Method for starting up file sharing system and file sharing device

The file sharing system of the present invention is capable of starting up a file sharing device and preventing the connection of an external storage medium to an erroneous host using information that is saved in the external storage medium. In cases where the maintenance exchange work for a NAS device is performed, the collection section collects information that is required in order to start up the NAS system section. The saving section stores the collected information in the USB memory as startup information. In cases where the NAS device is returned after the maintenance exchange is complete, the USB memory is attached to the NAS device. The setting section reads the startup information that is stored in the USB memory and sets the communication control section in accordance with an instruction from the startup control section. As a result, the NAS-OS is read from the logical volume in the storage device and the NAS system section starts up.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application relates to and claims priority from Japanese Patent Application No. 2007-150419 filed on Jun. 6, 2007, the entire disclosure of which is incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a method for starting up a file sharing system and a file sharing device.

2. Description of the Related-Art

In order to share data between a plurality of computers that are distributed across a network, a file sharing device is employed. As an initial-type of file sharing device, a file server that mounts a file sharing protocol such as a CIFS (Common Internet File System) or NFS (Network File System) on a general-purpose OS (Operating System) is known, for example. As an improved file sharing device, NAS (Network Attached Storage), which supports a plurality of file sharing protocols (CIFS, NFS, DAFS (Direct Access File System) or the like) and employs a dedicated OS which is specialized for file sharing services, is known.

In addition to NAS, SAN (Storage Area Network) storage is also known. SAN storage involves inputting and outputting data in block units to and from logical volumes that are set on a physical storage device such as a disk drive. Further, a file sharing system that involves co-operation between a NAS device and SAN storage is also known (Japanese Patent Application Laid Open No. 2005-267530).

The prior art that appears in Japanese Patent Application Laid Open No. 2005-267530 stores information that is required for the setting of the NAS system in a RAID storage area as block data. As a result, the prior art prohibits file access to the setting information and prevents the deletion of information that is required to set the NAS system as a result of an erroneous operation by the user.

In the prior art, as is presented in paragraph number [0024], a NAS disk array control section and disk enclosure are connected via an internal disk interface. In other words, because the NAS device and SAN storage are connected via an internal bus, the NAS device is able to access the disk drive relatively easily.

On the other hand, in cases where a NAS device and SAN storage are connected by using an external communication path for which authentication is required at the time of access as in the case of a file channel connection, for example, the NAS device is required to access the SAN storage by using information such as a preset WWN (World Wide Name) or LUN (Logical Unit Number). In cases where an access request that designates a predetermined LUN that is preset is issued by a device with a predetermined WWN that was preset, the SAN storage permits access.

Therefore, in cases where a NAS device is exchanged, the post-exchange NAS device is required to take over predetermined information such as a WWN or LUN or the like that has been set for the pre-exchange NAS device. This is because, in cases where predetermined information is not taken over, the post-exchange NAS device is unable to access the SAN storage.

In a normal case, the operating system (NAS-OS) whereby the NAS device provides file sharing services has a large capacity and is therefore stored in the SAN storage. The NAS device starts up the NAS system by reading the operating system from the SAN storage and executing same. Hence, because the operating system cannot be read in cases where the post-exchange NAS device is unable to access the SAN storage, the post-exchange NAS device cannot function as a NAS device.

SUMMARY OF THE INVENTION

The present invention was conceived in view of the above problem and an object thereof is to provide a method for starting up a file sharing system and file sharing device such that, in cases where a file sharing device and storage control device are connected via a communication path for which authentication is required at the time of access, the predetermined information that the file sharing device requires in order to access a logical volume in the storage control device can be set relatively easily for the file sharing device. A further object of the present invention is to provide a method for starting up a file sharing system and file sharing device such that, in cases where the file sharing device and storage control device are connected via a communication path for which authentication is required at the time of access, it is possible to prevent the setting of the predetermined information that the file sharing device requires in order to access a logical volume in the storage control device by mistake for another file sharing device. Further objects of the present invention will become evident from the following description of the embodiments.

In order to solve the above problem, in a file sharing system having at least one file sharing device and a storage control device that is connected to the file sharing device according to the present invention, (1) the storage control device comprises: (1-1) a logical volume in which an operating system that is read to the file sharing device is pre-stored; (1-2) an access control section that controls the feasibility of access to the logical volume; and (1-3) an I/O control section which, in cases where access is permitted by the access control section, reads the operating system from the logical volume and transmits same to the file sharing device in response to a request from the file sharing device, and (2) the file sharing device comprises: (2-1) an interface section for a connection to an external storage medium; (2-2) a communication control section that communicates with the storage control device via a communication path for which authentication is required at the time of access; (2-3) a collection section that collects predetermined information that is required in order to access the logical volume; (2-4) a saving section that stores the collected predetermined information in the external storage medium via the interface section; (2-5) a startup control section for starting up the operating system; (2-6) a setting section that reads the predetermined information from the external storage medium via the interface section in accordance with an instruction from the startup control section and sets the predetermined information thus read, for the communication control section; and (2-7) a file sharing section that provides file sharing services by means of the operating system that is read from the logical volume by the communication control section on the basis of the predetermined information that is set by the setting section.

According to an embodiment of the present invention, the setting section provisionally sets the predetermined information for the communication control section by storing the predetermined information in a temporary storage area that is prepared beforehand, and stores the predetermined information in the storage area in the communication control section in cases where the operating system can be read from the logical volume by the communication control section as a result of this provisional setting.

According to an embodiment of the present invention, the setting section deletes the predetermined information that is set for the communication control section in cases where the communication control section is unable to read the operating system from the logical volume.

According to an embodiment of the present invention, the setting section deletes the predetermined information that is set for the communication control section in cases where the startup of the operating system cannot be confirmed.

