mariadb-galera

MariaDB Galera cluster dockerized environment

• MariaDB Galera - MariaDB Galera Cluster is a virtually synchronous multi-master cluster for MariaDB

Notes about environment

• the configuration of the cluster is not persistent. docker-entrypoint.sh creates the cluster each time the container starts
• the configuration of the running cluster can be fount inside the containers in /etc/mysql/mariadb.conf.d/10-galera.cnf (docker-compose exec mariadb_node01 cat "/etc/mysql/mariadb.conf.d/10-galera.cnf")
• MariaDB volumes persist until command docker-compose down -v is gived
• at first startup of the cluster or when all nodes are down set BOOTSTRAP=1 on one of the nodes (--wsrep-new-cluster)

Environment variables

• BOOTSTRAP: tells mariadb to start with --wsrep-new-cluster parameter
• CLUSTER_NAME: the name of the cluster
• CLUSTER_MEMBERS: comma separated list of cluster members (ip or fqdn)

Usage

Start che cluster:

docker-compose up -d

Stop one node:

docker-compose stop mariadb_node01

Stop all nodes:

docker-compose stop

To start the cluster again (whit all nodes down) run:

bash restart_cluster.sh

This will delete all containers but the volumes with MariaDB data still exist. Now set BOOTSTRAP=1 on one of the nodes and then start the cluster:

docker-compose up -d

Tear down and clean all:

docker-compose down -v