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•Using SHOW REPLICA | SLAVE STATUS FOR CHANNEL channel . By default, if the FOR CHANNEL channel  clause is not used, this statement shows the replica status for all channels with one row per channel. The identifier Channel_name  is added as a column in the result set. If a FOR CHANNEL channel  clause is provided, the results show the status of only the named replication channel. 

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## Note 

The SHOW VARIABLES  statement does not work with multiple replication channels. The information that was available through these variables has been migrated to the replication performance tables. Using a SHOW VARIABLES  statement in a topology with multiple channels shows the status of only the default channel. 

The error codes and messages that are issued when multi-source replication is enabled specify the channel that generated the error. 

## Monitoring Channels Using Performance Schema Tables 

This section explains how to use the replication Performance Schema tables to monitor channels. You can choose to monitor all channels, or a subset of the existing channels. 

To monitor the connection status of all channels: 

mysql> SELECT * FROM replication_connection_status\G; *************************** 1. row *************************** CHANNEL_NAME: source_1 GROUP_NAME: SOURCE_UUID: 046e41f8-a223-11e4-a975-0811960cc264 THREAD_ID: 24 SERVICE_STATE: ON COUNT_RECEIVED_HEARTBEATS: 0 LAST_HEARTBEAT_TIMESTAMP: 0000-00-00 00:00:00 RECEIVED_TRANSACTION_SET: 046e41f8-a223-11e4-a975-0811960cc264:4-37 LAST_ERROR_NUMBER: 0 LAST_ERROR_MESSAGE: LAST_ERROR_TIMESTAMP: 0000-00-00 00:00:00 *************************** 2. row *************************** CHANNEL_NAME: source_2 GROUP_NAME: SOURCE_UUID: 7475e474-a223-11e4-a978-0811960cc264 THREAD_ID: 26 SERVICE_STATE: ON COUNT_RECEIVED_HEARTBEATS: 0 LAST_HEARTBEAT_TIMESTAMP: 0000-00-00 00:00:00 RECEIVED_TRANSACTION_SET: 7475e474-a223-11e4-a978-0811960cc264:4-6 LAST_ERROR_NUMBER: 0 LAST_ERROR_MESSAGE: LAST_ERROR_TIMESTAMP: 0000-00-00 00:00:00 2 rows in set (0.00 sec) 

In the above output there are two channels enabled, and as shown by the CHANNEL_NAME  field they are called source_1  and source_2 . 

The addition of the CHANNEL_NAME  field enables you to query the Performance Schema tables for a specific channel. To monitor the connection status of a named channel, use a WHERE CHANNEL_NAME= channel  clause: 

mysql> SELECT * FROM replication_connection_status WHERE CHANNEL_NAME=’source_1’\G *************************** 1. row *************************** CHANNEL_NAME: source_1 GROUP_NAME: SOURCE_UUID: 046e41f8-a223-11e4-a975-0811960cc264 

