[go: up one dir, main page]

WO2004097571A2 - Capacite de stockage elargie pour serveur de fichiers de reseau - Google Patents

Capacite de stockage elargie pour serveur de fichiers de reseau Download PDF

Info

Publication number
WO2004097571A2
WO2004097571A2 PCT/US2004/012844 US2004012844W WO2004097571A2 WO 2004097571 A2 WO2004097571 A2 WO 2004097571A2 US 2004012844 W US2004012844 W US 2004012844W WO 2004097571 A2 WO2004097571 A2 WO 2004097571A2
Authority
WO
WIPO (PCT)
Prior art keywords
file
directory
server
shadow
file server
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/US2004/012844
Other languages
English (en)
Other versions
WO2004097571A3 (fr
Inventor
Thomas K. Wong
Panagiotis Tsirigotis
Anand Iyengar
Rajeev Chawla
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
NeoPath Networks Inc
Original Assignee
NeoPath Networks Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from US10/831,376 external-priority patent/US7346664B2/en
Priority claimed from US10/831,701 external-priority patent/US7587422B2/en
Application filed by NeoPath Networks Inc filed Critical NeoPath Networks Inc
Publication of WO2004097571A2 publication Critical patent/WO2004097571A2/fr
Publication of WO2004097571A3 publication Critical patent/WO2004097571A3/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L67/00—Network arrangements or protocols for supporting network services or applications
    • H04L67/01—Protocols
    • H04L67/06—Protocols specially adapted for file transfer, e.g. file transfer protocol [FTP]
    • G—PHYSICS
    • G06—COMPUTING OR CALCULATING; COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F16/00—Information retrieval; Database structures therefor; File system structures therefor
    • G06F16/10—File systems; File servers
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L67/00—Network arrangements or protocols for supporting network services or applications
    • H04L67/01—Protocols
    • H04L67/10—Protocols in which an application is distributed across nodes in the network
    • H04L67/1095—Replication or mirroring of data, e.g. scheduling or transport for data synchronisation between network nodes
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L67/00—Network arrangements or protocols for supporting network services or applications
    • H04L67/01—Protocols
    • H04L67/10—Protocols in which an application is distributed across nodes in the network
    • H04L67/1097—Protocols in which an application is distributed across nodes in the network for distributed storage of data in networks, e.g. transport arrangements for network file system [NFS], storage area networks [SAN] or network attached storage [NAS]
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L69/00—Network arrangements, protocols or services independent of the application payload and not provided for in the other groups of this subclass
    • H04L69/30—Definitions, standards or architectural aspects of layered protocol stacks
    • H04L69/32—Architecture of open systems interconnection [OSI] 7-layer type protocol stacks, e.g. the interfaces between the data link level and the physical level
    • H04L69/322—Intralayer communication protocols among peer entities or protocol data unit [PDU] definitions
    • H04L69/329—Intralayer communication protocols among peer entities or protocol data unit [PDU] definitions in the application layer [OSI layer 7]

