1. A method of satisfying a request for a particular file system object, by a second storage processor having a cache, in a common block file system bound to a first storage processor, a common message interface (CMI) provided for communicating between the first storage processor and the second storage processor, the method comprising: examining the request for the particular file system object for an instruction leading to modification of a metadata object of the common block file system, the common block file system having metadata objects arranged as a tree structure, a copied portion of the tree structure being stored in the cache of the second storage processor; upon finding that the request includes an instruction leading to a modification of the metadata object of the common block file system: forwarding the request for the particular file system object to the first storage processor via the CMI to enable the first storage processor to physically satisfy the request for the particular file system object; upon not finding that the request includes an instruction leading to such a modification: referencing a leaf node of a branch of the portion of the tree structure, the leaf node containing the metadata object including an identifier for physically satisfying the request for the particular file system object; and accessing the particular file system object using the identifier for physically satisfying the request for the particular file system object; and returning the particular file system object to a requestor of the particular file system object; wherein the identifier is a logical address pointing to a physical address in a nonvolatile storage medium at which the particular file system object is stored, the logical address being assigned to the physical address by the common block file system, wherein a second common block file system is bound to the second storage processor, wherein the second storage processor is constructed and arranged to store, in the cache of the second storage processor, (i) copies of first metadata objects, the first metadata objects including first indirect blocks containing pointers to physical blocks of files of the common block file system and (ii) second metadata objects, the second metadata objects including indirect blocks containing pointers to physical blocks of files of the second common block file system, the first metadata objects including the metadata object that includes the identifier for physically satisfying the request for the particular file system object, and wherein the first storage processor has a cache, the first storage processor being constructed and arranged to store, in the cache of the first storage processor, (i) copies of the second metadata objects and (ii) the first metadata objects.