MySQL 8.0 Reference Manual Including MySQL NDB Cluster 8.0
MySQL 8.0 supports one status variable providing information about Group Replication. This variable is described here:
group_replication_primary_member
Shows the primary member's UUID when the group is operating in single-primary mode. If the group is operating in multi-primary mode, shows an empty string.
The group_replication_primary_member
status variable has been deprecated and is scheduled to be
removed in a future version.