Command Reference Guide Frame Relay Sub-Interface Config Command Set
61200510L1-35E Copyright © 2005 ADTRAN 905
ip mcast-stub downstream
Use the ip mcast-stub downstream command to enable multicast forwarding and IGMP (router mode) on
an interface and place it in multicast stub downstream mode. Use the no form of this command to disable.
Syntax Description
No subcommands.
Default Values
By default, this command is disabled.
Applicable Platforms
This command applies to the NetVanta 1000R, 3000, 4000, and 5000 and Total Access 900 Series units.
Command History
Release 7.1 Command was introduced.
Functional Notes
This command is used in IP multicast stub applications in conjunction with the ip mcast-stub
helper-address and ip mcast-stub upstream commands. Downstream interfaces connect to segments
with multicast hosts. Multiple interfaces may be configured in downstream mode; however, interfaces
connecting to the multicast network (upstream) should not be configured in downstream mode. Interfaces
configured as downstream should have the lowest IP address of all IGMP-capable routers on the
connected segment in order to be selected as the designated router and ensure proper forwarding. Refer
to
ip mcast-stub helper-address <ip address> on page 434 for more information.
Usage Examples
The following example enables multicast forwarding and IGMP on the interface:
(config)#interface frame-relay 1.16
(config-fr 1.16)#ip mcast-stub downstream