After enabling detect_replication_lag, MariaDBMon does not create the maxscale_schema.replication_heartbeat database and table

#: changing configs

[root@box01 ~]# vi /var/lib/maxscale/maxscale.cnf.d/cluster-monitor.cnf

[root@box01 ~]# grep lag /var/lib/maxscale/maxscale.cnf.d/cluster-monitor.cnf

detect_replication_lag=true

#: logs

2018-01-15 16:56:32   notice : MaxScale started with 1 worker threads, each with a stack size of 8388608 bytes.

2018-01-15 16:56:32   info   : [qc_sqlite] In-memory sqlite database successfully opened for thread 139803373354112.

2018-01-15 16:56:32   error  : [mariadbmon] Error creating maxscale_schema.replication_heartbeat table in Master server: Unknown database 'maxscale_schema'

2018-01-15 16:56:32   error  : [mariadbmon] Error deleting from maxscale_schema.replication_heartbeat table: [DELETE FROM maxscale_schema.replication_heartbeat WHERE master_timestamp < 1515862592], Table 'maxscale_schema.replication_heartbeat' doesn't exist

2018-01-15 16:56:32   error  : [mariadbmon] Error updating maxscale_schema.replication_heartbeat table: [UPDATE maxscale_schema.replication_heartbeat SET master_timestamp = 1516035392 WHERE master_server_id = 2 AND maxscale_id = 0], Table 'maxscale_schema.replication_heartbeat' doesn't exist

2018-01-15 16:56:32   error  : [mariadbmon] error: replication heartbeat: failed selecting from hearthbeat table of 192.168.50.13:3306 : [SELECT master_timestamp FROM maxscale_schema.replication_heartbeat WHERE maxscale_id = 0 AND master_server_id = 2], Table 'maxscale_schema.replication_heartbeat' doesn't exist

2018-01-15 16:56:33   error  : [mariadbmon] Error creating maxscale_schema.replication_heartbeat table in Master server: Unknown database 'maxscale_schema'

2018-01-15 16:56:33   error  : [mariadbmon] Error deleting from maxscale_schema.replication_heartbeat table: [DELETE FROM maxscale_schema.replication_heartbeat WHERE master_timestamp < 1515862593], Table 'maxscale_schema.replication_heartbeat' doesn't exist

#: current monitor user's grants

MariaDB [(none)]> show grants for maxuser@'192.168.50.11'\G

*************************** 1. row ***************************

Grants for maxuser@192.168.50.11: GRANT ALL PRIVILEGES ON *.* TO 'maxuser'@'192.168.50.11' IDENTIFIED BY PASSWORD '*6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9'

1 row in set (0.00 sec)