According to an embodiment of the present invention, the predetermined information includes identification information for uniquely specifying the file sharing device in which the predetermined information is collected; and the access control section permits the communication control section to access the logical volume only when the predetermined information used by the communication control section matches predetermined information that is set for the access control section beforehand.

According to an embodiment of the present invention, the identification information is either one or both of a serial number that is preset for the communication control section and a device number that is preset for the file sharing device.

According to an embodiment of the present invention, the file sharing device comprises an erroneous connection detection section for detecting the erroneous connection of an external storage medium storing predetermined information relating to another file sharing device.

According to an embodiment of the present invention, first medium identification information for uniquely identifying the external storage medium is preset for the external storage medium; and the erroneous connection detection section judges that an erroneous connection has been made in cases where second medium identification information that is preset and the first medium identification information that is read from the external storage medium connected to the interface section do not match one another and judges that a correct connection has been made in cases where the second medium identification information matches the first medium identification information.

According to an embodiment of the present invention, the erroneous connection detection section judges whether the communication control section is able to access the logical volume using the current setting of the communication control section, prior to the predetermined information being set for the communication control section by the setting section, and in cases where it is judged that the communication control section is able to access the logical volume using the current setting, judges that an erroneous connection has been made, and in cases where it is judged that the communication control section is unable to access the logical volume using the current setting and where the current predetermined information set for the communication control section and the predetermined information that is stored in the external storage medium do not match, judges that a correct connection has been made.

A method for starting up a file sharing device to which an external storage medium can be attached and detached, in accordance with another aspect of the present invention, a storage control device with a logical volume in which an operating system is stored and the file sharing device being connected so as to capable of two-way communication via a communication path for which authentication is required at the time of access, comprises the steps of: collecting predetermined information that is required in order to access the logical volume; storing the collected predetermined information in an external storage medium; issuing an instruction to start up the operating system; reading the predetermined information from the external storage medium in accordance with the instruction; setting the predetermined information thus read, for the communication control section; reading the operating system from the logical volume by means of the communication control section; and starting up the operating system thus read.

At least some of the respective parts and respective steps of the present invention can sometimes be implemented by a computer program. Such a computer program is stored in a storage device or distributed via a communication network, for example.

DESCRIPTION OF THE SPECIFIC EMBODIMENTS

FIG. 1is an explanatory diagram providing an overview of an embodiment of the present invention. The file sharing system shown inFIG. 1comprises, for example, a plurality of NAS devices1(1),1(2) (where no particular distinction is required hereinbelow, these are called NAS devices1), at least one storage device2, and a USB memory3. The USB memory is an example. Any kind of device can be used as long as same is a device that is capable of storing information.

Each NAS device1corresponds to a ‘file sharing device’. The respective NAS devices1sometimes constitute a cluster in order to improve reliability. The respective NAS devices1are connected so as to be capable of two-way communication to the storage device2via a communication path7which is the ‘communication path for which authentication is required at the time of access’. The communication path7is constituted as a communication path to which and from which data is input/output in block units on the basis of the fibre channel protocol, for example.

The constitution of a storage device2will be described next. The storage device2corresponds to the ‘storage control device’. The storage device2comprises, for example, a controller4, a plurality of logical volumes5, and a communication section6.

The controller4controls the operation of the storage device2. The controller4is constituted as a computer device comprising at least one microprocessor and at least one memory device or the like, for example. The controller4comprises an access control section4A and an I/O (Input/Output) control section4B.

The access control section4A judges whether access by the NAS device1to the logical volume5is permitted. The access control section4A judges, for example, the feasibility of access by the NAS device1to the logical volume5based on the LUN, WWN, target ID, and the port number of the HBA (Host Bus Adapter) as is known per the LUN security technique, for example. The I/O control section4B reads data from the logical volume5or writes data to the logical volume5on the basis of an access request from the NAS device1in cases where access by the access control section4A is permitted.

The logical volume5is a logical storage area that is provided by using physical storage areas of physical storage devices. A variety of devices capable of reading and writing data can be used as the physical storage devices, such as, for example, a hard disk device, a semiconductor memory device, an optical disk device, a magneto-optical disk device, a magnetic tape device, and a flexible disk device. Storage devices that can be used in cases where a hard disk device is used include, for example, an FC (Fibre Channel) disk, an SCSI (Small Computer System Interface) disk, a SATA disk, an ATA (AT Attachment) disk, and an SAS (Serial Attached SCSI) disk. A variety of memory devices can be used in cases where a semiconductor memory device is used as the storage device, including, for example, flash memory, Ferroelectric Random Access Memory (FeRAM), Magnetoresistive Random Access Memory (MRAM), Ovonic Unified Memory, Resistance RAM (RRAM).

The logical volume5stores an operating system (NAS-OS hereinbelow)5A for starting up the system of the NAS device1. The logical volume5is associated beforehand with a predetermined communication section6and the logical volume5can be accessed only by a predetermined NAS device1that is set beforehand. In the example shown inFIG. 1, the logical volume5on the left side ofFIG. 1is accessed by the NAS device1(1) and the logical volume5on the right side ofFIG. 1is accessed by the NAS device1(2).

The communication section6performs data communications with the communication control section1A of the NAS device1in accordance with the Fibre Channel protocol.

The constitution of the NAS device1will now be described. The NAS device1is constituted as a computer device comprising a microprocessor and a memory, for example. When we consider the function of the NAS device1, the NAS device1is constituted comprising, for example, a communication control section1A, a NAS system section1B, a collection section1C, a saving section1D, a startup control section1E, a setting section1F, a temporary storage area1G, and an interface section1H.

