The simplest way to check whether a Linux system is running systemd, upstart or SysV is by running the following command.
ps -p1 | grep "init\|upstart\|systemd"
References
How to determine which system manager is running on Linux System
The simplest way to check whether a Linux system is running systemd, upstart or SysV is by running the following command.
ps -p1 | grep "init\|upstart\|systemd"
How to determine which system manager is running on Linux System