To see whether a keyring plugin is loaded, check the Information Schema PLUGINS table or use the SHOW PLUGINS statement (see Section 5.5.2, “Obtaining Server Plugin Information”). For example:

mysql> SELECT PLUGIN_NAME, PLUGIN_STATUS
       FROM INFORMATION_SCHEMA.PLUGINS
       WHERE PLUGIN_NAME LIKE 'keyring%';
+--------------+---------------+
| PLUGIN_NAME  | PLUGIN_STATUS |
+--------------+---------------+
| keyring_file | ACTIVE        |
+--------------+---------------+