Patent attributes
A method and apparatus of a device that updates a software image for a network element is described. In an exemplary embodiment, a device receives a signal to update the network element with the new software image, where the network element includes a plurality of hardware forwarding engines and a control plane. The device further boots the control plane with the new software image, where the booting is accomplished without restarting the control plane. In one embodiment, the device boots the control plane by chain booting from a current software image to the new software image. The device additionally restarts and reconfigures the plurality of hardware forwarding engines. In a further embodiment, the device additionally prefills one or more queues in the hardware forwarding engines with keep-alive messages. These keep-alive messages are transmitted during the time that the control plane is being restarted. In a further embodiment, the hardware forwarding engines are reconfigured without restarting them.