diff options
| -rw-r--r-- | usr.sbin/dvmrpd/dvmrpd.8 | 47 |
1 files changed, 44 insertions, 3 deletions
diff --git a/usr.sbin/dvmrpd/dvmrpd.8 b/usr.sbin/dvmrpd/dvmrpd.8 index e88c4f6f142..252de013fff 100644 --- a/usr.sbin/dvmrpd/dvmrpd.8 +++ b/usr.sbin/dvmrpd/dvmrpd.8 @@ -1,4 +1,4 @@ -.\" $OpenBSD: dvmrpd.8,v 1.3 2007/05/31 19:20:23 jmc Exp $ +.\" $OpenBSD: dvmrpd.8,v 1.4 2008/04/28 05:39:19 norby Exp $ .\" .\" Copyright (c) 2004, 2005, 2006 Esben Norby <norby@openbsd.org> .\" @@ -14,7 +14,7 @@ .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. .\" -.Dd $Mdocdate: May 31 2007 $ +.Dd $Mdocdate: April 28 2008 $ .Dt DVMRPD 8 .Os .Sh NAME @@ -29,7 +29,48 @@ is the Distance Vector Multicast Routing Protocol .Pq DVMRP daemon which manages multicast routing tables. -Its main purpose is keeping multicast routing tables in sync. +This implementation supports DVMRP version 3.255, thus it is +only capable of maintaining IPv4 multicast routing tables. +.Pp +DVMRP is using 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. +.Pp +DVMRP routers communicate via the multicast group 224.0.0.4 +All DVMRP Routers. The IP protocol number 2 +.Pq IGMP +is used, furthermore DVMRP packets omit the use of TCP and UDP. +.Pp +It is possible to interconnect multicast networks with the use of tunnels. +Tunnels can traverse routers and networks not supporting multicast. +.Nm +does not support tunneling as described in +RFC 1075 +since it has been abandoned. +.Nm +can tunnel multicast traffic using generic solutions, e.g. +.Xr gre 4 . +.Pp +DVMRP is used for handling multicast routing exclusively. +It is not required that a unicast routing protocol is used in +conjunction with DVMRP. +.Pp +.Nm +is usually started at boot time, and can be enabled by +setting the following in +.Pa /etc/rc.conf.local : +.Pp +.Dl dvmrpd_flags=\&"\&" +.Pp +See +.Xr rc 8 +and +.Xr rc.conf 8 +for more information on the boot process +and enabling daemons. .Pp A running .Nm |