To check and list running services on Red Hat or CentOS, you can use the systemctl command. This command allows you to control the system service manager and manage services on your system.
To list all running services, use the list-units option and specify the --type option with a value of service:
systemctl list-units --type service
This will show a list of all services that are currently running on the system. The LOAD column indicates whether the service is loaded, and the ACTIVE column indicates whether the service is currently running.
To list only active services, you can use the --all option:
systemctl list-units --type service --all
You can also use the systemctl command to check the status of a specific service. For example, to check the status of the Apache HTTP server, you can use the following command:
systemctl status httpd
This will show the status of the Apache HTTP server, including whether it is running or stopped, and any error messages or other information about the service.
You can also use the systemctl command to start, stop, or restart a service. For example, to stop the Apache HTTP server, you can use the following command:
systemctl stop httpd
To start the Apache HTTP server, you can use the following command:
systemctl start httpd
And to restart the Apache HTTP server, you can use the following command:
systemctl restart httpd
Note that you may need to use sudo to run these commands, depending on your system configuration and your user permissions.