Patent ID: 8799422

Claim:
A method comprising: a routing component of a network device, running a first virtual machine executing a first operating system that controls a routing communication session between the network device and a second network device, and controls an in-service configuration update (ISCU) of the routing component; in response to receiving an ISCU request with the first virtual machine to update the first operating system for the routing component, initializing a second virtual machine on the routing component of the network device; installing a second operating system on the second virtual machine running on the routing component of the network device, wherein the second operating system is different than the first operating system; transferring control of the routing communication session from the first operating system on the first virtual machine to the second operating system on the second virtual machine running on the routing component of the network device while continuing to forward data packets from the network device to the second network device; and after transferring control of the routing communication session to the second operating system on the second virtual machine, shutting down the first virtual machine.