Ansible-MariaDB-Cluster

Ansible playbook that provisions a group of servers to run mariadb as a Galera Cluster.

Requirements

If you are using HaProxy as a front end to the cluster without SSL, you will need to create a user for the health checks to work properly. The user does not need to be able to access any databases, it just needs to be able to authenticate against the server.

CREATE USER 'haproxy_check'@'10.10.10.253' WITH MAX_QUERIES_PER_HOUR 1 MAX_UPDATES_PER_HOUR 0 MAX_STATEMENT_TIME 0.0000000001;

If you are using HaProxy as a front end to the cluster with SSL, use default tcp checks to validate the service is available as HaProxy does not support the SSL settings for mysql.

If this is the first install, the mariadb_cluster_bootstrap variable will need to be set to true to bootstrap the cluster.

Variables

Variable	Required	Default	Description
mariadb_cluster_wsrep_cluster_name	yes	my_wsrep_cluster	The wsrep cluster name that should be used for the galera cluster
mariadb_cluster_access_ip	no	""	If defined, the normal database port (3306) will only be accessible from the defined IP for use with a load balancer

Example

---
# file: hosts

mariadb_cluster:
  hosts:
    db01:
      ansible_host: 10.10.10.11
    db02:
      ansible_host: 10.10.10.12

  vars:
    mariadb_cluster_wsrep_cluster_name: "CustomCluster1"
    mariadb_cluster_access_ip: "10.10.10.253"
    ansible_user: ansible
    

Troubleshooting

You can view the status of the cluster by running the following command.

SHOW GLOBAL STATUS LIKE 'wsrep_%';
SHOW GLOBAL VARIABLES LIKE 'have_ssl';
SHOW SESSION STATUS LIKE 'Ssl_cipher';
SHOW GLOBAL VARIABLES LIKE 'require_secure_transport';

License

See LICENSE file for full license information.