$ cat /etc/maxscale.cnf
[ReplicationMonitor]
type = monitor
module = mariadbmon
servers = worker_1, worker_2, worker_3

user = maxscale
password = ***

replication_user = rep
replication_password = ***

disk_space_threshold = /:90
disk_space_check_interval = 10000ms

backend_read_timeout = 6s
auto_failover = true
auto_rejoin = true
monitor_interval = 1000
failcount = 10
enforce_read_only_slaves = true
handle_events = false

[WritableService]
type = service
router = readconnroute
user = max
password = ***
router_options = master
servers = worker_1, worker_2, worker_3

[ReadOnlyService]
type = service
router = readconnroute
user = max
password = ***
router_options = slave
servers = worker_1, worker_2, worker_3

[WritableListener]
type = listener
service = WritableService
protocol = MariaDBClient
port = 3306

[ReadOnlyListener]
type = listener
service = ReadOnlyService
protocol = MariaDBClient
port = 3307