For logical multicasting in overlay networks, at a data processing system, an original unicast packet is received from a first component in a first computing node in an overlay network. To cause multicasting in the overlay network the received original unicast packet was unicast by the first computing node only to the data processing system, and a multicast data structure for the overlay network is maintained only by the data processing system, the multicast data structure containing information of each receiver that is configured to receive unicast packets during logical multicasting in the overlay network. From a set of subscriber receivers in the multicast data structure, a subset of the subscriber receivers is selected. A copy of the original unicast packet is unicast to each subscriber receiver in the subset.