OpenBSD manual page server

Manual Page Search Parameters

RELAYD(8) System Manager's Manual RELAYD(8)

relaydrelay daemon

relayd [-dnv] [-D macro=value] [-f file]

relayd is a daemon to relay and dynamically redirect incoming connections to a target host. Its main purposes are to run as a load-balancer, application layer gateway, or transparent proxy. The daemon is able to monitor groups of hosts for availability, which is determined by checking for a specific service common to a host group. When availability is confirmed, layer 3 and/or layer 7 forwarding services are set up by relayd.

Layer 3 redirection happens at the packet level; to configure it, relayd communicates with pf(4). To allow relayd to properly set up pf(4) rules, the following line is required in the filter section of pf.conf(5):

anchor "relayd/*"

Layer 7 relaying happens at the application level and is handled by relayd itself. Various application level filtering and protocol-specific load-balancing options are available for relays.

relayd works in terms of the following : relays, protocols, redirections, and tables. A represents a layer 7 load-balancing instance. Each instance translates to a listening TCP or UDP port. A defines which actions, if any, are taken on the packet payload as data crosses a relay. A represents a layer 3 load-balancing instance. Each instance translates to a pf(4) rdr-to rule being added. A represents a group of hosts which can be checked for availability using the same method. Each table contains at least one host. If a table is used in a layer 3 load-balancing instance, it will be mapped to a pf(4) table containing only those hosts which are up.

All these entities can be configured in relayd.conf(5), and relayctl(8) can be used to alter or report on the status of each entity.

The options are as follows:

Define macro to be set to value on the command line. Overrides the definition of macro in the configuration file.
Do not daemonize. If this option is specified, relayd will run in the foreground and log to .
Specify an alternative configuration file. The default is /etc/relayd.conf.
Configtest mode. Only check the configuration file for validity.
Produce more verbose output.

Default configuration file.
UNIX-domain socket used for communication with relayctl(8).

relayd.conf(5), relayctl(8)

The relayd program, formerly known as hoststated, first appeared in OpenBSD 4.1. It was renamed to relayd in OpenBSD 4.3.

The relayd program was written by Pierre-Yves Ritschard <> and Reyk Floeter <>.

July 27, 2015 OpenBSD-7.1