JP4130859B2 - External storage device - Google Patents

Description

BACKGROUND OF THE INVENTION
The present invention relates to an external storage device with low operation cost. In particular, the present invention relates to an external storage device that provides a plurality of logical units and uses the means for batch writing inside the device to write the same contents in a plurality of storage areas.
[Prior art]
(1) Writing to external storage by users In an environment where multiple users operate separate computers, it is necessary to write operating systems (OS), applications, user data, etc. to the external storage of each computer. .
With reference to FIG. 1, installation of an OS or application to a plurality of external memories will be described. In FIG. 1, 101, 111, and 121 are users of computers 102, 112, and 122, respectively, and 103, 113, and 123 are external storages connected to the computer. 104, 114, and 124 are contents stored in the external storage.
When installing an OS or application in the external memory, each user operates the computer by himself and writes it in the external memory to be used. For example, the content 104 is installed in the external storage 103 when the user 101 operates the computer 102. Similarly, the content 114 is installed in the external storage 113 by the user 111, and the content 124 is installed in the external storage 123 by the user 121.
(2) Batch writing to two external storages using RAID level 1 On the other hand, the method using RAID (Redundant Arrays of Inexpensive Disks) level 1 is known as a method of writing the same contents to multiple external storages in batch. It has been. Regarding RAID, see "A Case for Redundant Arrays of Inexpensive Disks (RAID)"; In Proc. ACM SIGMOD Conf., Jun., 1988.
The RAID level 1 will be described with reference to FIG. In FIG. 2, reference numeral 203 denotes an external storage device connected to a computer 202, which includes storage media 205 and 206 and a write duplexing means 204. When the user 201 operates the computer 202 to write to the external storage, the same contents 207 and 208 are written to the storage media 205 and 206 by the duplexing means 204 in the external storage device, respectively. External storage duplicated at RAID level 1 is recognized as one external storage by the computer.
[Problems to be solved by the invention]
In the prior art, since each user updates the external memory by himself, the number of users who operate the computer increases as the number of external memories to be written increases. In particular, when the contents written to the external storage by each user such as OS and application are common, there is a problem that the operating cost of the system increases because the same contents are individually written by many users. The operation cost refers to the entire cost including the labor cost necessary for system operation, and is represented by the product of the number of persons involved in the operation and the work time.
Furthermore, when the number of users is large, there is a difference in the proficiency level of each user for the operation. A user with a low level of proficiency spends a long time to complete the operation or requires a system administrator, which causes a higher operation cost.
On the other hand, in the method using RAID level 1, data can be written to two storage media with a single write operation. However, since the two storage media are recognized as one external storage by the computer, the memory written in duplicate is stored. There is a problem that it cannot be applied to a usage form in which the contents are used by different users.
An object of the present invention is to reduce operation costs by allowing a single operator to collectively write to a plurality of external memories.
It is another object of the present invention to provide a method for collectively writing to external storages of a plurality of computers.
[Means for Solving the Problems]
According to the present invention, when the same contents are installed in a plurality of external memories, the same contents are collectively written in the plurality of logical units by designating a group consisting of a plurality of logical units as an installation destination. The batch writing means of the external storage device determines a logical unit to be written with reference to a group definition composed of a plurality of logical units stored as a batch writing unit, and writes the same contents to each. Thereby, it is possible to write to a plurality of logical units all at once with a single write request. At that time, the access control means restricts access to the logical unit based on the access authority defined and stored in units of logical units. Thereby, it is possible to prevent reference / update of another access to the logical unit being written.
The means for controlling rewriting of the access authority definition and the means for controlling rewriting of the group definition of the logical unit rewrite the access authority definition and the group definition of the logical unit, respectively. Thereby, the administrator can control access to an arbitrary logical unit and define a group of logical units. Further, the installer sends data to be written to the batch writing means with the specified group of logical units as a write destination. As a result, a single administrator can perform batch installation on a plurality of designated logical units.
DETAILED DESCRIPTION OF THE INVENTION
First embodiment (Batch writing to external storage of diskless computer connected by Fiber Channel)
A first embodiment will be described. The present embodiment is an example in which the present invention is applied when an operating system (OS) is installed in an external storage of a computer in a system in which a plurality of computers are connected to an external storage device through a fiber channel.
(1) Explanation of Configuration FIG. 3 shows the overall configuration of this embodiment, and FIG. 4 shows the details of the disk array used in FIG. FIG. 5 shows the configuration of a batch write group definition table used in the disk array.
