DVMRPD(8) | System Manager's Manual | DVMRPD(8)

# NAME

`dvmrpd` — Distance Vector Multicast Routing Protocol (DVMRP) daemon

# SYNOPSIS

`dvmrpd` | [`-dnv`] [`-f` file]

# DESCRIPTION

`dvmrpd` is the Distance Vector Multicast Routing Protocol (DVMRP) daemon, which manages multicast routing tables. This implementation supports DVMRP version 3.255, thus it is only capable of maintaining IPv4 multicast routing tables.

DVMRP uses a distance vector routing algorithm to build reverse path multicast delivery trees. A flood and prune approach is used to determine which branches in the network have multicast listeners. The usual drawbacks of a distance vector route protocol applies to DVMRP: slow convergence and scalability issues.

DVMRP routers communicate via the multicast group 224.0.0.4 All DVMRP Routers. IP protocol number 2 (IGMP) is used, furthermore DVMRP packets omit the use of TCP and UDP.

It is possible to interconnect multicast networks with the use of tunnels. Tunnels can traverse routers and networks not supporting multicast. `dvmrpd` does not support tunneling as described in RFC 1075, since it has been abandoned. `dvmrpd` can tunnel multicast traffic using generic solutions such as gre(4).

DVMRP is used for handling multicast routing exclusively. It is not required that a unicast routing protocol is used in conjunction with DVMRP.

To have `dvmrpd` enabled at boot time, use “rcctl enable dvmrpd”, which sets

`dvmrpd_flags=""`

in rc.conf.local(8).

A running `dvmrpd` can be controlled with the dvmrpctl(8) utility.

The options are as follows:

`-d`
  Do not daemonize. If this option is specified, `dvmrpd` will run in the foreground and log to stderr.
`-f` file
  Specify an alternative configuration file.
`-n`
  Configtest mode. Only check the configuration file for validity.
`-v`
  Produce more verbose output.

# FILES

/etc/dvmrpd.conf
  Default `dvmrpd` configuration file.
/var/run/dvmrpd.sock
  UNIX-domain socket used for communication with dvmrpctl(8).

# SEE ALSO

dvmrpd.conf(5), dvmrpctl(8)

# STANDARDS

DVMRP Version 3, draft-ietf-idmr-dvmrp-v3-11, August 2000.

# HISTORY

The `dvmrpd` program first appeared in OpenBSD 4.0.

March 2, 2023 | Debian