In this activity you are working as a DBA and have been tasked with recovering a crashed MariaDB Galera cluster.
Learning Objectives
Successfully complete this lab by achieving the following learning objectives:
- Determine the Most Advanced Node
We can check the sequence number of the node:
sudo -u mysql mysqld --wsrep_recover
Run this on all nodes, and the highest sequence number is the most advanced node.
- Bootstrap the Most Advanced Node
Edit the node configuration in
/etc/my.cnf.d/
:wsrep_cluster_address=gcomm://
Start the node:
sudo systemctl start mariadb.service
- Check Status and Add Nodes to the Cluster
Connect with
mysql
client and query status variables:SHOW GLOBAL STATUS WHERE Variable_name IN ('wsrep_ready', 'wsrep_cluster_size', 'wsrep_cluster_status', 'wsrep_connected');
Edit the node configuration in
/etc/my.cnf.d/
. Be certain to use the private IP of the running node:wsrep_cluster_address=gcom://10.0.0.110
Start the node:
sudo systemctl start mariadb.service