Hi Alex, My opinion is as follows: When log-slave-updates is not set, the slave is not binlogging the updates it is applying, so the comments do not go to the binary log either. When log-slave-updates is set, the action should depend on the binlog-annotate-row-events setting, like it's done on the master. That is, if binlog-annotate-row-events is on, annotate events should be passed to slave's binary log, otherwise they should be discarded. There is one hole left: if one does mysqlbinlog /path/to/binlog | mysql --host=slave-which-has-log-slave-updates then the annotations will not make it to slave's binary log. I think that should be ok, but we better get a confirmation of this to be sure. One should also take care that the slave do not write annotations for SQL statements in form of BINLOG 'xaqw324435324hnjsfp' as they are not useful (or at least don't copy the entire 'xaqe23....' part). BR Sergey -- Sergey Petrunia, Software Developer Monty Program AB, http://askmonty.org Blog: http://s.petrunia.net/blog