Patent ID: 9185030
Filing Date: 2015-11-10
Classification: H04L

Abstract:
1. A method, comprising: operating a physical packet switching device according to a first operating version, wherein the physical packet switching device includes a plurality of physical line cards with each of the plurality of physical line cards including interfaces for sending and receiving packets and a physical network processor processing packets according to microcode and a processor performing line card control, a physical route processor engine deriving and providing forwarding information to each of the plurality of physical line cards; and a physical switching fabric or crossbar communicatively coupling the plurality of physical line cards, including communicating packets among the plurality of line cards, and the physical route processor engine; and said operating the physical packet switching device according to the first operating version includes: operating a first routing instance on a first virtual machine on each of said processors performing line card control to maintain a first forwarding information base, operating said physical network processors according to said microcode according to the first operating version to forward packets according to the first forwarding information base, and operating a first route processor virtual machine on the physical route processor engine to maintain a first routing information base based on routing information packets exchanged with other packet switching devices and to update said first routing instances with first forwarding information from first routing information; wherein the method includes: simultaneously operating the physical packet switching device according to the first operating version and a second operating version; and marking each particular packet of a plurality of packets processed by said network processors on the plurality of line cards with an indication of which version of the first and second operating versions that said particular packet was processed, and correspondingly processing by the physical packet switching device said particular packet according to said marking.