option takes the id or name of the container we want to link it to as well as a hostname to use inside the container, separated by a colon. For example, to have our MariaDB server accessible in another container with server as it's hostname we would pass --link mariadb:server to the Docker run command.

The Bitnami MariaDB Docker Image also ships with a MySQL client, but by default it will start a server. To start the client instead, we can override the default command Docker runs by stating a different command to run after the image name.

docker run --rm -it --link mariadb:server bitnami/mariadb mysql -h server -u root

We started the MySQL client passing in the -h option that allows us to specify the hostname of the server, which we set to the hostname we created in the link.

Note! You can also run the MySQL client in the same container the server is running in using the Docker exec command.

docker exec -it mariadb mysql -u root

Linking with Docker Compose

Step 1: Add a MariaDB entry in your docker-compose.yml

Copy the snippet below into your docker-compose.yml to add MariaDB to your application.

mariadb:
  image: bitnami/mariadb

Step 2: Link it to another container in your application

Update the definitions for containers you want to access your MariaDB server from to include a link to the mariadb entry you added in Step 1.

myapp:
  image: myapp
  links:
    - mariadb:mariadb

Inside myapp, use mariadb as the hostname for the MariaDB server.

Configuration

Setting the root password on first run

Passing the MARIADB_PASSWORD environment variable when running the image for the first time will set the password of the root user to the value of MARIADB_PASSWORD.

docker run --name mariadb -e MARIADB_PASSWORD=password123 bitnami/mariadb

or using Docker Compose:

mariadb:
  image: bitnami/mariadb
  environment:
    - MARIADB_PASSWORD=password123

Creating a database on first run

By passing the MARIADB_DATABASE environment variable when running the image for the first time, a database will be created. This is useful if your application requires that a database already exists, saving you from having to manually create the database using the MySQL client.

docker run --name mariadb -e MARIADB_DATABASE=my_database bitnami/mariadb

or using Docker Compose:

mariadb:
  image: bitnami/mariadb
  environment:
    - MARIADB_DATABASE=my_database

Creating a database user on first run

You can create a restricted database user that only has permissions for the database created with the MARIADB_DATABASE environment variable. To do this, provide the MARIADB_USER environment variable.

Warning! In this case, a root user will not be created, and your restricted user will not have permissions to create a new database.

docker run --name mariadb -e MARIADB_USER=my_user -e MARIADB_DATABASE=my_database bitnami/mariadb

or using Docker Compose:

mariadb:
  image: bitnami/mariadb
  environment:
    - MARIADB_USER=my_user
    - MARIADB_DATABASE=my_database

Note! When MARIADB_PASSWORD is specified along with MARIADB_USER, the value specified in MARIADB_PASSWORD is set as the password of the newly created user specified in MARIADB_USER.

Setting up a replication cluster

A zero downtime MariaDB master-slave replication cluster can easily be setup with the Bitnami MariaDB Docker Image using the following environment variables:

• MARIADB_SERVER_ID: Unique server identifier (default: random number)
• MARIADB_REPLICATION_MODE: Replication mode. Possible values master/slave (default: none).
• MARIADB_REPLICATION_USER: Replication user. User is created on master on the first boot (default: none).
• MARIADB_REPLICATION_PASSWORD: Replication users password. Password is set for MARIADB_REPLICATION_USER on master on the first boot (default: none).
• MARIADB_MASTER_HOST: Hostname/IP of replication master (parameter available only on slave).
• MARIADB_MASTER_USER: User on replication master with access to MARIADB_DATABASE (parameter available only on slave).
• MARIADB_MASTER_PASSWORD: Password of user on replication master with access to MARIADB_DATABASE (parameter available only on slave).

In a replication cluster you can have one master and zero or more slaves. With replication writes can occur only on the master while reads can take place on both the master or slaves. For best performance you should limit the reads to the slaves and use the master only for the writes.

Step 1: Create the replication master

The first step is to start the MariaDB master.

docker run --name mariadb-master \
  -e MARIADB_SERVER_ID=1 \
  -e MARIADB_USER=my_user \
  -e MARIADB_PASSWORD=my_password \
  -e MARIADB_DATABASE=my_database \
  -e MARIADB_REPLICATION_MODE=master \
  -e MARIADB_REPLICATION_USER=my_repl_user \
  -e MARIADB_REPLICATION_PASSWORD=my_repl_password \
  bitnami/mariadb

In this command we are configuring the container as the master using the MARIADB_REPLICATION_MODE=master parameter. Using the MARIADB_REPLICATION_USER and MARIADB_REPLICATION_PASSWORD parameters we are creating a replication user that will be used by the slaves to connect to the master and perform the replication.

