MySQL High Availability- P9: A lot of research has been done on replication, but most of the resulting concepts are never put into production. In contrast, MySQL replication is widely deployed but has never been adequately explained. This book changes that. Things are explained here that were previously limited to people willing to read a lot of source code and spend a lot of time debugging it in production, including a few late-night sessions. | Administrator. We will look at the MySQL Administrator in Replication Monitoring with MySQL Administrator on page 381. Monitoring Commands for the Slave The SHOW SLAVE STATUS command displays information about the slave s binary log its connection to the server and replication activity including the name and offset position of the current binlog file. This information is vital in diagnosing slave performance as we have seen in previous chapters. Example 10-5 shows the result of a typical SHOW SLAVE STATUS command executed on a server running MySQL version . Example 10-5. The SHOW SLAVE STATUS command mysql SHOW SLAVE STATUS G 1. row Slave_IO_State Waiting for master to send event Master_Host localhost Master_User rpl Master_Port 3306 Connect_Retry 60 Master_Log_File Read_Master_Log_Pos 39016226 Relay_Log_File Relay_Log_Pos 9353715 Relay_Master_Log_File Slave_IO_Running Yes Slave_SQL_Running Yes Replicate_Do_DB Replicate_Ignore_DB Replicate_Do_Table Replicate_Ignore_Table Replicate_Wild_Do_Table Replicate_Wild_Ignore_Table Last_Errno 0 Last_Error Skip_Counter 0 Exec_Master_Log_Pos 25263417 Relay_Log_Space 39016668 Until_Condition None Until_Log_File Until_Log_Pos 0 Master_SSL_Allowed No Master_SSL_CA_File Master_SSL_CA_Path Master_SSL_Cert Master_SSL_Cipher Master_SSL_Key Seconds_Behind_Master 66 Master_SSL_Verify_Server_Cert No Last_IO_Errno 0 Last_IO_Error Last_SQL_Errno 0 Last_SQL_Error Monitoring Slaves 377 Please purchase PDF Split-Merge on to remove this watermark. Replicate_Ignore_Server_Ids Master_Server_Id 1 1 row in set sec There is a lot of information here. This command is the most important command for replication. It is a good idea to study the details of each item presented. Rather than listing the information item by item we present the information from the perspective of an administrator. That is the information is normally inspected with a specific goal in mind. Thus we .