In FIG. 3, reference numerals 301 to 331 denote computers that do not incorporate a large-capacity external storage device such as a hard disk. The computers 301 to 331 read the OS stored in the disk array 360 by the boot-up means 302 to 332 and start it up. The disk array 360 provides external storage to the computers 301-331. The fiber channel connection means 350 is a hub or a switch, for example, and provides a data communication path between the disk array 360 and the computers 301 to 331 and the disk array management terminal 370 connected by the fiber channels 341 to 345. The disk array management terminal 370 communicates control information from the disk array control means 374 via the communication means 372, and controls the operation of the disk array 360. As a communication path between the communication unit 372 and the disk array 360, for example, RS232C or Ethernet can be used. The disk array management terminal 370 has an OS installer 343 and sends the OS to be installed to the disk array 360 via the fiber channel interface (I / F) 371.
In FIG. 4, reference numerals 411 to 441 denote hard disks, which hold logical units (LU) 412 to 442 which are division units of the storage area. One LU may span multiple disks. The LU 412 is assigned as an external storage of the computer 301 in FIG. Similarly, the LUs 422 to 442 are used as external storage for the computers 311 to 331. An access request to the LU sent from the computers 301 to 331 and the disk array management terminal 370 is received by the fiber channel I / F 402. The access control unit 403 refers to the access control table 405 and determines whether the requested access is permitted. The access control table 405 stores computers that are permitted to be accessed for each LU. When the access request is for writing, the batch writing unit 404 refers to the batch writing group definition table 406 to determine which LU to write. The communication unit 401 receives control information from the disk array management terminal and passes it to the central control unit 407. The central control means 407 updates the access control table 405 and the batch write group definition table 406 according to the control information, and also manages the LU. The batch write group definition table 406 stores the LU and the batch write group to which the LU belongs as shown in FIG.
(2) Description of operation The operation when a new OS is installed using the batch write function for three LUs used by different computers will be described based on the flowchart of FIG.
First, if the installation destination LU does not exist, the LU is created in the disk array. When the administrator instructs the creation of an LU from the management terminal 370, the disk array control means 374 sends control information for LU creation to the disk array, and the central control means 407 of the disk array creates the LU (step 701).
If access from the computer to the LU is permitted, the access is restricted so that the computer does not read from or write to the LU being written. When the administrator instructs the LU to prohibit access from other than the disk array management terminal 370, the disk array control means 374 sends access control information to the disk array. The central control means 407 updates the access control table based on the received control information (step 702).
Next, an LU to be subjected to batch writing is designated. When the administrator selects the target LU from the management terminal, the disk array control means 374 sends control information to the disk array so as to define the selected LU as the same group for batch writing. The central control means 407 updates the batch write group definition table based on the received control information. For example, in FIG. 5, when batch writing to LU1, 2, 4 is performed, as shown in the figure, these three LUs are updated so as to belong to the same batch write group (group A in the figure). Similarly, in FIG. 5, LU3, 5, and 7 are also defined as belonging to the same group (group B in FIG. 5) as a batch write target (step 703).
Now that you're ready to do bulk writing, follow the steps above to install the OS. The administrator installs the OS using the installer 373, and designates one of LUs to be collectively written as an installation destination. Here, as an example, it is installed in LU1 in FIG. The write request from the installer is received by the fiber channel I / F 402 of the disk array via the fiber channel I / F 371, the fiber channels 345 and 346, and the fiber channel connection means 350 (step 704).
The access control means 403 refers to the access control table in order to determine whether or not the received access request to LU1 is permitted (step 705). Since the control table has been updated in step 703 to permit access from the management terminal, access is permitted and the request is passed to the batch writing means 404 (step 706).
The batch writing unit 404 that has received the request refers to the batch writing group definition table in order to determine a destination LU for writing (step 708). From the definition table of FIG. 5, as updated in step 705, it can be seen that LU1 belongs to batch write group A, and group A includes LU2, 4 in addition to LU1. Accordingly, the batch writing unit 404 writes the same contents to not only LU1 but also LU2 and 4 collectively (step 709).
After installation is complete, delete the batch write group definition so that each LU can be accessed individually. When the administrator gives an instruction from the management terminal 370, the disk array control means 374 sends information for deleting the group definition to the disk array. The central control means 407 deletes the group definition based on the received information and updates the group definition table (step 710).
Further, the access to the LU from the prohibited computer is lifted so that the LU can be used from the computer. When the administrator instructs from the management terminal 370 to permit access from the computer to the LU, the disk array control means 374 sends access control information to the disk array. The central control means 407 updates the access control table based on the received control information (step 711).
