SYSTEMD-SOCKET-PROXYD(8) systemd-socket-proxyd SYSTEMD-SOCKET-PROXYD(8)
NAME
systemd-socket-proxyd - Bidirectionally proxy local sockets to another
(possibly remote) socket.
SYNOPSIS
systemd-socket-proxyd [OPTIONS...] HOST:PORT
systemd-socket-proxyd [OPTIONS...] UNIX-DOMAIN-SOCKET-PATH
DESCRIPTION
systemd-socket-proxyd is a generic socket-activated network socket
forwarder proxy daemon for IPv4, IPv6 and UNIX stream sockets. It may
be used to bi-directionally forward traffic from a local listening
socket to a local or remote destination socket.
One use of this tool is to provide socket activation support for
services that do not natively support socket activation. On behalf of
the service to activate, the proxy inherits the socket from systemd,
accepts each client connection, opens a connection to a configured
server for each client, and then bidirectionally forwards data between
the two.
This utility's behavior is similar to socat(1). The main differences
for systemd-socket-proxyd are support for socket activation with
"Accept=false" and an event-driven design that scales better with the
number of connections.
OPTIONS
The following options are understood:
-h, --help
Print a short help text and exit.
--version
Print a short version string and exit.
EXIT STATUS
On success, 0 is returned, a non-zero failure code otherwise.
EXAMPLES
Simple Example
Use two services with a dependency and no namespace isolation.
Example 1. proxy-to-nginx.socket
[Socket]
ListenStream=80
[Install]
WantedBy=sockets.target
Example 2. proxy-to-nginx.service
[Unit]
Requires=nginx.service
After=nginx.service
[Service]
ExecStart=/usr/lib/systemd/systemd-socket-proxyd /tmp/nginx.sock
PrivateTmp=yes
PrivateNetwork=yes
Example 3. nginx.conf
[...]
server {
listen unix:/tmp/nginx.sock;
[...]
Example 4. Enabling the proxy
# systemctl enable proxy-to-nginx.socket
# systemctl start proxy-to-nginx.socket
$ curl http://localhost:80/
Namespace Example
Similar as above, but runs the socket proxy and the main service in the
same private namespace, assuming that nginx.service has PrivateTmp= and
PrivateNetwork= set, too.
Example 5. proxy-to-nginx.socket
[Socket]
ListenStream=80
[Install]
WantedBy=sockets.target
Example 6. proxy-to-nginx.service
[Unit]
Requires=nginx.service
After=nginx.service
JoinsNamespaceOf=nginx.service
[Service]
ExecStart=/usr/lib/systemd/systemd-socket-proxyd 127.0.0.1:8080
PrivateTmp=yes
PrivateNetwork=yes
Example 7. nginx.conf
[...]
server {
listen 8080;
listen unix:/tmp/nginx.sock;
[...]
Example 8. Enabling the proxy
# systemctl enable proxy-to-nginx.socket
# systemctl start proxy-to-nginx.socket
$ curl http://localhost:80/
SEE ALSO
systemd(1), systemd.socket(5), systemd.service(5), systemctl(1),
socat(1), nginx(1), curl(1)
systemd 219 SYSTEMD-SOCKET-PROXYD(8)