The communication control section1A corresponds to the ‘communication control section’. The communication control section1A performs data communications with the storage device2in accordance with the Fibre Channel protocol. The communication control section1A is constituted as a Fibre Channel communication control substrate (FC substrate) comprising HBA, for example.

The NAS system section1B corresponds to the ‘file sharing section’. The NAS system section1B is implemented as a result of the startup of the NAS-OS5A. The NAS system section1B provides file sharing services to a client device outside the scope of FIG.1which is connected to the NAS device1.

The collection section1C corresponds to the ‘collection section’. The collection section1C collects, from within the NAS device1, startup information8that is required for the NAS-OS5A to be read from the logical volume5and started up. Further, in cases where the required information exists in the storage device2, the collection section1C is also able to collect the information from the storage device2.

The saving section1D corresponds to the ‘saving section’. The saving section1D stores startup information8that is collected by the collection section1C in the USB (Universal Serial Bus) memory3. The startup control section1E corresponds to the ‘startup control section’. The startup control section1E instructs the start of the startup of the NAS-OS5A. The startup control section1E is constituted comprising a BIOS (Basic Input Output System) that has every type of driver software, for example.

The setting section1F corresponds to the ‘setting section’ The setting section1F reads startup information8that is stored in the USB memory3and thus sets the communication control section1A. The setting section1F is able to provisionally set the startup information8for the communication control section1A by storing the startup information8for the temporary storage area1G. In cases where the reading of the NAS-OS5A is successful, the setting section1F is able to formally set the startup information8for the communication control section1A. The temporary storage area1G can be set for the memory in the communication control section1A or the local memory in the NAS device1, for example.

The interface section1H corresponds to the ‘interface section’ The interface section1H serves to send and receive data to and from the USB memory3.

The USB memory3corresponds to the ‘external storage medium’. As detailed subsequently, the USB memory3pre-stores startup information8that is required in order to start up the NAS device1prior to exchanging the NAS device1. The NAS device1is re-connected to the storage device2after the deteriorated part or faulty part has been exchanged. By mounting the USB memory3in the NAS device1that has undergone maintenance work, the startup information8in the USB memory20is automatically set for the communication control section1A.

The USB memory3is an example of an external storage medium and the present invention is not limited to the USB memory3. For example, various storage media such as a hard disk drive, flash memory device, an IC card, or a memory card can be used, for example. An involatile storage medium that is portable such as the USB memory3is preferably used. However, a variety of storage media can be used irrespective of whether same afford the convenience of being portable or are involatile.

The startup information8corresponds to the ‘predetermined information required in order to access a logical volume’ and the startup information8includes, for example, the WWN, LUN and target ID of the NAS device1, the WWN of the storage device2. As is clear from the subsequent embodiments, the identification information for uniquely specifying the NAS device1and communication control section1A can also be included in the startup information8.

The operation of the file sharing system will now be described. In a normal case, the NAS device1provides file sharing services to a client device that is outsideFIG. 1by means of the NAS system section1B. In other words, the NAS system section1B accesses the storage device2in response to a file access request from the client device and inputs and outputs data to and from the storage device2.

The NAS device1is exchanged for maintenance purposes at regular or irregular intervals. In cases where a plurality of NAS devices1are operated using a cluster configuration, there is no effect on the file sharing services even when any one NAS device1is removed for maintenance. The file sharing services are provided successively to the client device by the remaining NAS device1.

The maintenance target NAS device1is removed from the file sharing system after its connection with the storage device2is released. The NAS device1is taken to a maintenance center where deteriorated parts and so forth are exchanged, for example. With the maintenance work complete, the NAS device1is shipped from the maintenance center and re-connected to the storage device2.

In order for a NAS device1which is a virtually new to function as NAS, the NAS-OS5A stored in the logical volume5in the storage device2must be read and executed.

However, in cases where part or all of the information required to access the logical volume5is lost as a result of maintenance work, the NAS device1is unable to read the NAS-OS5A from the logical volume5and the NAS system cannot be started up.

In this case, a method that involves once again manually establishing an association between the logical volume5and NAS device1may be considered. In other words, an operation that involves generating a new logical volume5, newly storing the NAS-OS5A in the logical volume5and manually associating the WWN or the like of the communication section6connected to the logical volume5and the WWN or the like of the NAS device1, for example, is required. Such manual resetting work takes time, involves user labor and is not convenient. In addition, because the work is manual work, there is also the possibility of human error.

Therefore, according to the present invention, before the maintenance target NAS device1is removed from the file sharing system, the startup information8that is required for the NAS device1to read the NAS-OS5A from the logical volume5and start up the NAS-OS5A is saved to the USB memory3.

In cases where the NAS device1that has undergone maintenance is returned, the work for the physical connection between the NAS device1and the storage device2is then performed, whereupon USB memory3is connected to the NAS device1. The startup information8that is stored in the USB memory3is set for the communication control section1A by the setting section1F on the basis of an instruction from the startup control section1E.

The communication control section1A is able to access the logical volume5that was connected prior to the maintenance work and read the NAS-OS5A that is stored in the logical volume5. As a result, the NAS device1rapidly executes a system startup to provide the file sharing services.

The details will be clearly provided in the subsequent embodiments. However, the possibility exists for the USB memory3to be mounted in another NAS device1. In particular, in cases where a cluster is constituted by a plurality of NAS devices1and where maintenance work is performed at the same time for a plurality of NAS devices1in the same cluster, there is the risk that the USB memory3that stores startup information8relating to a certain NAS device1will be mounted in another NAS device1by mistake.

Therefore, according to the present invention, either or both of the storage device2or NAS device1comprises a device for preventing an erroneous connection of the USB memory3, for example. For example, by judging the feasibility of access by the storage device2by using a serial number for uniquely identifying the device number that uniquely identifies the NAS device1and the communication control section1A, a situation where the startup information8is overwritten to an unrelated NAS device1by mistake can be prevented.

