How can I disable all user-installed services on boot by default?
Here is a scenario. I installed ssh server, and by default it is enabled on boot. I know it can be disabled on boot with systemctl command. But how can I default disable any such service(s) on boot? If I install postgresql, mariadb, or any other service, all are set to be enabled on boot by default. I want any of such services to be disabled on boot by default. So I can enable them on boot whenever required.
How can I achieve this? (Fedora, Arch by default have user-installed services disabled on boot by default)
For Ubuntu 16.04 (Xenial Xerus)
