Scalable overlay multicast routing

A computer system, comprising:

• one or more processors;
• and
• a non-transitory computer readable medium comprising instruction that, when executed by the one or more processors, cause the computer system to perform a method of reducing congestion within a network, the network comprising a plurality of host machines and a plurality of virtual computing instances (VCIs) running on the plurality of host machines, the method comprising:
• receiving, by an edge services gateway, membership information for a group, wherein the membership information identifies a subset of the plurality of host machines;
• receiving, by the edge services gateway, from an external network that is outside of the network, a multicast packet directed to the group;
• in response to the receiving of the multicast packet, selecting, by the edge services gateway, from the subset of the plurality of host machines identified in the membership information for the group, a single replicator host machine for the multicast packet;
• and
• sending, by the edge services gateway, to the single replicator host machine via unicast, the multicast packet along with metadata indicating that the single replicator host machine is to replicate the multicast packet to remaining host machines of the subset of the plurality of host machines identified in the membership information for the group.

A non-transitory computer readable medium comprising instructions that, when executed by a processor of a computer system, cause the computer system to perform a method of reducing congestion within a network, the network comprising a plurality of host machines and a plurality of virtual computing instances (VCIs) running on the plurality of host machines, the method comprising:

• receiving, by an edge services gateway, membership information for a group, wherein the membership information identifies a subset of the plurality of host machines;
• receiving, by the edge services gateway, from an external network that is outside of the network, a multicast packet directed to the group;
• in response to the receiving of the multicast packet, selecting, by the edge services gateway, from the subset of the plurality of host machines identified in the membership information for the group, a single replicator host machine for the multicast packet;
• and
• sending, by the edge services gateway, to the single replicator host machine via unicast, the multicast packet along with metadata indicating that the single replicator host machine is to replicate the multicast packet to remaining host machines of the subset of the plurality of host machines identified in the membership information for the group.