Please note, by default replication checksums are enabled. However following variables can be used to enable/disable checksums with master/relay logs:
a) Binlog_checksum - Its a dynamic variable. The default value is CRC32. This variable causes the master to write a checksum for each event in the binary log
When enabled binary log provides the following information:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 | #130225 15:33:56 server id 1 end_log_pos 384 CRC32 0x280a5e52 Intvar SET INSERT_ID=1/*!*/; #130225 15:33:56 server id 1 end_log_pos 499 CRC32 0x37e25d0a Query thread_id=1 exec_time=0 error_code=0 use `test`/*!*/; SET TIMESTAMP=1361806436/*!*/; insert into t1 values (null, 'mysql 5.6') /*!*/; # at 499 #130225 15:33:56 server id 1 end_log_pos 530 CRC32 0xf56d77c4 Xid = 17 COMMIT/*!*/; DELIMITER ; # End of log file ROLLBACK /* added by mysqlbinlog */; /*!50003 SET COMPLETION_TYPE=@OLD_COMPLETION_TYPE*/; |
CRC32 0x280a5e52
b) slave_sql_verify_checksum: Its ENABLED by default. However, as per online docs (here), this option is disabled by default, so I take it as documentation bug. When this option is ENABLED, slave host would examine and verify checksums when reading the relay log.
show global variables like 'slave_sql_verify_checksum'; +---------------------------+-------+ | Variable_name | Value | +---------------------------+-------+ | slave_sql_verify_checksum | ON | +---------------------------+-------+ 1 row in set (0.00 sec)
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