Definitions

  • This invention relates generally to storage networks and, more specifically, to a network device on a storage network that segregates files into separately stored directory metadata and associated data such that a file server containing the directory metadata can appear to store data beyond its storage capacity.
  • NAS Network Attached Storage
  • NAS file servers connected directly to the network provide an inexpensive and easily configurable solution for a storage network.
  • These NAS file servers are self-sufficient because they contain file systems that allow interoperability with clients running any operating system and communication using open protocols.
  • a Unix-based client can use the NFS (Network File System) protocol by Sun Microsystems, Inc. of Santa Clara, California and a Windows-based client can use CIFS (Common Internet File System) by Microsoft Corp. of Redmond, Washington to access the same files on a NAS file server.
  • NFS Network File System
  • CIFS Common Internet File System
  • SAN Storage Area Network
  • a SAN file system is part of the operating system or an application running on the client.
  • heterogeneous client operating systems may require additional copies of each file to be stored on the storage network to ensure compatibility on the SAN file server.
  • communication between clients and file servers on a SAN use proprietary protocols and thus are typically provided by a common vendor.
  • NAS file servers are preferred when price and ease of use are major considerations.
  • the benefits of NAS storage networks over SAN storage networks also have drawbacks.
  • NAS file servers there is no centralized control. Accordingly, each client must maintain communication channels between each of the NFS file servers separately. When NAS file servers are either added or removed from the storage network, each client must mount or unmount directories for the associated storage resources as appropriate. This is particularly inefficient when there are changes in hardware, but not in the particular files available on the network, such as when a failing NAS file server is swapped out for an identically configured back-up NAS file server.
  • a related drawback of decentralized control is that services must be separately purchased and installed to each NFS file server. Likewise, updates and maintenance of the services are separately provided. Furthermore, each installed service consumes data capacity that could be better used to server the main purpose of a storage network, which is to store data.
  • the network device should provide a centralized directory service using a network file server that is uninhibited from data storage responsibilities and thus can store a directory hierarchy referring to an amount of data beyond a storage capacity of the network file server.
  • the directory service should enable additional centralized services that rely on directory information.
  • a NAS Network Attached Storage
  • the directory file server provides a single directory hierarchy for the client to access data, on the order of 10 or 20 times the directory file server storage capacity, across a decentralized storage network.
  • An embodiment of a system configured according to the present invention comprises the NAS switch in communication with the client on a front-end of the storage network, and both a directory file server and one or more shadow files server on a back-end.
  • the NAS switch associates NAS file handles (e.g., CIFS file handles or NFS file handles), indicative of an object location on the storage network, with switch file handles that are independent of the object location.
  • the NAS switch then exports the switch file handles to the client.
  • the NAS switch substitutes switch file handles with appropriate NAS file handles for submission to the appropriate NAS file server.
  • the NAS switch comprises a segregation module to
  • the segregation module can store holey files, containing a range of consecutive values such as zero with negligible storage space, in the directory file server so that the holey file appears to have the same file attributes as the object without retaining its storage consumption.
  • the segregation module stores data on a shadow file server and a correlating entry into, for example, a directory server table.
  • the NAS switch performs tree hollowing to convert an existing NFS file server storing objects into a directory file server by replacing data in the objects with holey files.
  • the NAS switch comprises an association module to process client access request to existing objects.
  • the association module performs look-ups in the directory server table to find the shadow server associated with relevant directories on the directory file server.
  • the association module can then resubmit directory requests to the directory file server and data requests to the appropriate shadow file server.
  • the association module performs look-ups in a local file location cache to quickly find an explicit location of the shadow file.
  • the file location cache can store the most recently created shadow files, the most recent look-ups, the most frequently used look-ups, and the like.
  • the directory file server provides a centralized service to decentralized file servers on the storage network. Because the directory file server provides access to an extended capacity of storage, spanning across several shadow file servers of comparable capacity, the centralized service on the directory file server can be applied against this extended capacity. For example, a file locking service that preserves data integrity during multiple accesses is able to lock files from the directory file server, thereby preventing write requests to associated data on several shadow file servers.
  • FIG. 1 is a high-level block diagram illustrating a storage network system according to one embodiment of the present invention.
