How to restart MariaDB Galera cluster
If you need to restart the entire cluster, you must start from the last node that was down To restart the MariaDB Galera cluster follow the steps below:
- Identify which node has the most advanced node state ID.
- Start the most advanced node first.
- Start the rest of the nodes.
Identifying the most advanced node
To identify which node has the most advanced node state ID ( seqno) open the following file in each node: /opt/bitnami/grastate.dat. Then check the safe_to_bootstrap value. In case that this value is equal to 1, this is the node from which you can restart the cluster again.
Identifying crashed nodes
If the safe_to_bootstrap value is equal to -1, this is a crashed node. In the event that all the nodes are crashed, you will need to perform a database restoration.