How to configure grafana to limit user logins

I want to limit the number of users that allowed to connect to the server at the same time. There can be many user profiles but only 5 can be logged into the system at a time. I hope you can understand my requirement. Please help.

Grafana version is : 5.4.3
OS is : RHEL

I have read this forum also : Can we restrict number user to login into grafana