  • FIG. 2 is a block diagram illustrating a file server module according to one embodiment of the present invention.
  • FIG. 3 is a high-level flow chart illustrating a method of extending a storage capacity of a directory file server according to one embodiment of the present invention.
  • FIG. 4 is a flow chart illustrating a method of associating original NAS file handles with switch file handles according to one embodiment of the present invention.
  • FIG. 5 is a flow chart illustrating a method of segregating metadata in a directory file server from data in a shadow file server according to one embodiment of the present invention.
  • FIG. 6 is a flow chart illustrating a method of processing requests to access objects according to one embodiment of the present invention.
  • the present invention provides extended storage capacity for a network file server.
  • a NAS (Network Attached Storage) switch in the data path of a client and NAS file servers on the storage network, stores directory metadata separately from associated data to extend the storage capacity of a directory file server.
  • Example computing devices include enterprise servers, application servers, workstations, personal computers, network computers, network appliances, personal digital assistants, game consoles, televisions, set-top boxes, premises automation equipment, point-of-sale terminals, automobiles, and personal communications devices.
  • the program instructions can be distributed on a computer readable medium, storage volume, or the Internet. Program instructions can be in any appropriate form, such as source code, object code, or scripts.
  • FIG. 1 is a high-level block diagram illustrating a storage network system 100 according to one embodiment of the present invention.
  • the system 100 comprises a NAS switch 110 coupled to a client 140 and a storage network 175 through a network 195.
  • the storage network 175 further comprises a directory file server 120, and shadow file servers 130a-b, each also coupled in communication through the network 195.
  • the system 100 components are implemented in, for example, a personal computer with an x86-type processor executing an operating system and/or an application program, a workstation, a specialized NAS device with an optimized operating system and/or application program, a modified server blade, and the like.
  • the storage network 175 comprises a NAS storage network, using protocols such as NFS (Network File System) and CIFS (Common Internet File System).
  • NFS Network File System
  • CIFS Common Internet File System
  • the storage network 175 comprises a combination of NAS, SAN (Storage Area Network), and other types of storage networks.
  • the storage network 175 comprises a decentralized or proprietary storage network other than NAS.
  • the NAS switch 110 provides continuous transparency to the client 140 with respect to object management. Specifically, the NAS switch can off-load tasks related to physical configurations, object management, object migration, object replication, efficient storage and/or other services on the storage network 175.
  • the NAS switch 110 emulates file server processes to the client 140 and emulates client processes to the file servers 120, 130. Accordingly, the client 140 is unaware of the NAS switch 110 since the NAS switch 110 is able to redirect NAS requests intended for the file servers 120, 130 to appropriate locations on the storage network 175. Thus, the client 140 submits object requests, such as file writes and directory reads, directly to the NAS switch 110.
  • the file servers 120, 130 are unaware of the NAS switch 110 since the NAS switch 110 is able to resubmit requests, associated with NAS file handles, as if they originated from the client 140. To do so, the NAS switch 110 can use mapping, translating, bridging, packet forwarding, other network interface functionality, and other control processes to perfo ⁇ n file handle switching, thereby relieving the client 140 of the need to track changes in a file's physical location.
  • the NAS switch 110 comprises a client module 112 and a file server module 114 to facilitate communications and file handle switching.
  • the client module 112 receives exported file system directories from the file servers 120, 130 containing NAS switch handles.
  • the client module 112 maps the file system directories to an internal switch file system containing switch file handles which it sends to the client 140.
  • the client 140 traverses an exported switch file system and selects a switch file handle which it sends to the NAS switch 110 along with a requested operation.
  • the file server module 114 coordinates data segregation between the directory file server 120 and the shadow file servers 130. For a new file, the file server module 114 creates a shadow file in the shadow file server 130 and a holey file in the directory file server 120.
  • a holey file is a file that contains one or more holes.
  • a hole in a file is a range of consecutive values such as 0. Rather than storing all of the 0's, the hole is represented by just the range of zeroes, thereby using relatively little storage space.
  • the file server module 114 also maintains associations between holey and shadow files in order to reconstruct the file upon request, h one embodiment, the NAS switch 110 and the directory file server 120 are contained within a single device.
  • the file server module 114 also tracks reconfigurations resulting from migration, replication and other object relocation processes (e.g. adding or removing file server capacity) with a nested system of tables, or information otherwise linked to the switch file systems.
  • the switch file handles are static as they are persistent through the relocation processes, but the associated NAS file handles can be dynamic as they are selected depending upon an object's current location.
