The disclosure describes examples where a first data center includes a first gateway router, a first set of computing devices, and a second set of computing devices. The first set of computing devices is configured to execute a software defined networking (SDN) controller cluster to facilitate operation of one or more virtual networks within the first data center. The second set of computing devices is configured to execute one or more control nodes to exchange route information, between the first gateway router and a second gateway router of a second data center different than the first data center, for a virtual network between computing devices within the second data center, and to communicate control information for the second data center to the second set of computing devices, wherein the one or more control nodes form a subcluster of the SDN controller cluster.