MySQL Instance Manager is been deprecated in MySQL 5.1 and is removed in MySQL 5.5.
To monitor the status of each guarded server instance, the MySQL
Instance Manager attempts to connect to the instance at regular
intervals using the
MySQL_Instance_Manager@localhost user account
with a password of
You are not required to create this account for MySQL Server; in fact, it is expected that it will not exist. Instance Manager can tell that a server is operational if the server accepts the connection attempt but refuses access for the account by returning a login error. However, these failed connection attempts are logged by the server to its general query log (see Section 5.4.2, “The General Query Log”).
Instance Manager also attempts a connection to nonguarded server
instances when you use the
SHOW INSTANCES or
SHOW INSTANCE STATUS command. This is the
only status monitoring done for nonguarded instances.
Instance Manager knows if a server instance fails at startup because it receives a status from the attempt. For an instance that starts but later crashes, Instance Manager receives a signal because it is the parent process of the instance.