Prometheus
Datadog
New RelicDatabases
MySQL
Troubleshooting guide for MySQL alerting rules — connections, replication, InnoDB, and slow queries.
Alert runbooks (3)
criticalMySQL down
The mysqld_exporter reports mysql_up == 0. The MySQL instance is unreachable.
warningMySQL too many connections
Connection count exceeds 80% of max_connections. New connections may be refused with 'Too many connections'.
warningMySQL slow queries
The rate of slow queries (exceeding long_query_time) is elevated.