  • the file server module 114 maintains a directory server table, a file location cache, file handle migration table, and/or a file handle replication table corresponding to each file system that maps NAS file handles of migrated and replicated objects to locations on the storage network 175. Further embodiments of the file server module 114 are described with respect to FIG. 2.
  • the client module 112 associates 310 a NAS file handle with a switch file handle as described below with respect to FIG. 4. This enables the NAS switch 110 to act as an intermediary between the client 140 and the file servers 120, 130.
  • the client 140 submits NAS requests using switch file handles as if the NAS switch 110 were a file server 120, 130, and, in turn, the file servers 120, 130 process NAS file handles from the NAS switch 110 as if they were submitted by the client 140.
  • NAS file handles uniquely identify objects, such as a directory file server, on the file servers 120, 130, such as a directory or file, as long as that object exists.
  • NAS file handles are file server specific, and are valid only to the file servers 120, 130 that issued the file handles.
  • the process of obtaining a file handle from a file name is called a look-up.
  • the NAS file handle may be formatted according to protocols such as NFS or CIFS as discussed in further detail below, e.g., with reference to Tables 1A and IB.
  • a switch file handle identifies a directory or file object independent of location, making it persistent through file replications, migrations, and other data transfers.
  • the switch file can be a NAS file handle modified to refer to the NAS switch file system.
  • An original NAS file handle refers to an initial object location.
  • a shadow NAS file handle refers to the location of an associated shadow file.
  • a primary NAS file handle refers to the primary or preferred object location and replica or replicated NAS file handles refer to alternative or new file locations.
  • a stored NAS file handle refers to a NAS file handle, stored as an object on the file servers 120, 130, which points to an alternative file location.
  • Object access requests handled by the NAS switch 110 include, for example, directory and/or file reads, writes, creation, deletion, moving, and copying.
  • various terms are used synonymously to refer to a location of an object prior to replication (e.g., “primary”; “source”; “original”; and “first”) and various terms are used to refer to a 5 location of the same object after migration (e.g., “replica”; “destination”; “substitute”; and “second”). Further embodiments of the NAS switch 110 and methods operating therein are ) described below.
  • the client 140 accesses resources on the file servers 120, 130 by submitting a switch file handle to the NAS switch 110. To find the switch handle, the client 140 first
  • the client 140 mounts an exported switch file system containing switch file handles.
  • the client 140 looks-up an object to obtain its file handle and submits an associated request. From the perspective of the client 140, transactions are carried out by the file servers 120, 130 having object locations that do not change. Thus, the client 140 interacts with the NAS switch 110 before and after an object segregation in the same manner. A user of the client 140 can submit operations through
  • the client 140 provides access to a storage network 175 other than a NAS storage network.
  • the directory file server 120 provides a file system capable of referencing an amount of data beyond its own storage capacity.
  • the directory file server 120 comprises
  • the directory file server 120 can store an object as a holey file with a relatively small amount of data.
  • the directory file server 120 is capable of efficiently providing storage network services at a single location such as concurrency control, data encryption, and the like.
  • the directory file server
  • the system 100 comprises an back-up directory file server 120 with synchronized metadata for use during failures or overloading.
  • the directory file server 120 comprises, for example, an NFS or other decentralized file server.
  • the shadow file servers 130 store shadow files corresponding to holey files stored on the directory file server 120.
  • the shadow files comprise data such as enterprise data, records, database information, applications, and the like.
  • shadow file server 130a is dedicated to storing shadow files corresponding to one particular branch of the directory file server 120 and shadow file server 130b to a different branch.
  • shadow file server 130b is configured as a back-up or replica to shadow file server 130a.
  • the network 195 facilitates data transfers between connected hosts (e.g., 110,
  • the comiections to the network 195 may be wired and/or wireless, packet and/or circuit switched, and use network protocols such as TCP/IP (Transmission Control Protocol/Internet Protocol), IEEE (Institute of Electrical and Electronics Engineers) 802.11, IEEE 802.3 (i.e., Ethernet), ATM (Asynchronous Transfer Mode), or the like.
  • the network 195 comprises, for example, a LAN (Local Area Network), WAN (Wide Area Network), the Internet, and the like.
  • the NAS switch 110 acts as a gateway between the client 140, connected to the Internet, and the directory file server 120, and the shadow file servers 130, connected to a LAN.
  • FIG. 2 is a block diagram illustrating the file server module 114 according to one embodiment of the present invention.
  • the file server module 114 comprises a file server interface 210, a segregation module 220, and an association module 230.
  • the file server interface 210 manages client requests using the segregation module 220 for inputting separated objects to the storage network 175, and using the association module for outputting reconstructed objects to the client 140.