Also, the access control means 403 refers to the access control table 405 and the access is prohibited for the access request from the computer to the LU being installed or for the LU for which access from the management terminal is prohibited. Therefore, it is rejected (step 707).
(3) Effects According to this embodiment, even when the OS has to be installed in many LUs, the administrator can install all LUs at once, reducing system operating costs. can do. In addition, since each LU is an external storage of a different computer, as a result, it can be installed in a batch on the external storage of a plurality of computers.
As an example of the operational cost reduction effect, consider the case where an OS is installed in the external storage of n computers. Assuming that one OS installation time is t and labor cost per hour is p, in the conventional technology, since each user installed on each computer, the total operation cost of ntp was required. In this embodiment, since one administrator can install all LUs at once, the operation cost is tp, which is reduced to 1 / n. In the prior art, in practice, t is not constant for each user, and the installation time for users with low proficiency is longer than t. In addition, the operation cost is smaller than 1 / n in consideration of the operation error at the time of installation and the cost corresponding to the inquiry from the user about the procedure.
Second embodiment (Batch writing after writing different contents to each LU)
A second embodiment will be described. In this embodiment, after the OS is installed in a plurality of LUs as in the first embodiment, different corrections are made for each LU. For example, to give each computer a different host name, the OS file storing the host name is modified. After that, the same application software is collectively installed on these LUs. When performing batch writing, the LU before writing must have the same file system (FS) configuration. In other words, the number, size, and storage location of files and FS management data (structures for managing file storage areas) in each LU must be the same. Here, assuming that modifications after OS batch installation are performed within the range of this condition, the batch writing function is used for application installation.
Only differences from the first embodiment will be described below.
(1) Description of configuration The configuration is the same as in FIGS. The batch write group definition table 406 in FIG. 4 is as shown in FIG. 5 in the first embodiment, but in this embodiment, the correspondence between virtual LUs and real LUs is defined as shown in FIG. The The real LU is a storage area unit created inside the disk array, which is simply called LU in the first embodiment. A virtual LU is a group of one or more real LUs. As a destination of access requests from the computers 301 to 331 and the disk array management terminal 370, a virtual LU is designated instead of a real LU. The access control unit 403 also controls access to the virtual LU. The real LU is recognized only from the disk array control means 374 of the management terminal 370.
(2) OS batch installation
The operation of batch installation of OS will be described using the flowchart of FIG. When creating the LU, the central control means 407 defines not only the real LU but also the virtual LU corresponding to the real LU in the access control table 405 and the batch write group definition table 406, respectively. For example, in FIG. 6, V1 to V5 are defined as virtual LUs corresponding to the real LUs 1 to 5 on a one-to-one basis. These virtual LUs are used as destination LUs when accessing individual real LUs (step 701).
When defining a batch write group, a new virtual LU representing the group to be defined is defined in the access control table 405 and the group definition table 406. For example, in FIG. 6, a virtual LU V6 represents a group of real LUs 1, 2, and 4. The virtual LU entry corresponding to the group definition in the access control table 405 is created in a state where access from the computer is prohibited (step 703).
The administrator designates a virtual LU representing a batch write group as the installation destination when performing OS batch installation. The batch write unit 404 refers to the batch write group definition table 406 and writes to all the real LUs corresponding to the virtual LU designated as the destination of the access request (steps 708 and 709).
After the writing is completed, steps 710 and 711 are not performed, and each LU is individually corrected.
(4) In order to write to individual real LUs while retaining individual modifications and batch installation batch write group definitions for each LU, a virtual LU that has a one-to-one correspondence with each real LU as the destination of the access request Is specified. For example, in FIG. 6, in order to write only to the real LU 1 while maintaining the group definitions of the real LUs 1, 2, 4 (virtual LU V6 definition), the virtual LU V1 is designated as the destination of the access request. Similarly, writing to the real LUs 2 and 4 is performed by designating the virtual LUs V2 and V4 as destinations.
After completing the individual corrections, install the applications in a batch. As the installation destination, a defined virtual LU V6 is specified. The operation is the same as the batch installation of OS. Finally, access from the computer to the virtual LU corresponding one-to-one with the real LU is permitted. The access request is granted by updating the access control table 405 as in the first embodiment.
(5) Effect In the first embodiment, in a state where a batch write group is defined, it is not possible to individually write to each LU belonging to the group, and the group definition must be deleted in order to write individually. According to this embodiment, it is possible to individually write to each LU without deleting the group definition, and it is possible to reduce the work time required for managing the group definition.
