How to restart a cluster
This guide explains how to restart a MariaDB cluster from the Hikube console, for example when an instance no longer behaves normally.
Prerequisites
- A MariaDB cluster with the status Ready in your project
- The right to edit this cluster
What happens during the restart
All instances of the cluster restart at once:
- the cluster is unreachable for a few seconds while the instances restart;
- open connections are closed and your applications must reconnect;
- data is kept.
Plan the restart in a maintenance window or outside peak hours, and check that your applications can reconnect automatically.
Steps
1. Open the cluster page
- Open DB & Messaging → MariaDB.
- Open the cluster.
2. Start the restart
- Click Restart, next to the Edit and Delete buttons.
- The "Restart
<name>?" window recalls the effect of the restart. Confirm with Restart.
The "Restart started" message confirms that the request was accepted. The restart continues in the background.
A cluster that is still being created has nothing to restart yet: the request is refused. Wait a few minutes after the cluster reaches the status Ready, while it finishes starting, then start the restart again.
Verification
The cluster status does not change during a restart: it keeps showing Ready. To confirm the restart, check how many seconds the instance has been running:
mysql -h <host> -P 3306 -u <user> -p -e "SHOW GLOBAL STATUS LIKE 'Uptime';"
A low value confirms that the instance has just restarted.
Further reading
- MariaDB concepts: replication and high availability
- Scale a cluster's resources