In this embodiment that is constituted in this manner, the maintenance work of the NAS device1can be performed relatively rapidly and accurately and user convenience improves. In addition, according to this embodiment, a situation where the startup information8relating to one NAS device1is stored by mistake in another NAS device1can of course be prevented, the reliability during the maintenance exchange work can be increased, and user convenience can be improved. Embodiments of the present invention will be described in detail hereinbelow.

First Embodiment

FIG. 2is a block diagram of the hardware constitution of the file sharing system. The file sharing system is constituted comprising a plurality of NAS devices10, at least one storage device100, and a USB memory20, for example. The respective NAS devices10and the storage device100are connected so as to be capable of two-way communication via a switch30. A management terminal40can be connected to the storage device100. Further, the management server outsideFIG. 2, the storage device100, and the respective NAS devices10can also be connected so as to be capable of two-way communication via a LAN (Local Area Network).

The relationship ofFIG. 2with respect toFIG. 1will now be described. The NAS device10corresponds to the NAS device1inFIG. 1, the storage device100corresponds to the storage device2inFIG. 1, and the USB memory20corresponds to the USB memory3inFIG. 1. The communication path CN1corresponds to the communication path7inFIG. 1, the communication interface111A corresponds to the communication section6inFIG. 1, and the logical volume122corresponds to the logical volume5inFIG. 1. The HBA13corresponds to the communication control section1A inFIG. 1, the USB I/F15corresponds to the interface section1H inFIG. 1, and the startup information50corresponds to the startup information8inFIG. 1.

The access control section4A and I/O control section4B shown inFIG. 1are implemented by a program that is executed by a microprocessor in a controller110. The respective functions1B to1F in the NAS device1shown inFIG. 1are implemented as a result of the microprocessor11of the NAS device10executing a predetermined program. The temporary storage area1G inFIG. 1is provided by using the memory in HBA13or the memory12in the NAS device10.

The constitution of the NAS device10will now be described. The NAS device10comprises, for example, a microprocessor (CPU inFIG. 2)11, the memory12, the HBA13, the user interface (UI inFIG. 2)14, the USB I/F15, and the internal bus16. The memory12stores, for example, a USB driver200, an FC driver201, a SAN boot driver202, and an NAS-OS203.

The USB driver200is software for inputting and outputting data to and from the USB memory20. The FC driver201is software for performing data communications on the basis of the Fibre Channel protocol. The SAN boot driver202is software for reading the NAS-OS203from the logical volume122and starting up the NAS-OS203. The NAS-OS203is software for providing the client device outsideFIG. 2with file sharing services.

The USB memory20is detachably attached to the NAS device10. The USB memory20stores startup information50that is collected from the NAS device10. The NAS device10is able to set the startup information50stored in the USB memory20for the HBA13, as will be described subsequently.

The switch30is constituted as a Fibre Channel switch, for example. By using the switch30, a plurality of NAS devices10can be connected to the storage device100.

The management terminal40changes the constitution of the storage device100, acquires every kind of information from the storage device100, and displays this information on the terminal display.

The constitution of the storage device100will now be described. The storage devices100can be broadly classified into the controller110and the storage device mount section (‘HDU’ hereinbelow)120. The controller110controls the operation of the storage device100. The controller110is constituted comprising, for example, a plurality of channel adapters (‘CHA’ hereinbelow)111, a plurality of disk adapters (only one is shown inFIG. 2, which appears as ‘DKA’ hereinbelow)112, a shared memory (‘SM’ hereinbelow)113, a cache memory (‘CM’ hereinbelow)114, a connection control section115, and a service processor (‘SVP’ hereinbelow)116.

The CHA111is a computer device for performing FCP (Fibre Channel Protocol)-based communications, for example. The CHA111are constituted by one or a plurality of substrates on which a microprocessor and memory and so forth are mounted, for example, and this memory stores a program for analyzing and executing FCP-based commands. The CHA111comprise at least one fibre channel interface (displayed as ‘FC-I/F’ inFIG. 2)111A. The fibre channel interfaces111A have their WWN preset. By specifying the WWN and target IDs, the CHA111are able to communicate with the NAS devices10.

The DKA112exchanges data with disk drives121that the HDU120comprises. The DKA112is constituted as a computer device comprising a microprocessor and a memory and so forth as per the CHA111. InFIG. 2, only one DKA112is shown for the sake of convenience but, in actuality, a plurality of DKA112are provided.

The DKA112is connected to the respective disk drives121in the HDU120via a fiber channel. The DKA112writes data that are received by the respective CHA111and stored in the cache memory114to predetermined addresses in predetermined disk drives121. The DKA112reads data that are requested from the respective CHA111from predetermined disk drives121and stores the data in the cache memory114.

The DKA112converts a logical address into a physical address. A logical address is an address indicating a block position in a logical volume and is known as an LBA (Logical Block Address). A physical address is an address indicating a write position in the disk drive121. The DKA112performs data access corresponding with a RAID configuration in cases where the disk drives121are managed per the RAID system. For example, the DKA112writes the same data to a plurality of disk drives121(RAID1) or executes a parity calculation to distribute and write data and parities to a plurality of disk drives121(RAID5 and so forth).

The shared memory113is a memory for storing every kind of management information and control information and so forth that is employed in order to control the operation of the storage device100. The cache memory114is a memory for storing data that are received by the CHA111or data that have been read from the disk drives121by the DKA112.

Any one or a plurality of disk drives121may be used as a cache disk. As perFIG. 2, the cache memory114and shared memory113may also each be constituted as separate memory. Alternatively, a partial storage area of the same memory may be used as a cache area while another storage area may be used as a control area.

