General configuration elements

PM-DM requires you to configure the following elements:

  • IP routing enabled on all routing switches you want to carry routed multicast traffic.

  • Routing methods needed to reach the interfaces (VLANs) on which you want multicast traffic available for hosts in your network:
    • Enable RIP or OSPF at both the global and VLAN levels on the routers where there are connected hosts that may issue multicast joins.

    • Configure static routes to and from the destination subnets.

  • Enable IP multicast routing.

  • Enable IGMP on each VLAN when that VLAN has hosts that you want to join multicast groups. Repeat this action on every switch and router belonging to the VLAN.

  • Enable PIM-DM at the global level on the routing switch and on the VLANs where you want to allow routed multicast traffic.


When you initially enable PIM-DM, it is recommended that you leave the PIM-DM configuration parameters at their default settings. From the default, you can assess performance and make configuration changes when needed.