Stop and start HA configuration

Check Galera cluster leader 

To stop or start the Galera cluster you should first identify the leader node.

1. On the datanodes, check the state of Galera:

   [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: 0

   If 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).
   
   
   

Stop Galera cluster

To stop the Galera cluster do these steps.

1. Find the leader node as described above

2. Starting with the nodes that are not the leader. Stop the database on all nodes, .

   [root@datanodes2 /]# systemctl stop mariadb [root@datanodes1 /]# systemctl stop mariadb [root@datanodes0 /]# systemctl stop mariadb

   
   
   

Start Galera cluster

To start the Galera cluster, log in to the leader node.

1. Start the cluster with this command

   [root@datanodes0 /]# galera_new_cluster

   
   
   

2. On the other nodes, just start MariaDB or MySQL service

   
   
   

 You can use these commands to check the cluster status:

Check and rejoin RabbitMQ cluster

On each datanode server do these commands.

Start services and servers

After you restart the Galera, MySQL and RabbitMQ on the datanode servers, do these steps

1. On the services datanodes, manually start the Redis service

2. Start the monitoring cluster (remember to wait 5 minutes for Cassandra and 1 minute for KairosDB)

3. Start other Abiquo servers (or restart tomcat services)