I have installed MaxScale 2.3.11 to Centos7, to near 50 servers.

Test scenario:
1) systemctl stop mariadb on Galera-node3
2) systemctl restart maxscale on proxy-node.

After restart, following is displayed on /var/log/maxscale/maxscale.log:

2019-08-23 14:48:58 notice : Loaded module MySQLAuth: V1.1.0 from /usr/lib64/maxscale/libmysqlauth.so
2019-08-23 14:48:58 notice : Loaded module MaxAdminAuth: V2.1.0 from /usr/lib64/maxscale/libmaxadminauth.so
2019-08-23 14:48:58 notice : Housekeeper thread started.
2019-08-23 14:48:58 notice : Using encrypted passwords. Encryption key: '/var/lib/maxscale/.secrets'.
2019-08-23 14:48:58 notice : Loaded server states from journal file: /var/lib/maxscale/MariaDB-Monitor/monitor.dat
2019-08-23 14:48:58 notice : Starting a total of 3 services...
2019-08-23 14:48:58 error : [Read-Only-Service] Failed to connect to server 'server3' ([galera3]:3306) when checking authentication user credentials and permissions: 2002 Can't connect to MySQL server on 'galera3' (115)
2019-08-23 14:48:58 error : Failure loading users data from backend [galera3:3306] for service [Read-Only-Service]. MySQL error 2002, Can't connect to MySQL server on 'galera3' (115)
2019-08-23 14:48:58 error : Unable to get user data from backend database for service [Read-Only-Service]. Failed to connect to any of the backend databases.
2019-08-23 14:48:58 error : [Read-Only-Service] Unable to load users for listener Read-Only-Listener listening at [/var/lib/maxscale/maxscale.sock]:0.
2019-08-23 14:48:58 notice : [Read-Only-Service] No users were loaded but 'inject_service_user' is enabled. Enabling service credentials for authentication until database users have been successfully loaded.
2019-08-23 14:48:58 notice : Listening for connections at [/var/lib/maxscale/maxscale.sock]:0 with protocol MySQL
2019-08-23 14:48:58 notice : Service 'Read-Only-Service' started (1/3)
2019-08-23 14:48:58 notice : [Read-Write-Service] Loaded 8 MySQL users for listener Read-Write-Listener from server server1.
2019-08-23 14:48:58 notice : Listening for connections at [/var/lib/maxscale/maxscale.sock]:0 with protocol MySQL
2019-08-23 14:48:58 notice : Service 'Read-Write-Service' started (2/3)
2019-08-23 14:48:58 notice : Listening for connections at [/var/run/maxscale/maxadmin.sock]:0 with protocol MaxScale Admin
2019-08-23 14:48:58 notice : Service 'MaxAdmin-Service' started (3/3)
2019-08-23 14:48:58 notice : Started REST API on [127.0.0.1]:8989
2019-08-23 14:48:58 notice : MaxScale started with 1 worker threads, each with a stack size of 8388608 bytes.
2019-08-23 14:48:58 error : Failure loading users data from backend [galera3:3306] for service [Read-Only-Service]. MySQL error 2002, Can't connect to MySQL server on 'galera3' (115)
2019-08-23 14:48:58 error : Unable to get user data from backend database for service [Read-Only-Service]. Failed to connect to any of the backend databases.
2019-08-23 14:48:58 error : [Read-Only-Service] Unable to load users for listener Read-Only-Listener listening at [/var/lib/maxscale/maxscale.sock]:0.
2019-08-23 14:48:58 notice : [Read-Only-Service] No users were loaded but 'inject_service_user' is enabled. Enabling service credentials for authentication until database users have been successfully loaded.

But command 'maxctrl list servers' shows stopped node as Running. If my memory is right, this was working correctly on previous version of MaxSale (2.3.9?)