  • modules are merely exemplary groupings of functionality corresponding to one or many structures.
  • the file server interface 210 receives a switch file handle with a request from the client 140 which it uses to form a NAS file handle with a request to the shadow server 130. If the request involves data input, the file server interface 210 receives file handles for both the holey file and shadow file from the segregation module 220. Data input includes, for example, create, move, modify requests for an object. However, if the request involves data output, the file server interface 210 receives file handles for both the holey file and shadow file from the association module 230.
  • the segregation module 220 receives an input request from the file server interface 210 from which it forms requests to the directory and shadow servers 120, 130.
  • the segregation module 220 separates metadata and date associated with a common object.
  • the segregation module 220 further comprises a file naming module 225 to generate a name, such as by using a hash function. For example, an MD-5 hash function inputs a raw shadow name derived from a name of the directory server 120, the name of the NAS protocol (e.g., NFS or CIFS), and/or a location of the directory server 120.
  • the MD-5 hash function of the example outputs a 128-bit number.
  • the segregation module 220 then generates a file handle based on a storage location in the shadow server 130. Additionally, the segregation module 220 generates a file handle based on a storage location of the metadata in the directory server 120.
  • the association module 230 updates a directory server table stored in either the NAS switch 110 of the directory file server 120.
  • the directory server table contains a list of directories and where associated shadow files are stored.
  • the association module 230 may also update a file location cache 235.
  • the association module 230 receives an output request from the client 140 from the file server interface 210 from which it forms output requests to the directory and shadow servers 120, 130.
  • the association module 230 further comprises the file location cache 235 for faster look-ups of explicit associations. Accordingly, the file location cache 235 stores file handles for holey and shadow files based on, for example, most recently accessed, most recently stored, most frequently stored, or other prediction models to improve performance.
  • the association module 230 reconstructs objects from the separately stored metadata and data.
  • the association module 230 first checks the file location cache 235 for explicit association. If none is returned, the association module 230 checks the directory server table. Additional embodiments of the file server module 112 and methods operating therein are described below.
  • FIG. 3 is a high-level flow chart illustrating a method 300 of extending the storage capacity of a directory file server 120 according to one embodiment of the present invention.
  • the client module 114 associates 310 original NAS file handles with switch file handles as described below with respect to FIG. 4. This enables the NAS switch 110 to act as an intermediary between the client 140 and the file servers 120, 130.
  • the client 140 submits NAS requests using switch file handles as if the NAS switch 110 were a file server 120, 130, and, in turn, the file servers 120, 130 process NAS file handles from the NAS switch 110 as if they were submitted by the client 140.
  • the segregation module 220 segregates 320 metadata from data as described below with respect to FIG. 5. Because metadata associated with a file is relatively small compared to actual data, the directory file server 120 can be configured such that it appears to the client 140 to be storing an amount of data that exceeds its actual storage capacity.
  • the association module 230 processes 330 requests to access objects as described below with respect to FIG. 6. The reconstructed objects are sent directly from the storage network 175 or indirectly through the NAS switch 110 to the client 140.
  • the segregation module 220 performs a tree hollowing process to segregate objects already existing on a prior art NAS file server. Thus, rather than segregating 320 responsive to client request for inputs, the segregation module 220 initiates requests.
  • the segregation module 220 can also use error monitoring to compare a file's size before and after hollowing. If the file size and/or file data changes, then data may have been written or deleted in the interim, hi response, the data transfer process is repeated until the file size and/or file data remain constant.
  • FIG. 4 is a flow chart illustration the method of associating 310 original NAS file handles with switch file handles according to one embodiment of the present invention.
  • the NAS switch 110 mounts 410 an exported directory of file systems from the directory file server 120.
  • the exported file system organizes objects on the directory file server 120 into a hierarchy of original NAS file handles.
  • the NAS switch 110 receives exported directories from associated file servers 120 and, in turn, sends exported directories to associated clients 140.
  • the client module 112 generates 420 switch file handles independent of object locations in the primary file server 120.
  • the client module 112 organizes exported file systems from the directory file server 120 by replacing file system or tree identifiers with a switch file system number as shown below in Tables 2 A and 2B.
  • the client module 112 exports 430 the switch file system, containing the switch file handles, to the client 140 to use to look-up objects and request operations.
  • the NAS switch 110 receives the NAS request and looks-up the switch file handle to obtain an appropriate NAS file handle.
