In general, for monitoring standard MySQL replication, it is common practice to check the Seconds_Behind_Master variable. There are cases, however, where the Seconds_Behind_Master can have a low number, but replication is in fact broken. For checking this more accurately, Percona has written a program called pt-heartbeat, which continuously inserts timestamped data into a single row … Continue reading Set up Percona pt-heartbeat for Monitoring of MySQL Replication… Read More