Weighted multicast join load balance

A network device comprising:

• a memory;
• and
• one or more processors implemented in circuitry and configured to:
• receive messages from each of a plurality of ingress network devices for a network, wherein each of the messages specifies a multicast source and a multicast group, and at least one of the messages includes a field specifying an upstream multicast hop weight value for multicast traffic for the multicast source and the multicast group;
• determine, based on the received messages and the upstream multicast weight value specified by the at least one of the messages, a proportion of a plurality of multicast join messages to send to each of the plurality of ingress network devices;
• select, based on the determined proportions, one of the plurality of ingress network devices to which to send a multicast join message of the plurality of multicast join messages for the multicast source and multicast group;
• and
• send, according to the determined proportions, the given multicast join message to the selected one of the plurality of ingress network devices.

A non-transitory computer-readable medium encoded with instructions for causing a programmable processor of an egress network device to perform steps comprising:

• receiving messages from each of a plurality of ingress network devices for the network, wherein each of the messages specifies a multicast source and a multicast group, and at least one of the messages includes a field specifying an upstream multicast hop weight value for multicast traffic for the multicast source and the multicast group;
• determining, based on the received messages and the upstream multicast weight value specified by the at least one of the messages, a proportion of a plurality of multicast join messages to send to each of the plurality of ingress network devices;
• selecting, based on the determined proportions, one of the plurality of ingress network devices to which to send a given multicast join message of the plurality of multicast join messages for the multicast source and multicast group;
• and
• sending, according to the determined proportions, the given multicast join message to the selected one of the plurality of ingress network devices.