When a replica has multiple channels and a
option is not
specified, a valid statement generally acts on all available
channels, with some specific exceptions.
For example, the following statements behave as expected for all except certain Group Replication channels:
START SLAVEstarts replication threads for all channels, except the
STOP SLAVEstops replication threads for all channels, except the
SHOW SLAVE STATUSreports the status for all channels, except the
FLUSH RELAY LOGSflushes the relay logs for all channels, except the
RESET SLAVEresets all channels.
RESET SLAVE with caution as this
statement deletes all existing channels, purges their relay log
files, and recreates only the default channel.
Some replication statements cannot operate on all channels. In
this case, error 1964 Multiple channels exist on the
slave. Please provide channel name as an argument. is
generated. The following statements and functions generate this
error when used in a multi-source replication topology and a
option is not used to specify which channel to act on:
Note that a default channel always exists in a single source replication topology, where statements and functions behave as in previous versions of MySQL.