McDewey

Note: Before you load split IP multicast traffic across equal-cost paths over a tunnel, configure CEF per-packet load balancing or else the GRE packets cannot be load balanced per packet. For other methods to load share in multicast environments, see Load Splitting IP Multicast Traffic over ECMP. Configure IP Multicast to Load Balance Across all Available Equal-Cost Paths In the figure, Router 75b has three equal-cost paths back to the Source (10.1.1.1). You want to load-balance the multicast traffic across all three links. Possible Fixes As you saw in the Multiple Equal Cost Paths Result in Unwanted RPF Behavior section, Protocol Independent Multicast (PIM) only chooses one interface for the RPF check and prunes the others. This means load balancing does not occur. In order to load-balance, you need to remove PIM from the redundant links and create a tunnel between Router 75a and Router 75b. You can then load-balance at the link level, and IP runs over the tunnel. These are the configurations for the tunnel. Router 75a

interface Tunnel0 ip address 10.6.1.1 255.255.255.0 ip pim sparse-dense-mode tunnel source Ethernet0/0 tunnel destination 10.5.1.1 ! interface Ethernet0/0 ip address 10.1.1.2 255.255.255.0 ip pim sparse-dense-mode ! interface Ethernet0/1 ip address 10.2.1.1 255.255.255.0 ! interface Ethernet0/2 ip address 10.3.1.1 255.255.255.0 ! interface Ethernet0/3 ip address 10.4.1.1 255.255.255.0