------------------------|---------------------------------------------------------------
mysql_hostname | **Optional.** Host name, IP Address, or unix socket (must be an absolute path).
mysql_port | **Optional.** Port number (default: 3306).
+mysql_socket | **Optional.** Use the specified socket (has no effect if `mysql_hostname` is used).
mysql_ignore_auth | **Optional.** Ignore authentication failure and check for mysql connectivity only.
mysql_database | **Optional.** Check database with indicated name.
mysql_file | **Optional.** Read from the specified client options file.