man > systemd-socket-activate(1)

Socket activation for systemd services.

  • Activate a service when a specific socket is connected
    systemd-socket-activate {{path/to/socket.service}}
  • Activate multiple sockets for a service
    systemd-socket-activate {{path/to/socket1.service}} {{path/to/socket2.service}}
  • Pass environment variables to the service being activated
    {{SYSTEMD_SOCKET_ACTIVATION=1}} systemd-socket-activate {{path/to/socket.service}}
  • Activate a service along with a notification socket
    systemd-socket-activate {{path/to/socket.socket}} {{path/to/service.service}}
  • Activate a service with a specified port
    systemd-socket-activate {{path/to/socket.service}} {{-l|--listen}} {{8080}}
SYSTEMD-SOCKET-ACTIVATE(1)             systemd-socket-activate            SYSTEMD-SOCKET-ACTIVATE(1)

NAME
       systemd-socket-activate - Test socket activation of daemons

SYNOPSIS


       systemd-socket-activate [OPTIONS...] daemon [OPTIONS...]

DESCRIPTION
       systemd-socket-activate may be used to launch a socket-activated service program from the
       command line for testing purposes. It may also be used to launch individual instances of the
       service program per connection.

       The daemon to launch and its options should be specified after options intended for
       systemd-socket-activate.

       If the --inetd option is given, the socket file descriptor will be used as the standard input
       and output of the launched process. Otherwise, standard input and output will be inherited,
       and sockets will be passed through file descriptors 3 and higher. Sockets passed through
       $LISTEN_FDS to systemd-socket-activate will be passed through to the daemon, in the original
       positions. Other sockets specified with --listen= will use consecutive descriptors. By
       default, systemd-socket-activate listens on a stream socket, use --datagram and --seqpacket
       to listen on datagram or sequential packet sockets instead (see below).

OPTIONS
       -l address, --listen=address
           Listen on this address. Takes a string like "2000" or "127.0.0.1:2001".

           Added in version 230.

       -a, --accept
           Launch an instance of the service program for each connection and pass the connection
           socket.

           Added in version 230.

       -d, --datagram
           Listen on a datagram socket (SOCK_DGRAM), instead of a stream socket (SOCK_STREAM). May
           not be combined with --seqpacket.

           Added in version 230.

       --seqpacket
           Listen on a sequential packet socket (SOCK_SEQPACKET), instead of a stream socket
           (SOCK_STREAM). May not be combined with --datagram.

           Added in version 230.

       --inetd
           Use the inetd protocol for passing file descriptors, i.e. as standard input and standard
           output, instead of the new-style protocol for passing file descriptors using $LISTEN_FDS
           (see above).

           Added in version 230.

       -E VAR[=VALUE], --setenv=VAR[=VALUE]
           Add this variable to the environment of the launched process. If VAR is followed by "=",
           assume that it is a variable–value pair. Otherwise, obtain the value from the environment
           of systemd-socket-activate itself.

           Added in version 230.

       --fdname=NAME[:NAME...]
           Specify names for the file descriptors passed. This is equivalent to setting
           FileDescriptorName= in socket unit files, and enables use of sd_listen_fds_with_names(3).
           Multiple entries may be specifies using separate options or by separating names with
           colons (":") in one option. In case more names are given than descriptors, superfluous
           ones will be ignored. In case less names are given than descriptors, the remaining file
           descriptors will be unnamed.

           Added in version 230.

       -h, --help
           Print a short help text and exit.

       --version
           Print a short version string and exit.

ENVIRONMENT VARIABLES
       $LISTEN_FDS, $LISTEN_PID, $LISTEN_FDNAMES
           See sd_listen_fds(3).

           Added in version 230.

       $SYSTEMD_LOG_TARGET, $SYSTEMD_LOG_LEVEL, $SYSTEMD_LOG_TIME, $SYSTEMD_LOG_COLOR,
       $SYSTEMD_LOG_LOCATION
           Same as in systemd(1).

           Added in version 230.

EXAMPLES
       Example 1. Run an echo server on port 2000

           $ systemd-socket-activate -l 2000 --inetd -a cat

       Example 2. Run a socket-activated instance of systemd-journal-gatewayd(8)

           $ systemd-socket-activate -l 19531 /usr/lib/systemd/systemd-journal-gatewayd

SEE ALSO
       systemd(1), systemd.socket(5), systemd.service(5), systemd-run(1), sd_listen_fds(3),
       sd_listen_fds_with_names(3), cat(1)

systemd 255                                                               SYSTEMD-SOCKET-ACTIVATE(1)
systemd-socket-activate(1)
NAME SYNOPSIS DESCRIPTION OPTIONS ENVIRONMENT VARIABLES EXAMPLES SEE ALSO

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