  • the file server interface 210 checks entries of nested tables maintained by the association module 230.
  • the file server interface 210 generates a NAS file handle from the switch file handle based on an object location.
  • An example of the contents of an NFS and CIFS file handle are shown in Tables 1A and IB, while an example of switch file handles or modified NFS and CIFS file handles are shown in Tables 2 A and 2B:
  • the client module 112 updates NAS file handles associated with a switch file handle. Thereby, the client 140 can access objects at new locations using the same switch file handle.
  • FIG. 5 is a flow chart illustrating the method of segregating 320 metadata from data in the directory file server according to one embodiment of the present invention.
  • the file naming module 225 generates 510 a shadow file name using a hash function.
  • the file naming module 225 obtains a raw shadow file name from a holey file.
  • the raw shadow file name can be of the form S P/Q where S is the name of the directory file server 120, P is the name of the NAS protocol, and Q is a stringified form of the file handle in NFS and is the pathname used to access the file on the directory file server 120 in CIFS.
  • a one-way hash function such as MD5 then converts the raw shadow name to a 128-bit number.
  • MD5 hash function is described in RFC (Request for Comments) 1321 promulgated by the IETF (Internet Engineering Task Force).
  • the file naming module 235 converts the 128-bit number into a hex string.
  • the segregation module 220 uses the lower order N-bits of the 128-bit number as an index to directories on the shadow file server 130.
  • the segregation module 220 creates 520 a shadow file in the shadow file server
  • the segregation module 220 looks up the directory in the directory server map. For the same file, the segregation module 220 creates 530 a holey file in the directory file server 120.
  • the holey file comprises an offset comparable to the actual file size so that it appears to have the file's size attribute.
  • the segregation module adds 220 a shadow/holey file association to the directory server table if necessary.
  • the association module 230 also adds 550 a file location to the file location cache 235.
  • FIG. 6 is a flow chart illustrating the method of processing 330 requests to access objects according to one embodiment of the present invention.
  • the association module 230 determines whether it's a directory or file object request 610. Since directory requests comprise metadata, the file server interface 210 sends them to the directory file server 120 containing the directory. For a directory creation request, the segregation module 220 sends the request to the directory server 120. In one embodiment, the file server interface 210 performs file handle switching by converting the switch file handle received from the client 140 to the NAS file handle sent to the directory file server 120. Upon successful completion, the segregation module 220 selects the next available shadow file server 130, for example, on a round-robin basis.
  • the segregation module 220 then adds the association between the directory and the selected shadow file server 130 to the directory server table. For a directory deletion request, the segregation module 220 deletes a corresponding association. Directory requests can also involve files such as file creations as described below.
  • the request may relate to a file object 630.
  • the association module 230 checks the file location cache 235 to locate the shadow file server 130 for the holey file 650. If there is a cache hit, the file server interface 210 forwards the request as indicated therein. In one embodiment, if there is a cache miss, the association module 230 determines the shadow server 130 from the directory server table and submits 670 the request to that location. In another embodiment where the shadow file severs 130 store directory server tables, the association module 230 sends the request to each shadow file server 130 to check their directory server tables. When one of the shadow file server 130 responds, the association module 230 can update the file location cache 235. Otherwise, there is an error.
  • Some requests are hybrid in that they require both directory requests and file requests.
  • the association module 230 forwards the request to the directory file server 120 to create a holey file.
  • the association module 230 checks the file location cache 235 for the associated shadow file server 130. If there is a cache hit, the association module 230 forwards the creation request as indicated. If there is a cache miss, the association module 230 resorts the directory server map.
  • the association module 230 forwards the remove request to the directory file server 120 to remove the holey file. Upon successful completion, the association module 230 forwards the remove request as indicated by the file location cache 235 or the directory server table.
  • the association module 230 forwards the request to the directory file server 120 to change the holey file's size. Upon successful completion, the association module 230 forwards the truncation request as indicated by the file location cache 235 or the directory server table.
  • the NAS switch 110 maintains several replica file servers that are synchronized with the shadow file servers 130.
  • the NAS switch 110 can replicate request to each of the appropriate replica file servers to maintain synchronicity.
  • the directory server maps in this case can contain more than one server association.
  • the file location cache 235 can store a flag indicating that a file has several copies.
  • the NAS switch 110 coordinates data migration data from one shadow file server 130 to another. Accordingly, NAS switch 110 can update the directory server table. Also, a stored file handle pointing to the new location of the data can be placed in the former location.

