Systems and methods for implementing content sensitive routing over a wide area network (WAN)
Systems and methods for optimizing storage network functionality. The methods and systems of the present invention are particularly useful for optimizing storage network performance for cases in which some components of the network may be separated by significant distances and/or which include communication links with relatively limited bandwidth. In certain aspects, the present invention provides methods and systems for implementing access to and management of geographically distributed storage resources through multiple peer-to-peer storage network array management functions (AMFs) that may also be geographically distributed. The methods and systems of the present invention, in certain aspects, provide geographically aware cache sharing, cache replication, cache coherence, traffic routing, redundancy group structure, source and destination selection, pre-fetching of data, message gathering and other useful features.
1. A method for implementing preferred target selection for read operations by a given AMF in a storage network so that the read operations are directed toward data mirrors associated with that AMF, the network comprising an AMF access group (AAG), including a plurality of AMFs that share read and write access to a plurality of redundancy groups (RGs), wherein each AMF shares read and write access to a local RG (LRG) including a first plurality of storage resources and a remote RG including a second plurality of remote storage resources, the method comprising:
defining a hierarchy of read targets for each AMF, said hierarchy having an access priority order of storage resources, with resources in a LRG having higher priority than resources in a remote RG; and
in response to a read request received by an AMF, selecting resources for read access from among from the storage resources shared by that AMF as determined by the hierarchy priority order for that AMF.
2. The method of claim 1 , wherein the AAG includes two or more local AMF access groups (LAAGs), each LAAG being either remote from other LAAGs or communicably coupled to other LAAGs by a low bandwidth network link.
3. The method of claim 1 , further including accessing data identified in the read request (requested data) from a selected resource.
4. The method of claim 2 , further comprising returning data identified in the read request to the entity that sent the read request.
5. The method of claim 2 , wherein if the selected resource does not store data requested in the read request, accessing the requested data from the next resource on the hierarchy priority order.
6. A method for implementing preferred AMF selection, and source mirror selection for rebuild and data transfer operations in a storage network so that read/write traffic is confined as much as possible to the LRG associated with the target storage resource, the network comprising an AMF access group (AAG) including a plurality of AMFs that share read and write access to a plurality of redundancy groups (RGs), including a first RG including a first plurality of storage resources that are local to one or more first AMFs in the AAG and a second RG including a second plurality of remote storage resources that are local to one or more second AMFs in the AAG, said one or more first AMFs being remote from the one or more second AMFs, the method comprising:
in response to one of a data transfer request or a rebuild request received by an AMF, determining whether the received request identifies a resource in the first RG or the second RG;
selecting an AMF that is local to the determined RG from among the first or second AMFs within the AAG; and
processing the received request by the selected AMF.
7. A method for implementing preferred target selection for read operations by a given AMIF in a storage network in fail-over scenarios so that these read operations are directed toward the nearest surviving data mirror associated with that AMF, the network comprising an AMF access group (AAG), including a plurality of AMFs that share read and write access to a plurality of redundancy groups (RGs), wherein each AMF shares read and write access to a local RG (LRG) including a first plurality of storage resources and a remote RG including a second plurality of remote storage resources, the method comprising:
defining a hierarchy of read targets for each AMF, said hierarchy having an access priority order of storage resources, with resources in a LRG having higher priority than resources in a remote RG;
in response to a read request received by an AMF, selecting a resource for read access from among from the storage resources shared by that AMF as determined by the hierarchy priority order for that AMF,
accessing data from the selected resource, and
if the selected resource fails, accessing data from the next resource in the priority order.