Described are systems and methods of monitoring network health and traffic. Monitoring network health and traffic can include sending a request to a compute instance to trigger a response from the compute instance, monitoring, via a network virtualization device, communications from a virtual network interface card (VNIC) associated with the compute instance, storing information indicative of a last received packet by the VNIC, monitoring the stored information indicative of the last received packet to determine a health status of the compute instance associated with the VNIC, updating a table configured to track received responses from the compute instance, and notifying a downstream user of the health status of the compute instance.