List all running services
sudo service --status-all
To restart the WiFI service:
sudo ifdown --force wlan0
sudo ifup wlan0
To restart the Ethernet service:
sudo ifdown eth0
sudo ifdown --force eth0(if necessary)
sudo ifup eth0
sudo /etc/init.d/networking restart
To restart the FTP service:
sudo service vsftpd restart
To restart all Raspbian services:
sudo service networking restart
or
sudo systemctl daemon-reload