A method for performing virtual archiving by a backup server comprising: applying an archiving rule to a backup catalog, wherein the backup catalog is a central repository that contains information for one or more backup images, wherein each of the one or more backup images is associated with a backup catalog, wherein each of the one or more backup images is created by a backup server for a client, and wherein applying an archiving rule to the backup catalog produces a list of items to be archived on the client; generating a virtual archive catalog for virtual archive images based at least in part on a result of applying the archiving rule to the backup catalog, wherein the virtual archive image contains items to be archived at the client which are located in one or more backup images; determining that a particular back up image of the one or more backup images expires earlier than a virtual image archive associated with the particular backup image; and in response to such a determination, converting the particular backup image into a real archive image before marking the particular backup image as expired, wherein the converting is performed in place without data movement; wherein converting the backup image into the archive image in place is performed by clearing out items not required for archive images from the expired backup images, such that data needing to be archived will remain where they are on the expired backup image and the expired backup image becomes an archive image and other items on the expired backup image not required for the archive image are cleaned out and the storage space for the other objects is reclaimed. applying an archiving rule to a backup catalog, wherein the backup catalog is a central repository that contains information for one or more backup images, wherein each of the one or more backup images is associated with a backup catalog, wherein each of the one or more backup images is created by a backup server for a client, and wherein applying an archiving rule to the backup catalog produces a list of items to be archived on the client; generating a virtual archive catalog for virtual archive images based at least in part on a result of applying the archiving rule to the backup catalog, wherein the virtual archive image contains items to be archived at the client which are located in one or more backup images; determining that a particular back up image of the one or more backup images expires earlier than a virtual image archive associated with the particular backup image; and in response to such a determination, converting the particular backup image into a real archive image before marking the particular backup image as expired, wherein the converting is performed in place without data movement; wherein converting the backup image into the archive image in place is performed by clearing out items not required for archive images from the expired backup images, such that data needing to be archived will remain where they are on the expired backup image and the expired backup image becomes an archive image and other items on the expired backup image not required for the archive image are cleaned out and the storage space for the other objects is reclaimed.