In a web based imaging environment, a user accesses a destination service representing a printer having manual duplex printing capability, and selects a manual duplex option. The method comprises assigning link weights to nodes within an IP backbone such that multicast forwarding paths and unicast forwarding paths are failure disjoint, and delivering undelivered multicast packets using IP unicast encapsulation to the loopback address of next hop router on a multicast tree upon linkinterface failure. For example, a new image having a pointer to a base image being executed may be created, wherein the new image may be empty when created, and wherein data may be written to the new image in response to any files being created, deleted, modified, or otherwise accessed during execution of the base image within the virtual machine.