The connection control section115mutually connects the CHA111, DKA112, cache memory114, and shared memory113. The connection control section115is constituted as a loss path switch that performs data transmission by means of a high-speed switching operation, for example.

The SVP116is connected to each CHA111via a communication network such as a LAN, for example. The SVP116is able to access the DKA112, cache memory114, and shared memory113via the CHA111, for example. The SVP116collects information relating to every kind of state in the storage device100and supplies the information to the management terminal40. The user is able to learn of every kind of state of the storage device100via the screen of the management terminal40.

The user is able to establish an access path between the NAS device10and logical volume, for example, via the SVP116from the management terminal40, generate a logical volume122, and delete a logical volume122.

The HDU120comprises a plurality of disk drives121. Although a disk drive is cited by way of example in this specification, the present invention is not limited to a hard disk drive. For example, various storage devices and equivalents thereof such as semiconductor memory drives (including flash memory devices) and holographic memory and so forth can be used. Further, different kinds of disks can also be mixed within the HDU120such as FC disks, SATA disks, and ATA disks, for example.

One RAID group (also called a ‘parity group’) is formed by a plurality of disk drives121. A RAID group is obtained by virtualizing a physical storage area of respective disk drives121in accordance with the RAID level and can be called a physical storage device. The physical storage area of the RAID group is a predetermined size or an optional size and can be provided by one or a plurality of logical volumes122. The logical volume122is displayed as ‘LU’ inFIG. 2. The logical volume122can be called a logical storage device. In this embodiment, a NAS-OS is pre-stored in a predetermined logical volume122that is used by the NAS device10. File data that are employed by the NAS device10are also stored in the predetermined logical volume122.

The data I/O operation of the storage device100will now be described in simple terms. A read command that is issued by the NAS device10is received by the CHA111. The CHA111stores the read command in the shared memory113.

The DKA112references the shared memory113as occasion calls. Upon finding an unprocessed read command, the DKA112accesses the disk drive121constituting the logical volume122designated as the read destination and reads the requested data. The DKA112performs physical address and logical address conversion processing and stores the data read from the disk drive121in the cache memory114. The CHA111transmits the data that are stored in the cache memory114to the NAS device10. In cases where the data requested by the NAS device10are already stored in the cache memory114, the CHA111transmits the data stored in the cache memory114to the NAS device10.

The write command issued by the NAS device10is received by the CHA111as in the case of a read command. The CHA111stores the write data transmitted by the NAS device10to the cache memory114. The DKA112stores the write data stored in the cache memory114in the disk drive121constituting the logical volume122designated as the write destination.

Further, the constitution may also be such that the NAS device10is notified that processing is complete at the point where the write data are stored in the cache memory114, or the constitution may be such that the NAS device10is notified that processing is complete after write data are written to the disk drive121.

FIG. 3is an explanatory diagram showing an example of a LUN security management table T1that constitutes at least part of the ‘access control section’. ‘LUN security’ is a technology that permits access to the logical volume122for only a preset NAS device10.

The management table T1can comprise a LUN item C1, target ID item C2, a WWN item C3, and an access control item C4, for example. Other items may also be provided. ‘WWN’ indicates the WWN that is set for the HBA13of the NAS device10. The ‘target ID’ is information for specifying the communication port which is the target port. ‘Access control’ is information controlling the type of access. Examples of access control can include the ‘readable and writable’ and ‘read only’.

Thus, the feasibility of access to the logical volume122that is associated with the LUN depending on whether the combination of the LUN, target ID, and WWN is correct is judged. As shown in the lower half ofFIG. 3, even when there is a match between the LUN and target ID, for example, in cases where the WWN of the source of the access request (WWN2or WWN3) differs from the WWN (WWN1) registered in the management table T1, access is denied.

FIG. 4is an explanatory diagram that schematically shows the constitution of the startup information50. The startup information50is constituted comprising, for example, the WWN51of the NAS device10, the HBA information52, the information53of the LUN and the WWN of the storage device100, and the information54of the target ID.

The HBA information52is information indicating which communication port among the plurality of communication ports that the HBA13comprises is used. Further, although the FC communication control substrate is simplified as HBA13for the sake of convenience, in reality, a plurality of HBA can be installed in the FC communication control substrate and each HBA can comprise a plurality of communication ports.

Further,FIG. 4shows that the WWN information51and HBA information52of the NAS device10are collected from the HBA13and the information53of the LUN and WWN of the storage device100and the target ID information54are collected from the shared memory113. However, in reality, these information items51to54can be collected from the HBA13. InFIG. 4, the original locations of each information item are shown. The WWN set for the NAS device10is sometimes displayed as WWN (NAS) and the WWN set for the storage device100is sometimes displayed as WWN (SAN) hereinbelow.

FIG. 5is a flowchart showing the processing and so forth for saving the startup information50to the USB memory20. In cases where maintenance work for the NAS device10is carried out, the user instructs the removal of the NAS device10via the user interface section14of the NAS device10. The NAS device10is able to judge that same is to be exchanged for maintenance work according to the instruction from the user (S10).

When an instruction to exchange the NAS device10is issued (S10: YES), the NAS device10collects WWN (NAS) and HBA information and stores same in the USB memory20(S11). Thereafter, the NAS device10collects the LUN, target ID and WWN (SAN) and stores same in the USB memory20(S12). Further, although this process is described as being divided into two steps which are S11and S12for the sake of convenience, the respective information items51to54shown inFIG. 4can be stored in the USB memory20using a single step.