Step 2: Create the replication slave

Next we start a MariaDB slave container.

docker run --name mariadb-slave --link mariadb-master:master \
  -e MARIADB_SERVER_ID=2 \
  -e MARIADB_USER=my_user \
  -e MARIADB_PASSWORD=my_password \
  -e MARIADB_DATABASE=my_database \
  -e MARIADB_REPLICATION_MODE=slave \
  -e MARIADB_REPLICATION_USER=my_repl_user \
  -e MARIADB_REPLICATION_PASSWORD=my_repl_password \
  -e MARIADB_MASTER_HOST=mariadb-master -e MARIADB_MASTER_USER=my_user -e MARIADB_MASTER_PASSWORD=my_password \
  bitnami/mariadb

In this command we are configuring the container as a slave using the MARIADB_REPLICATION_MODE=slave parameter. Before the replication slave is started, the MARIADB_MASTER_HOST, MARIADB_MASTER_USER and MARIADB_MASTER_PASSWORD parameters are used by the slave container to connect to the master and take a dump of the existing data in the database identified by the MARIADB_DATABASE paramater. The MARIADB_REPLICATION_USER and MARIADB_REPLICATION_PASSWORD credentials are used to read the binary replication logs from the master.

Using the master docker link alias, the Bitnami MariaDB Docker image automatically fetches the replication paramaters from the master container, namely:

• MARIADB_REPLICATION_USER
• MARIADB_REPLICATION_PASSWORD
• MARIADB_MASTER_HOST
• MARIADB_MASTER_USER
• MARIADB_MASTER_PASSWORD

Additionally, the following parameters are also fetched in the slave container:

• MARIADB_USER
• MARIADB_PASSWORD
• MARIADB_DATABASE

As a result you can drop all of these parameters from the slave. Since MARIADB_SERVER_ID is assigned a random identifier we can drop it as well:

docker run --name mariadb-slave --link mariadb-master:master \
  -e MARIADB_REPLICATION_MODE=slave \
  bitnami/mariadb

With these two commands you now have a two node MariaDB master-slave replication cluster up and running. When required you can add more slaves to the cluster without any downtime allowing you to scale the cluster horizontally.

Note:

The cluster only replicates the database specified in the MARIADB_DATABASE parameter.

With Docker Compose the master-slave replication can be setup using:

master:
  image: bitnami/mariadb
  environment:
    - MARIADB_USER=my_user
    - MARIADB_PASSWORD=my_password
    - MARIADB_DATABASE=my_database
    - MARIADB_REPLICATION_MODE=master
    - MARIADB_REPLICATION_USER=my_repl_user
    - MARIADB_REPLICATION_PASSWORD=my_repl_password

slave:
  image: bitnami/mariadb
  links:
    - master:master
  environment:
    - MARIADB_REPLICATION_MODE=slave

Scale the number of slaves using:

docker-compose scale master=1 slave=3

The above command scales up the number of slaves to 3. You can scale down in the same way.

Note: You should not scale up/down the number of master nodes. Always have only one master node running.

Command-line options

The simplest way to configure your MariaDB server is to pass custom command-line options when running the image.

docker run bitnami/mariadb --open-files-limit=2

or using Docker Compose:

mariadb:
  image: bitnami/mariadb
  command: --open-files-limit=2

Further Reading:

• MySQL Server Command Options
• Caveats

Configuration file

This image looks for configuration in /bitnami/mariadb/conf. You can mount a volume there with your own configuration, or the default configuration will be copied to your volume if it is empty.

Step 1: Run the MariaDB image

Run the MariaDB image, mounting a directory from your host.

docker run --name mariadb -v /path/to/mariadb/conf:/bitnami/mariadb/conf bitnami/mariadb

or using Docker Compose:

mariadb:
  image: bitnami/mariadb
  volumes:
    - /path/to/mariadb/conf:/bitnami/mariadb/conf

Step 2: Edit the configuration

Edit the configuration on your host using your favorite editor.

vi /path/to/mariadb/conf/my.cnf

Step 3: Restart MariaDB

After changing the configuration, restart your MariaDB container for changes to take effect.

docker restart mariadb

or using Docker Compose:

docker-compose restart mariadb

Further Reading:

• Server Option and Variable Reference
• Caveats

Caveats

The following options cannot be modified, to ensure that the image runs correctly.