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Theoretical Computer Science (AREA)
  • Data Mining & Analysis (AREA)
  • Databases & Information Systems (AREA)
  • Physics & Mathematics (AREA)
  • General Engineering & Computer Science (AREA)
  • General Physics & Mathematics (AREA)
  • Computer Security & Cryptography (AREA)
  • Information Retrieval, Db Structures And Fs Structures Therefor (AREA)

Abstract

Un commutateur NAS offre une capacité de stockage élargie à un serveur de fichiers dans un réseau de stockage décentralisé tel qu'un réseau de stockage NAS (stockage relié au réseau). Le commutateur NAS se trouve dans le chemin de données d'un client à l'extrémité avant, et d'un serveur de fichiers répertoire et de serveurs de fichiers parallèles à l'extrémité arrière. Un module de tri contenu dans le commutateur NAS réplique les données émanant du serveur de fichiers répertoire vers un serveur de fichiers parallèle, puis remplace les données se trouvant dans le serveur de fichiers répertoire par des fichiers troués. Les fichiers troués, qui stockent un ensemble de valeurs consécutives telles que zéro avec un espace de stockage négligeable, préservent les attributs des données sans en retenir la consommation de stockage. Ainsi, le serveur de fichiers répertoire peut servir de hiérarchie de répertoire unique pour plusieurs serveurs de fichiers parallèles contenant des données dépassant la capacité du serveur de fichiers répertoire. Lorsque le commutateur NAS reçoit des opérations d'un client, un module d'association transfère les opérations de répertoire au serveur de fichiers répertoire et les opérations de données vers le serveur de fichiers parallèle. Le commutateur NAS offre également des services à plusieurs serveurs de fichiers parallèles à partir d'un serveur de fichiers répertoire unique.
PCT/US2004/012844 2003-04-24 2004-04-26 Capacite de stockage elargie pour serveur de fichiers de reseau Ceased WO2004097571A2 (fr)

Applications Claiming Priority (8)

Application Number Priority Date Filing Date Title
US46558003P 2003-04-24 2003-04-24
US46557903P 2003-04-24 2003-04-24
US46557803P 2003-04-24 2003-04-24
US60/465,580 2003-04-24
US60/465,578 2003-04-24
US60/465,579 2003-04-24
US10/831,376 US7346664B2 (en) 2003-04-24 2004-04-23 Transparent file migration using namespace replication
US10/831,701 US7587422B2 (en) 2003-04-24 2004-04-23 Transparent file replication using namespace replication

Publications (2)

Publication Number Publication Date
WO2004097571A2 true WO2004097571A2 (fr) 2004-11-11
WO2004097571A3 WO2004097571A3 (fr) 2005-04-28

Family

ID=34468543

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2004/012844 Ceased WO2004097571A2 (fr) 2003-04-24 2004-04-26 Capacite de stockage elargie pour serveur de fichiers de reseau

Country Status (1)

Country Link
WO (1) WO2004097571A2 (fr)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2007125313A3 (fr) * 2006-04-25 2007-12-27 Intesym Ltd Interface et routeur reseau
US7587422B2 (en) 2003-04-24 2009-09-08 Neopath Networks, Inc. Transparent file replication using namespace replication
US7720796B2 (en) 2004-04-23 2010-05-18 Neopath Networks, Inc. Directory and file mirroring for migration, snapshot, and replication
US7831641B2 (en) 2003-04-24 2010-11-09 Neopath Networks, Inc. Large file support for a network file server

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2005029251A2 (fr) 2003-09-15 2005-03-31 Neopath Networks, Inc. Autorisation de services proxy au moyen de mecanismes d'indications clients
US8195627B2 (en) 2004-04-23 2012-06-05 Neopath Networks, Inc. Storage policy monitoring for a storage network
US8190741B2 (en) 2004-04-23 2012-05-29 Neopath Networks, Inc. Customizing a namespace in a decentralized storage environment
US8832697B2 (en) 2005-06-29 2014-09-09 Cisco Technology, Inc. Parallel filesystem traversal for transparent mirroring of directories and files
US8131689B2 (en) 2005-09-30 2012-03-06 Panagiotis Tsirigotis Accumulating access frequency and file attributes for supporting policy based storage management