If the startup information50is stored in the USB memory20, notification to the effect that the NAS device10can be removed is sent to the user via the user interface14(S13). Upon checking the notification, the user halts the supply of power to the NAS device10, cancels the connection between the storage device100and NAS device10, and removes the NAS device10from the file sharing system.

The removed NAS device10is sent to the maintenance center. Upon arrival of the NAS device10at the maintenance center (S20), the part which is the exchange target among the constituent parts of the NAS device10is specified (S21). At the maintenance center, the specified part is exchanged for a new part (S22), and various settings are made (S23). The maintenance center examines whether the NAS device10is working normally (S24) and, when the examination is a success, the NAS device10is shipped to the user (S25). Further, S20to S25above are a general outline of the procedure for the maintenance work at the maintenance center and do not constitute a procedure that is executed by a computer device. However, at least some of the maintenance work that is carried out at the maintenance center can sometimes be automatically or semi-automatically performed by using a computer device.

FIG. 6is a flowchart showing the processing to connect a NAS device10that had undergone maintenance work to the file sharing system and start up the NAS device10. The respective flowcharts shown inFIG. 6provide an overview of the respective processing within the range required to understand and implement the present invention and sometimes differ from those of an actual computer program. A person skilled in the art is surely able to switch the numbering of the illustrated steps, delete some steps, and add new steps.

First, the storage device100is started up after physically connecting the NAS device10and storage device100(S30). Thereafter, power is supplied to the NAS device10and the respective drivers200to202are started up (S31).

The NAS device10(USB driver200) reads the startup information50from the USB memory20and stores same in the temporary storage area (S32). The NAS device10provisionally sets the startup information50read from the USB memory20for the HBA13(S33). The NAS device10(FC driver201) attempts access to the storage device100based on the provisionally set WWN and so forth (S34). Here, a read command is issued by the NAS device10, for example.

When an access request is issued by the NAS device10, the storage device100uses the management table T1to execute LUN security processing (S35). The NAS device10judges whether to access the NAS-OS (S36). In other words, the NAS device10judges whether a logical volume122storing the NAS-OS has been mounted in the NAS device10.

In cases where access to the NAS-OS has not been possible (S36: NO), the NAS device10re-attempts access to the NAS-OS and adds one to the retry count RC (S37). In cases where the NAS device10has been unable to access the NAS-OS even though the retry count RC has reached a predetermined count Th1that is preset (S38: YES), the NAS device10deletes the startup information50stored in the temporary storage area (S39). The NAS device10notifies the user of the error via the user interface14(S40).

A case where it has not been possible to access the NAS-OS with the provisionally set startup information50may be considered to be a case where the USB memory20is mounted in NAS device10other than the NAS device10that has undergone maintenance work. In other words, this is because a NAS device10other than the re-startup target NAS device10is currently operating normally and it is not possible to start up the NAS-OS by mounting a different logical volume122. At that point, in S40, an error message such as ‘Please check where the USB memory is mounted’, for example, is displayed.

In contrast, in cases where it has been possible to access the NAS-OS with the provisionally set startup information50(S36: YES), the NAS device10(SAN boot driver202) reads the NAS-OS from the mounted logical volume122(S41). The NAS device10judges whether the NAS-OS has started up normally (S42). In cases where the NAS-OS has started up normally (S42: YES), the NAS device10stores the startup information50that has been read from the USB memory20in the HBA13(S43). In other words, the NAS device10overwrites the startup information50read from the USB memory20with information that is stored in the HBA13. The overwriting of startup information is thus complete.

Removal of the USB memory20from the NAS device10by way of an erroneous operation by the user in the course of the startup of the NAS-OS may also be considered. Here, in cases where the NAS-OS does not start up normally (S42: NO), the NAS device10re-attempts the reading and startup of the NAS-OS only a predetermined number of times Th1(S44, S45). In cases where the retry count RC reaches Th1(S45: YES), the NAS device10deletes the provisionally set startup information50(S46) and notifies the user of the error (S47).

In S47, an error message such as ‘The start-up of the NAS-OS has failed. Please check the host of the USB memory’ for example, can be displayed, for example.

This embodiment with this constitution affords the following effects. In this embodiment, the startup information50required to start up the NAS device10is saved to the USB memory20prior to the maintenance work for the NAS device10. Further, in this embodiment, by mounting the USB memory20in a NAS device10that has undergone maintenance work, the information of the WWN or the like can be set automatically for the NAS device10, the NAS-OS can be read from the logical volume122, and the NAS-OS can thus be started up. Therefore, there is no need for the user to manually perform various settings and the maintenance work for the NAS device10and the re-startup thereof can be carried out easily, whereby user convenience improves.

According to this embodiment, in cases where the startup of the NAS-OS is attempted using the startup information50that is stored in the temporary storage area and the NAS-OS starts up normally, the startup information50in the HBA13is overwritten with the startup information50in the USB memory20. The NAS device10can therefore be started up more stably.

According to this embodiment, even in cases where the USB memory20is mounted in another NAS device10, the NAS device10is unable to read and start up the NAS-OS. Hence, user convenience and the stability of the file sharing system improve.

Second Embodiment

The second embodiment of the present invention will now be described based onFIGS. 7 and 8. The respective embodiments described hereinbelow correspond to modified examples of the first embodiment. In this embodiment, prior to attempting access to the NAS-OS by using the startup information50in the USB memory20, it is diagnosed whether the USB memory20is connected to a NAS device10other than the NAS device10which is to be connected originally.

FIG. 7is a flowchart showing, in simplified form, processing to startup the NAS device10according to this embodiment. The storage device100is started up after physically connecting the NAS device10that has undergone maintenance work and the storage device100(S50). Thereafter, the respective drivers200to202of the NAS device10are started up (S51) and then the diagnostic processing is executed (S52). The details of the diagnostic processing will be described subsequently in conjunction withFIG. 8.

