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To stop or start the Galera cluster you should first identify the leader node.
On the datanodes, check the state of Galera:
Code Block [root@datanodes2 /]# cd /var/lib/mysql/ [root@datanodes2 mysql]# cat grastate.dat # GALERA saved state version: 2.1 uuid: c0e2c5f4-e045-11e9-988e-d6d16254ad99 seqno: -1 safe_to_bootstrap: 0If there is a node with safe_to_bootstrap=1, you should start the cluster on this node
If no node is marked as safe_to_bootstrap, force it (using the virtual IP).
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Stop Galera cluster
To stop the Galera cluster do these steps.
Find the leader node as described above
Starting with the nodes that are not the leader. Stop the database on all nodes, .
Code Block [root@datanodes2 /]# systemctl stop mariadb [root@datanodes1 /]# systemctl stop mariadb [root@datanodes0 /]# systemctl stop mariadb
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Start Galera cluster
To start the Galera cluster, log in to the leader node.
Start the cluster with this command
Code Block [root@datanodes0 /]# galera_new_clusterOn the other nodes, just start MariaDB or MySQL service
Code Block [root@datanodes1 /]# systemctl start mariadb [root@datanodes2 /]# systemctl start mariadb
You can use these commands to check the cluster status:
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After you restart the Galera, MySQL and RabbitMQ on the datanode servers, do these steps
On the services datanodes, manually start the Redis service
Start the monitoring cluster (remember to wait 5 minutes for Cassandra and 1 minute for KairosDB)
Start other Abiquo servers (or restart tomcat services)