Restart This Running MariaDB Galera Cluster

The MariaDB server needs to be stopped on all nodes:

sudo systemctl stop mariadb.service

The grastate.dat file needs to be examined on each node, to determine which is most advanced:

sudo cat /var/lib/mysql/grastate.dat

The following commands will be run only on the most advanced, node as determined in the previous step.

Edit node configuration in /etc/my.cnf.d/:

wsrep_cluster_address=gcomm://

Start the node:

sudo systemctl stop mariadb.service

Now we can connect to the server using using the mysql client on the node we bootstrapped in the previous step:

mysql

Once connected, we can run the following SQL statement to confirm the cluster is running:

SHOW GLOBAL STATUS WHERE Variable_name IN ('wsrep_ready', 'wsrep_cluster_size', 'wsrep_cluster_status', 'wsrep_connected');

A cluster size of 1 means only one node is connected.

To join the other node to the cluster, we need to edit its configuration in /etc/my.cnf.d/. Be certain to use the private IP of the already running node for the cluster address:

wsrep_cluster_address=gcom://10.0.1.110

Start the node:

sudo systemctl start mariadb.service