As a result of the diagnostic processing of S52, in cases where it is judged that the host of the USB memory20is correct (S53: YES), the NAS device10stores the startup information50read from the USB memory20in the HBA13(S54) and accesses the logical volume122in the storage device100(S55). If an access request is issued by the NAS device10, the storage device100executes LUN security processing (S56). The NAS device10reads the NAS-OS (S57) and judges whether the NAS-OS has started up normally (S58).

In cases where the NAS-OS has started up normally (S58: YES), this processing ends. In cases where the NAS-OS has not started up normally (S58: NO), the NAS device10notifies the user of the error (S59). When it is judged that the host is incorrect (S53: NO), this processing ends. Thereupon, the user can be notified of the error.

In cases where, as a result of the diagnosis, it is judged that the host of the USB memory20is correct (S53: YES), the information in the HBA13is not directly overwritten by the startup information50in the USB memory20(S54) and, as per the first embodiment, the constitution may also be such that the information in the HBA13is overwritten after it has been confirmed that the NAS-OS has started up normally (S58: YES). In addition, the retries of a predetermined count mentioned in the first embodiment can also be executed by this embodiment.

FIG. 8is a flowchart showing the details of the diagnostic processing shown in S52inFIG. 7. First, the NAS device10re-attempts access to the NAS-OS with the startup information50that is currently set for the HBA13(S520) and judges whether access has been made (S521).

In cases where the NAS-OS has been accessed with the current settings (S521: YES), it can be considered that the USB memory20is connected to a NAS device10other than the predetermined NAS device10. This is because the NAS-OS can be accessed without the need to use the startup information50in the USB memory20. Therefore, the NAS device10judges that the host of the USB memory20is erroneous (S522).

In cases where it has not been possible to access the NAS-OS by using the startup information50that is currently set for the HBA13(S521: NO), the NAS device10judges whether the WWN stored in the USB memory20and the WWN stored in the HBA13do not match (S523).

In cases where the WWN stored in the USB memory20and the WWN currently set for the HBA13do not match (S523: YES), the NAS device10judges that the host of the USB memory20is correct (S524). In contrast, in cases where the WWN currently set for the HBA13and the WWN stored in the USB memory20match (S524: YES), the NAS device10notifies the user of the error (S525). This embodiment with this constitution affords the same effects as those of the first embodiment.

Third Embodiment

The third embodiment will now be described on the basis ofFIGS. 9 and 10. In this embodiment, the feasibility of access to the NAS-OS is judged by using a serial number for uniquely identifying the HBA13rather than just LUN security processing that is executed by the storage device100.

The significance of this embodiment will first be described. For the sake of comprehension, let the NAS device that has undergone maintenance work be NAS device10(1) and the other NAS device be NAS device10(2). Further, let the startup information of the NAS device10(1) be startup information50(1) and the USB memory that stores the startup information50(1) be USB memory20(1). Likewise, let the startup information of the NAS device10(2) be startup information50(2) and the USB memory that stores the startup information50(2) be USB memory20(2).

As mentioned in the first embodiment, in cases where the NAS device10(1) is started up again, the USB memory20(1) may be mounted on the NAS device10(1). If the user mounts the USB memory20(1) on the NAS device10(2) by mistake, a logical volume122is already mounted on the NAS device10(2) and, therefore, the NAS-OS used for the NAS device10(1) cannot be read and started up.

However, if the user mounts the USB memory20(2) on the NAS device10(1) by mistake, there is a risk that startup information50(2) will be set for the NAS device10(1). In this case, there can be no distinction between the NAS device10(1) and NAS device10(2) from the perspective of the storage device100. This is because both the NAS devices10(1) and10(2) have the same startup information50(2).

Therefore, according to this embodiment, the NAS device10(1) and NAS device10(2) are distinguished using characteristic identification information that is set for the HBA13and access by a device other than the NAS device10(2) that was originally capable of access is denied.

FIG. 9is an explanatory diagram showing an example of the management table T1of this embodiment. The management table T1has a serial number item C5added thereto. A serial number is identification information for uniquely specifying the HBA13within the file sharing system. There is no need for consecutive numbers as long as the information is information that allows the HBA13to be uniquely specified.

The storage device100acquires the serial number of the HBA13from the NAS device10prior to the exchange of the NAS device10and pre-stores the serial number in the management table T1. Further, once the NAS device10is exchanged, the serial number of the HBA13can be transmitted from the NAS device10to the storage device100and the accessibility based on the serial number can be judged by the storage device100.

FIG. 10is a flowchart showing processing to start up the NAS device10according to this embodiment. The flowchart comprises the steps S30to S47that are common to the flowchart shown inFIG. 6. In this embodiment, S70and S71have been newly added. Therefore, a description of the common steps is omitted and the focus of the description is on the steps which are characteristic of this embodiment.

In cases where the NAS-OS has been accessed with the startup information50stored in the temporary storage area (S36: YES), the storage device100acquires the serial number of the HBA13from the NAS device10that has achieved access and judges whether the serial number of the HBA13thus acquired and the serial number that is stored in management table T1match one another (S70).

In cases where there is indeed a match between the serial number registered in the management table T1beforehand and the serial number acquired from the NAS device10that achieved access in S36(S70: YES), this means that the USB memory20is connected to the correct NAS device10. Therefore, S41and the subsequent steps are executed.

When where there is no match between the two serial numbers (S70: NO), this means that the USB memory20is connected to a NAS device10that is different from the NAS device10that was originally arranged. Therefore, the NAS device10notifies the user of the error (S71).

