[ReadWrite Split Router]
 type=service
 router=readwritesplit
 servers=backend1, [...]
 user=maxscale
 passwd=geheim
 max_slave_connections=100%
 max_slave_replication_lag=21

 [ReadWrite Split Listener]
 type=listener
 service=ReadWrite Split Router
 protocol=MySQLClient
 port=3306
 address=10.42.0.1