A virtual appliance may be provided with firmware images that may be simulated in a run-time environment prior to loading into a network component. A kernel may be mapped to a virtual appliance image providing a virtual operating system image. Updates to the virtual appliance may provide updated versions of the virtual operating system image by mapping the updated virtual appliance image to an updated kernel. Various versions of the virtual operating system image may be stored and loaded into the virtual appliance without needing to downgrade a previous version of the operating system.