Folks,

We need to include the use_sql_variables_in as one of the possible variables to be changed with the command alter service <service name> <variable name> <value>. It's not part of the list of variables and we can change that, as you can see below:

root@maxscale01:~# maxctrl alter service rwsplit-service use_sql_variables_in master

OK

root@maxscale01:~# maxctrl show service rwsplit-service | grep use_sql_variables_in

│                     │     "use_sql_variables_in": "master",                       │

root@maxscale01:~# maxscale --version

MaxScale 2.3.5

The link I'm following on the documentation is the below one:
https://mariadb.com/kb/en/mariadb-maxscale-23-maxctrl/#alter-service

Thanks.