This embodiment with this constitution affords the same effects as those of the first embodiment. In addition, according to this embodiment, in cases where the WWN or the like match and access to the NAS-OS is successful, the storage device100also judges the feasibility of access based on the serial number. In other words, in this embodiment, a first accessibility judgment by way of LUN security processing and a second accessibility judgment based on the serial number are each executed. Hence, according to this embodiment, even in cases where another USB memory20has been mounted on the NAS device10to be exchanged for maintenance by mistake, the NAS device10to be exchanged for maintenance is naturally able to prevent access to another logical volume for which access is not permitted. As a result, user convenience and reliability of the maintenance exchange work improve further.

Fourth Embodiment

A fourth embodiment will now be described based onFIGS. 11 and 12. In this embodiment, the device numbers of the NAS device10are used in place of the serial numbers of the HBA13used in the third embodiment.FIG. 11is an explanatory diagram of an example of the management table T1according to this embodiment. The management table T1has a sixth item C6for managing the device numbers of the NAS devices10added thereto. The device number is identification information for uniquely specifying the NAS devices10within the file sharing system.

FIG. 12is a flowchart showing the startup processing of the NAS device10. Instead of the S70that was described in the third embodiment, it is judged in S80of this embodiment whether the device number acquired from the NAS device10that achieved access and the serial number that is registered in the management table T1match one another (S80). This embodiment with this constitution also affords the same effects as those of the first and third embodiments.

Fifth Embodiment

A fifth embodiment will now be described based onFIGS. 13 and 14. In this embodiment, the serial number of the HBA13is uniquely stored when the startup information50is stored in the USB memory20. Further, in cases where the USB memory20is attached to the NAS device10, the serial number in the USB memory20and the serial number of the HBA13in the NAS device10are compared and it is confirmed whether the USB memory20is connected to the correct host. In other words, in this embodiment, the serial number of the HBA13is used as information for representing the relationship between the USB memory20and NAS device10.

FIG. 13is a flowchart showing the error connection prevention processing of the USB memory20and the processing to save the startup information. The processing will be described starting with the saving processing. When an exchange contract for the NAS device10is in place (S10: YES), the NAS device10stores the serial number of the HBA13in the USB memory20in addition to the startup information50such as the WWN and target (S11A, S12).

The erroneous connection prevention processing for the USB memory20will now be described. If the USB memory20is attached to the NAS device10(S90), the NAS device10reads the serial number of the HBA13that is stored in the USB memory20(S91) and compares the serial number thus read with the serial number of the HBA13in the NAS device10(S92).

In cases where the two serial numbers match one another (S93: YES), the NAS device10judges that the host of the USB memory20is correct (S94). In contrast, in cases where the two serial numbers do not match one another (S93: NO), the NAS device10judges that the host of the USB memory20is erroneous (S95). In the case of an erroneous connection, the NAS device10is able to notify the user of the error. This embodiment with this constitution affords the same effects as those of the first embodiment.

Sixth Embodiment

The sixth embodiment will be described based onFIG. 14. According to this embodiment, the ‘serial number and device number’ are used in place of the serial number mentioned in the fifth embodiment. That is, in this embodiment, a combination of a serial number and device number is used as information representing the relationship between the USB memory20and NAS device10.

FIG. 14is a flowchart showing the saving processing and the erroneous connection prevention processing of the USB memory20according to this embodiment. The NAS device10stores the serial number and device number in the USB memory20when the startup information50is stored in the USB memory20(S11B).

When the USB memory20is attached to the NAS device10(S90), the NAS device10reads the serial number and device number stored in the USB memory20(S91B) and compares the serial number thus read with the serial number and device number in the NAS device10(S92B).

In cases where the two serial numbers match one another and the two device numbers match one another (S93B: YES), the NAS device10judges that the host of the USB memory20is correct (S94). In contrast, in a case where the two serial numbers do not match one another or where the two device numbers do not match one another (S93B: NO), the NAS device10judges that the host of the USB memory20is erroneous (S95). In the case of an erroneous connection, the NAS device10is able to notify the user of the error. Thus, this embodiment with this constitution affords the same effects as those of the first embodiment.

Seventh Embodiment

A seventh embodiment will now be described based onFIGS. 15and16. According to this embodiment, it is judged whether the relationship between the NAS device10and USB memory20is correct by using an ID tag21that is provided in the USB memory20.

FIG. 15is an explanatory diagram of the constitution of the file sharing system according to this embodiment. The ID tag21is provided in the USB memory20of this embodiment. The NAS device10is provided with a tag reader17. In addition, an ID204which is the same as the ID stored in the ID tag21is pre-stored in the memory12of the NAS device10.

The tag reader17transmits a wireless signal at regular intervals or when the USB memory20and interface15are connected. The ID tag is constituted comprising, for example, a memory where IDs are stored, a receiver circuit, a control circuit that operates by taking the induced electromotive force obtained by the receiver circuit as its power source, and a transmitter circuit. Upon receipt of radio waves emitted by the tag reader17, the ID tag21generates a response signal comprising an ID and transmits the response signal.

FIG. 16is a flowchart showing the erroneous connection prevention processing of the USB memory20. If the USB memory20is connected to the interface15(S90C), the NAS device10reads the ID that was stored in the ID tag21by the tag reader17(S91C). The NAS device10compares the ID204stored in the memory12with the ID read from the ID tag21(S92C) and judges whether the two IDs match one another (S93C).

In cases where the two IDs match (S93C: YES), the NAS device10judges that the host of the USB memory20is correct (S94). In cases where the two IDs do not match one another (S93C: NO), the NAS device10judges that the host of the USB memory20is erroneous (S95). This embodiment with this constitution also affords the same effects as those of the first embodiment.

The present invention is not limited to that above embodiments. A person skilled in the art is able to make a variety of additions or modifications or the like within the scope of the present invention.