Description:
The documentation on https://dev.mysql.com/doc/refman/5.7/en/group-replication-replication-group-members.html shows that the replication_group_members table in performance_schema would show the MEMBER_ROLE and MEMBER_VERSION for MySQL 5.7
However this feature is currently not supported for MySQL 5.7.
How to repeat:
# mysql
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Your MySQL connection id is 35
Server version: 5.7.25-log MySQL Community Server (GPL)
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owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
mysql> SELECT * FROM performance_schema.replication_group_members;
+---------------------------+--------------------------------------+-------------+-------------+--------------+
| CHANNEL_NAME | MEMBER_ID | MEMBER_HOST | MEMBER_PORT | MEMBER_STATE |
+---------------------------+--------------------------------------+-------------+-------------+--------------+
| group_replication_applier | 3811bcf1-1e85-11e9-bcae-5254008481d5 | node2 | 3306 | ONLINE |
| group_replication_applier | 381400ec-1e85-11e9-b322-5254008481d5 | node1 | 3306 | ONLINE |
| group_replication_applier | 39380c64-1e85-11e9-b2d2-5254008481d5 | node3 | 3306 | ONLINE |
+---------------------------+--------------------------------------+-------------+-------------+--------------+
3 rows in set (0.00 sec)
Suggested fix:
It would be nice if this behaviour could be back-ported from 8.0 to 5.7 as this gives useful information for cluster monitoring.
If not possible, docs should be updated to reflect the correct output for 5.7
