To list the running services in your CentOS installation, there are several methods and tools that can be used. We suggest the following commands to meet this need:
Older versions of CentOS & Upstart:
List services and their open ports. This command can be important when you’re looking to do port forwarding or troubleshooting the network behavior of a unit:
Systemd(user & root), these commands can be used to list every service, including those that are inactive. This will also list a description of each service.
systemctl -l --type service --all
systemctl -r --type service --all