Third Embodiment (Application in Network Attached Storage Device)
The present invention can be applied not only to the disk array connected to the fiber channel as shown in the above-described two embodiments but also to other forms of external storage devices. In this embodiment, a configuration using a network-connected storage apparatus will be described. Only differences from the first embodiment will be described.
In FIG. 8, 801 to 804 are client computers directly used by the user, 830 is a network-connected storage device (NAS) that provides external storage to the computers 801 to 804, and 820 is a storage management terminal for managing the NAS 830. These are connected to each other by a LAN 810. The NAS 830 has a communication means 831 and directly accesses the LAN. Communication of control information between the NAS 830 and the management terminal 820 and communication of access requests with the client computers 801 to 804 are all performed via the LAN 810.
When the administrator controls the NAS 830 from the management terminal 820, the storage control means 823 sends control information and is received by the communication means 831 via the communication means 821 and the LAN 810. The access control means 833 refers to the access control table 835 and checks whether the transmission source of the control information has the authority to instruct control. If there is authority, the central control means 832 performs processing based on the control information. Other parts of the configuration and operation are the same as those in the above-described two embodiments.
According to this embodiment, even in a computer environment connected by a LAN that has been widely used in the past, an operation cost reduction effect using the batch writing function can be obtained.
Fourth embodiment (application in server-attached storage system)
In this embodiment, a configuration using a server-connected storage device (SAS) will be described. Only differences from the third embodiment will be described.
In FIG. 9, reference numerals 901 to 904 denote client computers, a storage server 920 denotes a storage server that provides external storage to the computers 901 to 904, and 930 denotes a disk array that provides an actual storage area of external storage provided by the storage server 320. . The administrator performs LU management, access control, and batch write group management in the storage server. The computers 901 to 904 and the storage server 920 are connected by a LAN 910, and the storage server 920 and the disk array 930 are connected by a high-speed I / O channel. The central control unit 923 of the storage server 920 controls the group definition table update unit 932 of the disk array 930 in addition to updating the access control table 924 and managing LUs.
When the administrator defines a batch write group in the storage server 920, the central control unit 923 sends control information to the group definition table update unit 932 via the communication units 925 and 931. The group definition table update unit 932 updates the batch write group definition table 934 based on the control information and defines a group. When installing the OS or application, the administrator instructs the installation from the storage server 920, and the installer 926 sends the data to the batch writing means 933 via the communication means 925 and 931. Other parts of the configuration and operation are the same as in the third embodiment described above.
According to this embodiment, even in a computer environment using a storage server, it is possible to obtain an operation cost reduction effect using the batch write function without adding a dedicated storage management terminal.
Fifth embodiment (application in video on demand system)
The present invention can be applied not only to LU provided as external storage of a client computer but also to other usage forms. A video-on-demand (VOD) system reads moving image data stored on a disc in response to a request from a user, and distributes it to a receiving terminal via a network. Even when many distribution requests for the same moving image data are concentrated, the moving image data is duplicated on several different disks in order to ensure the reading speed from the disk. In the present embodiment, writing of moving image data in the VOD system will be described. Only differences from the first embodiment will be described.
(1) Explanation of configuration In FIG. 10, 001 to 004 are receiving terminals that are moving image data distribution destinations, 020 is a distribution control means that performs distribution scheduling and address management, 040 is a disk array that stores moving image data, 030 is a disk array management terminal. The receiving terminals 001 to 004 and the distribution control unit 020 are connected by a distribution network 010, and the distribution control unit 020 and the disk array 040 are connected by an I / O channel. The disk array management terminal 030 and the disk array 040 are connected by a communication path 051 for control information and a communication path 081 for moving image data. In the VOD system, LU stores video data, not OS or applications. About another structure, it is the same as that of 1st embodiment.
(2) Description of operation When the administrator instructs the disk array management terminal 030 to write moving image data to the disk array 040, the data is sent to the batch writing means 044 via the communication path 081 and the communication means 048. The batch writing unit 044 refers to the destinations defined in the batch writing group definition table 047 and writes the moving image data to a plurality of discs at once. About other operation | movement, it is the same as that of 1st embodiment.
(3) Effects According to the present embodiment, when the video data of the VOD system is written to the disk array, it is possible to create a duplicate of the video data at a time, thereby reducing the system operating cost. .
【The invention's effect】
As described above, according to the present invention, since one operator performs writing to a plurality of external memories, the operation cost of the system can be reduced.
Furthermore, according to the present invention, writing to the external storage of a plurality of computers can be performed collectively.
[Brief description of the drawings]
FIG. 1 is a diagram showing an external storage update according to the prior art.
