DVMRPD(8) OpenBSD System Manager's Manual DVMRPD(8)NAME
dvmrpd - Distance Vector Multicast Routing Protocol 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.
dvmrpd is usually started at boot time, and can be enabled by setting the
following in /etc/rc.conf.local:
dvmrpd_flags=""
See rc(8) and rc.conf(8) for more information on the boot process and
enabling daemons.
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 ALSOdvmrpd.conf(5), dvmrpctl(8)
DVMRP Version 3, draft-ietf-idmr-dvmrp-v3-11, August 2000.
HISTORY
The dvmrpd program first appeared in OpenBSD 4.0.
OpenBSD 4.9 October 22, 2009 OpenBSD 4.9