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

NAME

       SMCRoute - Static Multicast Router (-Interface) - Version 0.95

SYNOPSIS

       smcroute < options > < commands >

       options
	      -d  -  start daemon
	      -v  -  verbose output
	      -D  -  enable debug logging

       commands - common
	      -h  -  print help
	      -k  -  kill daemon

       commands - multicast routing related
	      -a <InputIntf> <OriginIpAdr> <McGroupAdr> <OutputIntf> [<OutputIntf>] ...
		 -  add route
	      -r <InputIntf> <OriginIpAdr> <McGroupAdr>
		 -  remove route

       commands - multicast signaling related
	      -j <InputIntf> <McGroupAdr>  - join MC group
	      -l <InputIntf> <McGroupAdr>  - leave MC group

DESCRIPTION

       SMCRoute  is  a command line tool to manipulate the multicast routes of the Linux kernel. It supports both IPv4 and IPv6 multicast routing.
       SMCRoute can be used as an alternative to dynamic multicast routers like 'mrouted' in situations where static multicast	routes	should	be
       maintained and/or no proper IGMP or MLD signaling exists.

       Generally multicast routes exists in the kernel only as long as smcroute or another multicast routing daemon is running. Only one multicast
       routing daemon can be active at a time, so it's impossible to run smcroute and e.g. 'mrouted' at the same time.

       The -d option smcroute is used to start the smcroute daemon. Otherwise, smcroute searches for an already running smcroute daemon and passes
       the commands to it. The -k option will terminate a running daemon.

       Multicast routes can be added with the -a command and removed with the -r command.

       A  multicast  route  is	defined  by  an  input	interface  (<IntputIntf>),  a unicast IP origin address (<OriginIpAdr>), a multicast group
       (<McGroupAdr>) and a list of output interfaces (<OutputIntf> ...).

       The origin and multicast group addresses must both be IPv4 addresses or IPv6 addresses. If IPv4 addresses are specified then SMCRoute  will
       operate	on  the IPv4 multicast routes. If IPv6 addresses are specified then SMCRoute will operate on the IPv6 multicast routes. The output
       interfaces must not be given with the -r as the first three parameter are sufficient to identify the route to remove.

       The intention of SMCRoute is to help in situation where dynamic multicast routing does not work properly, but dynamic multicast routing	is
       in  nearly  all cases the preferred solution. SMCRoute supports dynamic multicast routing with the multicast group 'join' -j and 'leave' -l
       commands. For both commands the input interface on which the multicast sessions should be received (<InputIntf>) and  the  multicast  group
       address <McGroupAdr> must be given. The <McGroupAdr> may be an IPv4 or IPv6 address.

       Superuser rights are necessary to start the smcroute daemon or to communicate with the daemon.

OPTIONS

       -d     Starts the smcroute daemon before any of the optional following commands are executed.

       -v     Gives verbose output in some error situations (don't expect too much, check syslog instead).

       -D     Gives additional debug messages in normal use (don't expect too much, see syslog instead).

COMMANDS

       -a     <InputIntf> <OriginIpAdr> <McGroupAdr> <OutputIntf> [<OutputIntf>] ...

	      The  command is passed to the daemon that adds the given multicast route to the kernel's routing table.  <InputIntf> can be any net-
	      work interface as listed by 'ifconfig' or 'ip link list' (incl. tunnel interfaces), but not the loopback	interface.   <OriginIpAdr>
	      is  the source IP address of the multicast packets that will be routed by this entry. It is a unicast IPv4 or IPv6 address and not a
	      multicast IP address.  <McGroupAdr> is the IPv4 or IPv6 address of the multicast group that will be forwarded.  <OutputIntf>  [<Out-
	      putIntf>]  ...  is a list of one or more network interfaces to which the multicast packets will be forwarded. The same rules for the
	      selection of output interfaces applies as for the input interface.

	      Warning, by using multiple output interfaces (traffic multiplication), using the input interface also as	output	interface  (direct
	      loop) or constructing some other forms of indirect loop you can flood you network.

       -r     <InputIntf> <OriginIpAdr> <McGroupAdr>

	      The  command is passed to the daemon that removes a multicast route previously added with the -a command. The parameters are identi-
	      cal except to the omitted list of <OutputIntf>.

       -j     <InputIntf> <McGroupAdr>

	      The command is passed to the daemon that passes it to the kernel. The kernel then tries to join the multicast group <McGroupAdr>	on
	      interface  <InputIntf> by starting IGMP (or MLD if <McGroupAdr> is an IPv6 address) signaling on <InputIntf>.  This signaling may be
	      received by routers connected to <InputIntf>'s network that support IGMP/MLD multicast signaling and then hopfuly  start	forwarding
	      of the requested multicast session to <InputIntf>'s network.

	      With  this  command smcroute allows the integration of nodes that needs static multicast routing into dynamic multicast routing net-
	      works.

       -l     <InputIntf> <McGroupAdr>

	      The command is passed via the daemon to the kernel that initiate a 'leave' for a previously 'joined' multicast group.

LIMITS

       The current version compiles and runs fine with the Linux kernel version 2.4. The known limits are:

       Multicast routes: more then 200

       Multicast group membership: max. 20

FILES

       /proc/net/ip_mr_cache
	      - contains the active IPv4 multicast routes

       /proc/net/ip_mr_vif
	      - contains the IPv4 'virtual' interfaces used by the active multicast routing daemon

       /proc/net/ip6_mr_cache
	      - contains the active IPv6 multicast routes

       /proc/net/ip6_mr_vif
	      - contains the IPv6 'virtual' interfaces used by the active multicast routing daemon

       /var/run/smcroute
	      - IPC socket created by the smcroute daemon

SEE ALSO

       mrouted

BUGS

       The English wording of this man page.

AUTHORS

       smcroute was originally written by Carsten Schill <carsten@cschill.de>, support for IPv6 was added by Todd Hayton  <todd.hayton@gmail.com>,
       support for FreeBSD was added by Micha Lenk <micha@debian.org>.

       The   source   code   is  now  maintained  by  Todd  Hayton  <todd.hayton@gmail.com>,  Micha  Lenk  <micha@debian.org>  and  Julien  BLACHE
       <jblache@debian.org>.

       The current version is available at: http://alioth.debian.org/projects/smcroute

TIPS

       A lot of extra information is sent under the daemon facility and the debug priority to the syslog daemon.

								  August 08, 2011						       smcroute(8)