--defaults-file=/opt/bitnami/mysql/my.cnf
--log-error=/opt/bitnami/mysql/logs/mysqld.log
--basedir=/opt/bitnami/mysql
--datadir=/opt/bitnami/mysql/data
--plugin-dir=/opt/bitnami/mysql/lib/plugin
--user=mysql
--socket=/opt/bitnami/mysql/tmp/mysql.sock

Logging

The Bitnami MariaDB Docker Image supports two different logging modes: logging to stdout, and logging to a file.

Logging to stdout

The default behavior is to log to stdout, as Docker expects. These will be collected by Docker, converted to JSON and stored in the host, to be accessible via the docker logs command.

docker logs mariadb

or using Docker Compose:

docker-compose logs mariadb

This method of logging has the downside of not being easy to manage. Without an easy way to rotate logs, they could grow exponentially and take up large amounts of disk space on your host.

Logging to file

To log to file, run the MariaDB image, mounting a directory from your host at /bitnami/mariadb/logs. This will instruct the container to send logs to a mysqld.log file in the mounted volume.

docker run --name mariadb -v /path/to/mariadb/logs:/bitnami/mariadb/logs bitnami/mariadb

or using Docker Compose:

mariadb:
  image: bitnami/mariadb
  volumes:
    - /path/to/mariadb/logs:/bitnami/mariadb/logs

To perform operations (e.g. logrotate) on the logs, mount the same directory in a container designed to operate on log files, such as logstash.

Maintenance

Backing up your container

To backup your data, configuration and logs, follow these simple steps:

Step 1: Stop the currently running container

docker stop mariadb

or using Docker Compose:

docker-compose stop mariadb

Step 2: Run the backup command

We need to mount two volumes in a container we will use to create the backup: a directory on your host to store the backup in, and the volumes from the container we just stopped so we can access the data.

docker run --rm -v /path/to/backups:/backups --volumes-from mariadb busybox \
  cp -a /bitnami/mariadb /backups/latest

or using Docker Compose:

docker run --rm -v /path/to/backups:/backups --volumes-from `docker-compose ps -q mariadb` busybox \
  cp -a /bitnami/mariadb /backups/latest

Note! If you only need to backup database data, or configuration, you can change the first argument to cp to /bitnami/mariadb/data or /bitnami/mariadb/conf respectively.

Restoring a backup

Restoring a backup is as simple as mounting the backup as volumes in the container.

docker run -v /path/to/backups/latest/data:/bitnami/mariadb/data \
  -v /path/to/backups/latest/conf:/bitnami/mariadb/conf \
  -v /path/to/backups/latest/logs:/bitnami/mariadb/logs \
  bitnami/mariadb

or using Docker Compose:

mariadb:
  image: bitnami/mariadb
  volumes:
    - /path/to/backups/latest/data:/bitnami/mariadb/data
    - /path/to/backups/latest/conf:/bitnami/mariadb/conf
    - /path/to/backups/latest/logs:/bitnami/mariadb/logs

Upgrade this image

Bitnami provides up-to-date versions of MariaDB, including security patches, soon after they are made upstream. We recommend that you follow these steps to upgrade your container.

Step 1: Get the updated image

docker pull bitnami/mariadb:latest

or if you're using Docker Compose, update the value of the image property to bitnami/mariadb:latest.

Step 2: Stop and backup the currently running container

Before continuing, you should backup your container's data, configuration and logs.

Follow the steps on creating a backup.

Step 3: Remove the currently running container

docker rm -v mariadb

or using Docker Compose:

docker-compose rm -v mariadb

Step 4: Run the new image

Re-create your container from the new image, restoring your backup if necessary.

docker run --name mariadb bitnami/mariadb:latest

or using Docker Compose:

docker-compose start mariadb

Testing

This image is tested for expected runtime behavior, using the Bats testing framework. You can run the tests on your machine using the bats command.

bats test.sh

Contributing

We'd love for you to contribute to this container. You can request new features by creating an issue, or submit a pull request with your contribution.

Issues

If you encountered a problem running this container, you can file an issue. For us to provide better support, be sure to include the following information in your issue:

• Host OS and version
• Docker version (docker version)
• Output of docker info
• Version of this container (echo $BITNAMI_APP_VERSION inside the container)
• The command you used to run the container, and any relevant output you saw (masking any sensitive information)

License

Copyright 2015 Bitnami

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.