IT notes

Galera

To periodically check status of the cluster, create a script (/tmp/xx): #!/bin/sh mysql --defaults-file=/path/to/.my.cnf -s -e "SHOW GLOBAL STATUS WHERE Variable_name IN ('wsrep_ready', 'wsrep_cluster_size', 'wsrep_cluster_status', 'wsrep_connected');" And run it with: watch sh /tmp/xx If single node alive (ERROR 1047 WSREP has not yet prepared node for application use): SET GLOBAL wsrep_provider_options='pc.bootstrap=YES'; This node can be used now has the new master so others nodes can recover from it.