CentOS7-services

# To see System V init scripts that are available on your system and the runlevels on which they start, use the chkconfig command as follows:
chkconfig --list
# To show all units installed on the CentOS /RHEL 7 systemd based system, along with their current states:
systemctl list-unit-files
systemctl list-unit-files | grep enabled
# service command – list running services
# The syntax is as follows for CentOS/RHEL 6.x and older (pre systemd):
service --status-all
service --status-all | more
service --status-all | grep ntpd
service --status-all | less
# Print the status of any service
# To print the status of apache (httpd) service:
service httpd status
# List all known services (configured via SysV)
chkconfig --list
# List service and their open ports
netstat -tulpn
# Turn on / off service
ntsysv
chkconfig service off
chkconfig service on
chkconfig httpd off
chkconfig ntpd on
# ntsysv is a simple interface for configuring runlevel services which are also configurable through chkconfig. By default, it configures the current runlevel. Just type ntsysv and select service you want to run.
# A note about RHEL/CentOS 7.x with systemd
# If you are using systemd based distro such as Fedora Linux v22/23/24 or RHEL/CentOS Linux 7.x+. Try the following command to list running services using the systemctl command. It control the systemd system and service manager.
# To list systemd services on CentOS/RHEL 7.x+ use
# The syntax is:
systemctl
systemctl | more
systemctl | grep httpd
systemctl list-units --type service
systemctl list-units --type mount
# To list all services:
systemctl list-unit-files
# To view processes associated with a particular service (cgroup), you can use the systemd-cgtop command. Like the top command, systemd-cgtop lists running processes based on their service:
systemd-cgtop
# To list SysV services only on CentOS/RHEL 7.x+ use (does not include native systemd services)
chkconfig --list