JP2015129994A - Transmission program, transmission method, and transmission apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a communication program that restrains redundant data transmission at the time of communication failure without requiring a memory area for storing the progress of data transmission separately from the storage destination of transmitted data.SOLUTION: Processing to be executed by a transmission apparatus 1 includes processing to transmit each of multiple second information sets contained in first information to an information processing apparatus 2 that can access a memory apparatus, cause the transmitted second information to be stored in the memory unit, if the transmission of the second information is interrupted and later restored acquires progress report information from the information processing apparatus 2 in whose memory unit area that would permit writing-in until the completion of the transmission of the multiple second information sets and is to be used upon and after the completion of transmission, specify the set or sets of multiple second information sets to be transmitted after the restoration, and resume transmission of the specified set or sets of second information.

Description

  The present invention relates to data transmission.

  In the construction of an information processing system using an information processing apparatus, a disk image (system image) is distributed from a transmission apparatus to a target apparatus to be distributed. In the target device, the distributed disk image is expanded, and a system of the expanded disk image is constructed.

  In constructing such an information processing system, for example, in the form of SaaS (Software as a Service), a disk image may be distributed via the Internet. In this case, it is necessary to consider communication interruption during distribution unlike an environment where a sufficient network bandwidth is ensured when distributing a disk image. If communication interruption is not taken into account, it is impossible to know how far the data has been transmitted. Therefore, when communication interruption occurs, data that has already been transmitted must be retransmitted, and redundant data transmission is not possible. Occur.

  As an example of a method for updating software via a network, for example, there is the following communication system. That is, the communication system includes a host station and a plurality of terminals, and provides services such as home shopping and information services to terminal users. In the communication system, when the terminal operation program is upgraded, the upgraded program is downloaded from the host station to the terminal. Then, when the terminal receives a service using the operation program stored in the nonvolatile memory, the terminal includes a control means for downloading using the idle time of the telephone line while receiving the service. Have.

JP-A-7-225725

  Considering the occurrence of communication interruption during disk image distribution, a separate storage area is provided that is different from the disk image distribution destination storage area (the area where the disk image is expanded), and the progress of distribution is maintained in that area. There is technology to do.

  However, in an aspect in which a separate storage area is provided to maintain the progress of distribution, if the separate storage area is volatile, data is lost due to the power-off of the apparatus. In addition, when the separate storage area is nonvolatile, there is a problem that the cost increases because the nonvolatile storage area for maintaining the progress status is increased.

  Accordingly, in one aspect, an object of the present invention is to provide a communication program that suppresses redundant data transmission when communication is interrupted.

  The process according to one aspect of the program causes the computer to transmit each of the plurality of second information included in the first information to an information processing apparatus accessible to the storage device, and store the transmitted second information in the storage device In the case where the interruption is restored after the transmission of the second information is interrupted, an area in the storage device that is writable until the transmission of the plurality of second information is completed, and the area that is used after the transmission is completed, The progress information is acquired from the information processing apparatus storing the progress information that identifies the progress of storing the plurality of second information, and is transmitted after recovery from the plurality of second information based on the acquired progress information. Including the process of identifying the second information to be performed and restarting the transmission of the identified second information.

  According to one aspect, it is possible to provide a communication program that suppresses redundant data transmission when communication is interrupted.

An example of the header format of MBR is shown. An example of a GPT management format is shown. It is a functional block diagram illustrating the configuration of a transmission device according to an embodiment. 1 shows an example of a configuration of an information processing system according to a first embodiment. An example of the data of transmission block identification information is shown. An example of data of reception block identification information is shown. The specific example of the data of area | region identification information is shown. It is a figure for demonstrating the change of the receiving block identification information at the time of receiving data. FIG. 5 is a sequence diagram for explaining an operational relationship between a distribution server and a target server when disk image distribution is interrupted according to the first embodiment. 3 is a flowchart illustrating contents of transmission processing of a transmission processing unit of the distribution server according to the first embodiment. 3 is a flowchart illustrating the contents of a retransmission process of a transmission processing unit of a distribution server according to the first embodiment. 4 is a flowchart illustrating contents of reception processing of a reception processing unit of a target server according to the first embodiment. 4 is a flowchart illustrating the contents of a re-receiving process of a receiving processing unit of a target server according to the first embodiment. An example of the hardware constitutions of a delivery server and an object server is shown. 4 shows an exemplary configuration of an information processing system according to a second embodiment. 10 shows a flow of disk image distribution and interruption processing of the information processing system according to the second embodiment. 9 shows a processing flow from disk image distribution interruption to restart in the information processing system according to the second embodiment.

