This disclosure describes techniques for improving speed of network convergence after node failure. In one example, a method includes storing, by SDN controller, an underlay routing table having routes for an underlay network of a data center and an overlay routing table having a set of routes for a virtual network of an overlay network for the data center, wherein the underlay network includes physical network switches, gateway routers, and a set of virtual routers executing on respective compute nodes of the data center; installing, within the underlay routing table, a route to a destination address assigned to a particular one of the virtual routers as an indicator of a reachability status to the particular virtual router in the underlay network. The SDN controller controls, based on presence or absence of the route within the underlay routing table, advertisement of the routes for the virtual network of the overlay network.