Non-Patent Citations (4)

* Cited by examiner, † Cited by third party
Title
'20th ieee/11th NASA goddard conference on mass storage systems and technologies' IEEE/NASA MSST 2003 07 April 2003 - 10 April 2003, PARADISE POINT RESORT, SAN DIEGO, CA, USA, *
ANDERSON ET AL.: 'Interposed request routing for scalable network storage' ACM TRANSACTIONS ON COMPUTER SYSTEMS vol. 20, no. 1, February 2002, pages 1 - 29, XP002985874 *
GOLDICK J.: 'Retry of extending networking design notes' PSC February 1995, CARNEGIE-MELLON UNIVERSITY, *
'Leveraging the benefits of the EMC CLARiiON IP4700 network file server with the Oracle8i database - ENGINEERING WHITE PAPER' EMC CORPORATION 05 March 2002, pages 1 - 24, XP002985875 *

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7587422B2 (en) 2003-04-24 2009-09-08 Neopath Networks, Inc. Transparent file replication using namespace replication
US7831641B2 (en) 2003-04-24 2010-11-09 Neopath Networks, Inc. Large file support for a network file server
US7720796B2 (en) 2004-04-23 2010-05-18 Neopath Networks, Inc. Directory and file mirroring for migration, snapshot, and replication
WO2007125313A3 (fr) * 2006-04-25 2007-12-27 Intesym Ltd Interface et routeur reseau
US8031732B2 (en) 2006-04-25 2011-10-04 Neale Bremner Smith Network interface and router with a mass storage interface device emulating a hard disk controller

Also Published As

Publication number Publication date
WO2004097571A3 (fr) 2005-04-28

Similar Documents

Publication Publication Date Title
US7072917B2 (en) Extended storage capacity for a network file server
US7346664B2 (en) Transparent file migration using namespace replication
US7720796B2 (en) Directory and file mirroring for migration, snapshot, and replication
US7587422B2 (en) Transparent file replication using namespace replication
US7831641B2 (en) Large file support for a network file server
US8190741B2 (en) Customizing a namespace in a decentralized storage environment
US8195627B2 (en) Storage policy monitoring for a storage network
US8131689B2 (en) Accumulating access frequency and file attributes for supporting policy based storage management
JP6644960B1 (ja) オブジェクトベース・ストレージでアーカイブされたデータ・コンテナをリストアする方法とシステム
US8433735B2 (en) Scalable system for partitioning and accessing metadata over multiple servers
US9967298B2 (en) Appending to files via server-side chunking and manifest manipulation
US9323758B1 (en) Efficient migration of replicated files from a file server having a file de-duplication facility
JP4154893B2 (ja) ネットワークストレージ仮想化方法
EP1618500A2 (fr) Migration transparente de fichiers par replication d'espaces de nommage
US20080281908A1 (en) Hybrid segment-oriented file server and wan accelerator
EP1805665B1 (fr) Controle de politique de stockage pour reseau de stockage
US20090024814A1 (en) Providing an administrative path for accessing a writeable master storage volume in a mirrored storage environment
CN101263494B (zh) 用于监控与存储网络中的对象相关的事务的方法和装置
WO2004097571A2 (fr) Capacite de stockage elargie pour serveur de fichiers de reseau

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A2

Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BW BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EC EE EG ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NA NI NO NZ OM PG PH PL PT RO RU SC SD SE SG SK SL SY TJ TM TN TR TT TZ UA UG US UZ VC VN YU ZA ZM ZW

AL Designated countries for regional patents

Kind code of ref document: A2

Designated state(s): GM KE LS MW MZ NA SD SL SZ TZ UG ZM ZW AM AZ BY KG KZ MD RU TJ TM AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IT LU MC NL PL PT RO SE SI SK TR BF BJ CF CG CI CM GA GN GQ GW ML MR NE SN TD TG

121 Ep: the epo has been informed by wipo that ep was designated in this application
122 Ep: pct application non-entry in european phase