1. A method for migrating a virtual appliance from a first server grid to a second server grid via a communication network, the method comprising: running a first instance of the virtual appliance at the first server grid, wherein the first server grid has associated therewith a first portion of virtualized computing resources representing computing resources associated with a first plurality of physical servers, wherein the first instance of the virtual appliance has associated therewith a first instance of a virtual machine and a first instance of a virtual volume; identifying a first portion of updated or modified data relating to a first disk image stored at the first instance of the virtual volume, for use by the first instance of the virtual appliance; establishing a connection over the communication network from the first server grid to the second server grid; transferring, to the second server grid, information relating to the first portion of updated or modified data relating to the first disk image; modifying, using the first portion of updated or modified data, a second disk image for use by a second instance of the virtual appliance at the second server grid; and starting, using the modified second disk image, the second instance of the virtual appliance at the second server grid; wherein the second instance of the virtual appliance includes a second instance of the virtual machine and a second instance of the virtual volume.