FIG. 2 is a configuration diagram of a conventional RAID1.
FIG. 3 is an overall configuration diagram of the first embodiment of the present invention.
FIG. 4 is a configuration diagram of a disk array according to the first embodiment of this invention.
FIG. 5 is a configuration diagram of a batch write group definition table of the present invention.
FIG. 6 is a configuration diagram of a batch write group definition table in the second embodiment of the present invention.
FIG. 7 is a flowchart showing a processing procedure according to the first embodiment of the present invention.
FIG. 8 is a configuration diagram of a third embodiment of the present invention.
FIG. 9 is a configuration diagram of a fourth embodiment of the present invention.
FIG. 10 is a configuration diagram of a fifth embodiment of the present invention.
[Explanation of symbols]
920 ... Storage server, 930 ... Disk array, 922 ... Access control means, 923 ... Central control means, 924 ... Access control table, 926 ... Installer, 932 ... Group definition table update means, 933 ... Batch write means, 934 ... Batch write Group definition table, 941 ... disk, 942 ... logical unit.

Claims (5)

A storage device having a plurality of logical units;
A first means for defining access authority from a host device for each of the plurality of logical units;
A second means for defining several logical units included in the plurality of logical units as one group;
A third means for referring to the definition by the second means, and writing data transmitted from the host device to each logical unit included in the group;
The first means uses a first table that stores information associating a plurality of higher-level devices with a plurality of logical units that are permitted or prohibited to access from the plurality of higher-level devices. Define access authority to allow access from one higher-level device to the logical unit and prohibit access from higher-level devices other than the one higher-level device,
Further, the second means uses a second table for storing information associating the plurality of logical units whose access authority is defined by the first means and a group to which the plurality of logical units belong. , Defining several logical units to which data is to be written from among the plurality of logical units permitted to be accessed from the one higher-level device as a group,
The third means writes the data received from the one higher-level device to each logical unit included in the group,
The second means releases the definition of the group and updates the second table;
The first means updates the first table by changing an access authority so as to permit an access from a host device other than the one host device to the plurality of logical units. A storage device system. A storage device having a plurality of logical units;
A central control means;
Writing means for writing data received from the host device to each of the plurality of logical units;
The central control means creates a plurality of first virtual logical units corresponding to the plurality of logical units,
The central control means defines several logical units included in the plurality of logical units as one group, creates a second virtual logical unit corresponding to the group,
The central control means grants access authority to the second virtual logical unit so as to permit access from a certain higher-level device and prohibit access from higher-level devices other than the one higher-level device. Define
The writing means writes data received from the one higher-level device to each of the several logical units corresponding to the second virtual logical unit,
The central control means changes the access authority so as to allow access from a host device other than the one host device to the plurality of first virtual logical units,
The writing unit writes data received from a host device other than the one host device to each of the plurality of logical units corresponding to the plurality of first virtual logical units. system. Further, the central control unit allows the second virtual logical unit to be accessed from the one higher-level device and forbids access from a higher-level device other than the one higher-level device. Change access permissions,
The writing means writes the data received from the one higher-level device again to the several logical units corresponding to the second virtual logical unit. Claim Three The storage device system described. An access method for a storage system having a plurality of logical units connected to a plurality of host devices,
A first relationship that defines an access right to permit access from one higher-level device to each of the plurality of logical units and to prohibit access from higher-level devices other than the one higher-level device. The first step to setup,
Based on the first relationship, a second logical unit that defines several logical units to which data is to be written as a group from among the plurality of logical units permitted to be accessed from the one higher-level device. Steps,
A third step of referring to the group and writing data received from the one higher-level device to each logical unit included in the group;
A fourth step of undefining the group;
A fifth step of changing access authority so as to permit access to the plurality of logical units from a host device other than the one host device;
A method for accessing a storage system. An access method for a storage system having a plurality of logical units connected to a plurality of host devices,
A first step of creating a plurality of first virtual logical units corresponding to each of the plurality of logical units;
A second step of defining several logical units as one group out of the plurality of logical units and creating a second virtual logical unit corresponding to the group;
A third step of defining access authority so as to permit access from a certain host device to the second virtual logical unit and prohibit access from host devices other than the one host device. When,
A fourth step of writing data received from the one higher-level device to each of the plurality of logical units corresponding to the second virtual logical unit;
A fifth step of changing access authority so as to permit access to the plurality of first virtual logical units from a host device other than the one host device;
A sixth step of writing data received from a host device other than the one host device to each of the plurality of logical units corresponding to the plurality of first virtual logic units;
A method for accessing a storage system.

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