This section provides information to configure IGMP and MLD using the command line interface.
Topics in this section include:
The routers use IGMP to manage membership for a given multicast session. IGMP is not enabled by default. When enabled, at least one interface must be specified in the IGMP context as IGMP is an interface function. Creating an interface enables IGMP. Traffic can only flow away from the router to an IGMP interface and to and from a PIM interface. A router directly connected to a source must have PIM enabled on the interface to that source. The traffic travels in a network from PIM interface to PIM interface and arrives finally on an IGMP enabled interface.
The IGMP CLI context allows you to specify an existing IP interface and modify the interface-specific parameters. Static IGMP group memberships can be configured to test multicast forwarding without a receiver host. When IGMP static group membership is enabled, data is forwarded to an interface without receiving membership reports from host members.
When static IGMP group entries on point-to-point links that connect routers to a rendezvous point (RP) are configured, the static IGMP group entries do not generate join messages toward the RP. When a host wants to receive multicast sessions it sends a join message for each multicast group it wants to join. Then, a leave message may be sent for each multicast group it no longer wishes to participate with.
A multicast router keeps a list of multicast group memberships for each attached network, and an interval timer for each membership. Hosts issue a Multicast Group Membership Report when they want to receive a multicast session. The reports are sent to all multicast routers.
Perform the following basic multicast configuration tasks:
Use the following CLI syntax to enable IGMP.
The following example displays the detailed output when IGMP is enabled.
To configure an IGMP interface:
Use the following CLI syntax to configure IGMP interfaces:
The following example displays the IGMP configuration:
To add an IGMP static multicast source:
Use the following CLI syntax to configure static group addresses and source addresses for the SSM translate group ranges:
The following example displays the configuration:
To add an IGMP static starg entry:
Use the following CLI syntax to configure static group addresses and add a static (*,G) entry:
The following example displays the configuration:
To configure IGMP parameters:
The following example displays the command usage to configure IGMP parameters:
The following example displays the SSM translation configuration:
Use the following CLI syntax to disable IGMP.
The following example displays the command usage to disable multicast:
The following example displays the configuration output: