Scaling address resolution for massive data centers

There is provided a network device disposed at an interface between an access segment and an interconnecting layer of a data center. The network device includes an address resolution processor configured to receive an address request addressed to virtual machines in a transmission domain of the network device. The address request specifying a source layer 2 address, requesting a layer 2 address of a target virtual machine in the data center, and specifying a layer 3 address of the target virtual machine. The network device is further configured to transmit a local message over the first access segment requesting the respective layer 2 address of a virtual machine which has the specified layer 3 address. In response to receiving a reply, the network device transmits a message to the specified source layer 2 address to provide the layer 2 address of the network device and the specified layer 3 address.