|MROUTED(8)||System Manager's Manual (smm)||MROUTED(8)|
mroutedis the original implementation of the Distance-Vector Multicast Routing Protocol (DVMRP), RFC 1075. A dynamic (automatic) multicast routing daemon, that also supports static routing. See mrouted.conf(5) for information on the
mroutedis simple to use. DVMRP is derived from RIP, RFC 1058, which means
mroutedworks stand-alone without any extra network setup required. You can get up and running in a matter of minutes.
mroutedmaintains topological knowledge via DVMRP, upon which it implements a multicast datagram forwarding algorithm called Reverse Path Multicasting.
mroutedforwards multicast datagrams along the shortest (reverse) path tree rooted at the subnet on which the datagram originates. The multicast delivery tree may be thought of as a broadcast delivery tree that has been pruned back so that it does not extend beyond those subnetworks that have members of the destination group. Hence, datagrams are not forwarded along those branches which have no listeners of the multicast group. The IP time-to-live of a multicast datagram can be used to limit the range of multicast datagrams. In order to support multicasting among subnets that are separated by (unicast) routers that do not support IP multicasting, you can set up GRE tunnels. However,
mroutedincludes (built-in) support for IP-in-IP tunnels, which are virtual point-to-point links between pairs of DVMRP capable routers located anywhere in an internet. IP multicast packets are encapsulated for transmission through tunnels, so that they look like normal unicast datagrams to intervening routers and subnets. The encapsulation is added on entry to a tunnel, and stripped off on exit from a tunnel. The tunneling mechanism allows
mroutedto establish a virtual internet, for the purpose of multicasting only, which is independent of the physical internet, and which may span multiple Autonomous Systems. This capability is intended for experimental support of internet multicasting only, pending widespread support for multicast routing by the regular (unicast) routers.
mroutedsuffers from the well-known scaling problems of any distance-vector routing protocol, and does not support hierarchical multicast routing. A more common practice today is to set up GRE tunnels between multicast capable routers and limit
mroutedto run on a select number of interfaces listed in the configuration.
mroutedhandles multicast routing only; there may or may not be unicast routing software running on the same machine as
mrouted. With the use of tunnels, it is not necessary for
mroutedto have access to more than one physical subnet in order to perform multicast forwarding.
mroutedto run in the foreground of the starting terminal, regardless of the
-lflag controls the (syslog) log level of each subsystem. Use '?' for a complete list of supported subsystems. Available subystems:
mrouted, or to adapt to site specific practices, e.g. "DVMRP", without renaming the binary. Note, this option only changes the base name of the files, not the location, which is system specific. On most systems this is /var/run/mrouted.pid, or /run/mrouted.pid, /run/mrouted.genid, /run/mrouted.sock, and /etc/mrouted.conf.
-soption if you still want to redirect log messages to the syslog.
-n, log messages are printed to stdout.
ip mrule add iif eth0 lookup 123 ip mrule add oif eth0 lookup 123
Note:Only available on Linux.
mroutedresponds to the following signals:
mroutedand reload the configuration file.
mroutedwrites its process ID to /var/run/mrouted.pid when it has completed its start up and is ready to receive signals.
mrouteddaemon when it has started up and is ready to receive commands.
’, optionally also with
-n, to get full logs of its interaction with the system. Particular problems include, but are not limited to:
Cannot enable multicast routing in kernel
options MROUTING # Multicast routing
Cannot join group 188.8.131.52: No buffer space available
mroutedhome page is ⟨https://github.com/troglobit/mrouted⟩
mrouted, listed in no particular order: David Waitzman,
|January 7, 2021||Debian|