when I tried to install RocketChat in Ubuntu 16.04
In Command Prompt I enter.
systemctl enable mongod
After That I got The issue.
systemctl: command not found
How to solve this?
sudo dpkg -l | grep systemd.
sudo apt-get install systemd. But if it does it might be damaged, so you may try to reinstall it
sudo apt-get install --reinstall systemd.
sudo dpkg -L systemd. Maybe binary files are located in a directory that is not included into $PATH variable.