A mechanism to allow switch manager software to determine bandwidth consumption and cooperate with a VM manager. Counter hardware measures network traffic between the various ports of the switch stack. The switch manager determines the MAC or IP addresses of devices connected to each port, which are provided to the VM manager to correlate VMs to ports. The switch manger collects statistics from the counter hardware to determine traffic flow levels between the various ports. A list of high traffic port pairs is provided to the VM manager. In conjunction with each port is a list of available ports, identified by at least one MAC or IP address associated with that port, having capacity to receive the traffic of the respective ports of each port pair and provided in order of least to most hops, to allow the VM manager to select a closer port to receive a migrated VM.