Uploaded image for project: 'Percona Server'
  1. Percona Server
  2. PS-1119

LP #1722789: Intermediary slave does not log master changes with binlog_rows_query_log_events



      **Reported in Launchpad by Sveta Smirnova last update 20-12-2017 09:50:49

      Common scenario to reduce IO load on master is to create intermediary slave which uses BLACKHOLE storage engine, specify option log-slave-updates for it and replicate from this intermediary slave to multiple slaves with data.

      However, if configuration file on master has option binlog_rows_query_log_events=1 only INSERT statements will be recorded in the binary log of the intermediary slave.

      According to the user manual at https://dev.mysql.com/doc/refman/5.7/en/replication-options-binary-log.html#sysvar_binlog_... "The binlog_rows_query_log_events system variable affects row-based logging only. When enabled, it causes the MySQL Server to write informational log events such as row query log events into its binary log. This information can be used for debugging and related purposes; such as obtaining the original query issued on the master when it cannot be reconstructed from the row updates. " It does not say this option should be used for anything, but debugging purpose, therefore I do not see any reason why slave updates are not logged on server B.

      How to repeat:
      Setup replication chain: A -> B -> C

      Create InnoDB table on A.
      Convert InnoDB table to Blackhole on B.
      Same table on C continue using InnoDB storage engine.

      Now modify content on A. INSERT will be recorded correctly, UPDATE and DELETE will be recorded on master, but not on B even if it has option log-slave-updates

      I will also attach test case for MTR.





              • Assignee:
                lpjirasync lpjirasync
              • Votes:
                0 Vote for this issue
                1 Start watching this issue


                • Created: