File README.SUSE of Package xinetd

# Systemd

SUSE distributions uses systemd as a default init system. It provides a
xinetd-like capability called socket activation, where services are spawned once
underlying socket get an incoming connection.

It is highly recommended for you to rather stick to socket activation than
continuing with usage of xinetd service activation.

## Example of socket activation

The xinetd configuration for ftp daemon /etc/xinetd.d/ftp

  service ftp
  {
    socket_type = stream
    protocol = tcp
    wait = no
    user = root
    server = /usr/sbin/ftpd
  }

This is an equvalent socket unit

  ftp.socket

  [Unit]
  Description=FTP Server socket
  
  [Socket]
  ListenStream=21
  #service is spawned for each incoming connection in inetd-style
  #Accept=true
  
  # Those two lines will ensure the ftp.socket will be created on a system boot
  [Install]
  WantedBy=sockets.target

  ftpd.service

  [Unit]
  Description=FTP Server service
  
  [Service]
  ExecStart=/usr/bin/ftpd
  # not needed in case, .service and .socket units has the same name
  Sockets=ftp.socket
  
Then you need to enable socket
  # systemctl enable ftp.socket
Start it (will be done on next boot if enabled before)
  # systemctl start ftp.socket

And server can be started manually by
  # systemctl enable ftp.service

Status of .socket and .service can be checked using systemctl status ftp.(socket|service)

Please consult systemd.socket(5), systemd.exec(5), systemd.service(5) and
systemd.unit(5) for detailed information about all options provided by systemd.

Your SUSE Team