As you know, MySQL Group Replication runs by default in single primary mode.
mysql2 mysql> show global variables like 'group_replication_single_primary_mode';
+---------------------------------------+-------+
| Variable_name | Value |
+---------------------------------------+-------+
| group_replication_single_primary_mode | ON |
+---------------------------------------+-------+
But how can we easily find which member of the group is the
Primary-Master ?
Of course you could check which one is not in
read_only:
mysql2 mysql> select @@read_only;
+-------------+
| @@read_only |
+-------------+
| 1 |
+-------------+
But then you need to perform this on all the nodes one by one
until you find the right one.
The primary …
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