You can lock yourself out of maxadmin

[markusjm@localhost build-develop]$ bin/maxadmin list listeners

Listeners.

---------------------+---------------------+--------------------+-----------------+-------+--------

Name                 | Service Name        | Protocol Module    | Address         | Port  | State

---------------------+---------------------+--------------------+-----------------+-------+--------

RW-Split-Listener    | RW-Split-Router     | MariaDBClient      | *               |  4006 | Running

SchemaRouter-Listener | SchemaRouter-Router | MariaDBClient      | *               |  4010 | Running

RW-Split-Hint-Listener | RW-Split-Hint-Router | MariaDBClient      | *               |  4009 | Running

Read-Connection-Listener | Read-Connection-Router | MariaDBClient      | *               |  4008 | Running

CLI-Listener         | CLI                 | maxscaled          | default         |     0 | Running

---------------------+---------------------+--------------------+-----------------+-------+--------

[markusjm@localhost build-develop]$ bin/maxadmin shutdown service CLI

[markusjm@localhost build-develop]$ bin/maxadmin list listeners

^C