RESET SLAVE [ALL]
RESET SLAVE makes the slave
forget its replication position in the master's binary log. This
statement is meant to be used for a clean start: It clears the
master info and relay log info repositories, deletes all the
relay log files, and starts a new relay log file. It also resets
to 0 the replication delay specified with the
MASTER_DELAY option to CHANGE MASTER
TO. RESET SLAVE does
not change the values of gtid_executed or
gtid_purged. To use
RESET SLAVE, the slave
replication threads must be stopped, so on a running slave use
STOP SLAVE before issuing
RESET SLAVE.
All relay log files are deleted, even if they have not been
completely executed by the slave SQL thread. (This is a
condition likely to exist on a replication slave if you have
issued a STOP SLAVE statement
or if the slave is highly loaded.)
In MySQL 5.6 (unlike the case in MySQL 5.1 and
earlier), RESET SLAVE does not
change any replication connection parameters such as master
host, master port, master user, or master password, which are
retained in memory. This means that START
SLAVE can be issued without requiring a
CHANGE MASTER TO statement
following RESET SLAVE.
Connection parameters are reset if the slave
mysqld is shut down following RESET
SLAVE. In MySQL 5.6.3 and later, you can instead use
RESET SLAVE ALL to reset these connection
parameters (Bug #11809016).
RESET SLAVE ALL does not clear the
IGNORE_SERVER_IDS list set by
CHANGE MASTER TO. This issue is
fixed in MySQL 5.7. (Bug #18816897)
In MySQL 5.6.7 and later, RESET SLAVE causes
an implicit commit of an ongoing transaction. See
Section 13.3.3, “Statements That Cause an Implicit Commit”.
If the slave SQL thread was in the middle of replicating
temporary tables when it was stopped, and
RESET SLAVE is issued, these
replicated temporary tables are deleted on the slave.
When used on a MySQL Cluster replication slave SQL node,
RESET SLAVE clears the
mysql.ndb_apply_status table. You should
keep in mind when using this statement that
ndb_apply_status uses the
NDB storage engine and so is
shared by all SQL nodes attached to the slave cluster.
Beginning with MySQL Cluster NDB 7.4.9, you can override this
behavior by issuing
SET
GLOBAL
@@ndb_clear_apply_status=OFF
prior to executing RESET SLAVE, which keeps
the slave from purging the ndb_apply_status
table in such cases.