16.2.3.2 Compatibility with Previous Replication Statements
When a replica has multiple channels and a FOR CHANNEL
option is not specified, a valid statement generally acts on all available channels, with some specific exceptions. channel
For example, the following statements behave as expected for all except certain Group Replication channels:
START SLAVE
starts replication threads for all channels, except thegroup_replication_recovery
andgroup_replication_applier
channels.STOP SLAVE
stops replication threads for all channels, except thegroup_replication_recovery
andgroup_replication_applier
channels.SHOW SLAVE STATUS
reports the status for all channels, except thegroup_replication_applier
channel.FLUSH RELAY LOGS
flushes the relay logs for all channels, except thegroup_replication_applier
channel.RESET SLAVE
resets all channels.
Use 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 FOR CHANNEL
option is not used to specify which channel to act on: channel
Note that a default channel always exists in a single source replication topology, where statements and functions behave as in previous versions of MySQL.