1. A computer-implemented method for providing variable length duplication of a data stream on a fixed block file system, the method comprising: receiving, by a processor, a data stream, wherein the data stream comprises of a plurality of data items; determining, by the processor, whether a first segment of data items of the plurality of data items exists on a storage volume; storing, by the processor, the first segment of data items on the storage volume if the first segment of data items does not exist on the storage volume, otherwise deduplicating the first segment of data items with the storage volume; and storing, by the processor in a data structure, an association between a logical identifier describing a location of the first segment of data items in the data stream, a physical identifier describing a physical location of the first segment of data items on the storage volume, and a length of the first segment of data items, wherein the first segment of data items can be retrieved from the storage volume using the logical identifier and the length, wherein a data item can be retrieved from the storage volume using a read request comprising a read logical offset and a read length.