Method and apparatus for packet processing by re-insertion into network interface circuitry. A method for handling a burst of packets sent to network interface circuitry includes checking for a connection table entry for received packets, and responsive to non-existence of the connection table entry for the received packets, sending the packets to network interface software for processing. The network interface software processing includes: building the connection table entry; processing the packets; and sending the packets as processed to the network interface circuitry. Additionally, a method for re-inserting a packet responsive to an active audit mode is described.