  If the progress information of the distribution of the disk image is simply stored in the storage area to which the image is deployed in preparation for the communication interruption during the distribution of the disk image from the transmission device to the target device, for example, the progress information is Overwritten by expansion. In addition, even if progress information is stored in a free area in the disk image, the free area is a storage area that can be referred to in other processes, and other processes operate during image expansion. May malfunction. For this reason, it is desirable that the storage area for holding the progress information and the mode of holding do not affect the distribution and development of the disk image (no malfunction or unintentional overwriting).

  It is also conceivable to store the progress information in a recovery area used by the interruption restoration program included in the disk image. However, there is a possibility that such a recovery area is not included in the disk image. In the case of pay-as-you-go billing according to the disk capacity like SaaS, it is due to circumstances such as billing saving.

  Further, even if the recovery area is provided in the disk image, the recovery area cannot be correctly determined without a determination material for distinguishing between the recovery area and the disk image development destination area. In order to acquire information that can be used as a basis for such determination, it is necessary to further cooperate with (at least) software that manages the recovery area. For this reason, when the progress information is stored in the recovery area, the revision load accompanying the application of such software increases. In addition, the recovery area is implemented in a format unique to each vendor, and its specifications may not be disclosed. Further, such a recovery area is an area that is used only when the disk image is expanded, and is not desirable from the viewpoint of the efficiency of use of the disk after the expansion.

  In view of the situation as described above, in the information processing system according to the embodiment, as a storage area for storing progress information in the target apparatus, an area that can be written until the completion of the transmission of the disk image and is used after the completion of the transmission Is used. Specifically, for example, in the information processing system according to the embodiment, the progress information is stored in an area in the storage device after the disk image is expanded, and the information processing apparatus is activated using the disk image. An area for storing information to be referred to is used. More specifically, for example, in the information processing system according to the embodiment, an area of a master boot record (MBR (Master Boot Record)) included in a disk image is used as an area for storing progress information. In other words, in the information processing system of the embodiment, the distribution target apparatus stores information for progress management in the MBR area of the disk image during distribution and development of the disk image. When the development of the disk image is completed, the target apparatus receives the data in the MBR area again and stores the correct data in the MBR area used for progress management. If communication disconnection occurs during the distribution of the disk image, the transmission device, when resuming the distribution, distributes data from anywhere in the disk image based on the information for progress management stored in the MBR area of the target device. Specify whether to resume. Then, the transmission device resumes the distribution of the disk image from the specified data.

  In this way, even if communication disconnection occurs during the distribution of the disk image, the distribution can be resumed from the data specified based on the progress information from the target device when the distribution is resumed. Data transmission can be suppressed. In addition, by storing information for managing the progress of distribution in the MBR area of the disk image and finally storing the correct data in the MBR area, it is possible to prevent the progress information from being overwritten by image expansion. it can. In addition, because the information for progress management is stored in the disk image, it is not necessary to secure a separate area for progress management in addition to the area where the disk image is deployed, thereby reducing the cost of distribution. It is possible to prevent deterioration of resource use efficiency.

  FIG. 1 shows an example of the MBR header format. The MBR includes areas of a bootstrap loader 11, a partition table 12, and a boot signature 13. The bootstrap loader 11 area stores a program related to booting. In the area of the partition table 12, information related to the partition is stored. In the boot signature 13 area, a value indicating that MBR is valid (specifically, for example, “0xAA55”) is stored.

  In the target device, a GPT (GUID Partition Table) in which MBR is expanded may be used to cope with an increase in the managed disk size. FIG. 2 shows an example of the GPT management format. As shown in FIG. 2, the GPT management format has an MBR in common. Therefore, even when the GPT is used in the target device, the progress information can be managed using the MBR included in the GPT.

  However, although the MBR size is a relatively small size of 512 bytes, the GPT size is larger than the MBR. This is because the GPT includes a plurality of GPT headers and a partition table in addition to the MBR region. For this reason, comparing the probability that an unexpected communication interruption occurs during the delivery of the MBR area and the probability that an unexpected communication interruption occurs during the distribution of the GPT area, the size of the distribution area is large. There is a high probability that an unexpected communication interruption will occur during distribution.

  The GPT area includes a special area that is particularly required to ensure data reliability. In the embodiment, regarding a general area other than the special area, if an unexpected communication interruption occurs during distribution, data is retransmitted in units of blocks. However, with regard to a special area where reliability is required, in the embodiment, in order to ensure data reliability, restoration is performed not in units of blocks but in units of meaningful data. That is, when a communication interruption occurs during transmission of data in the special area, transmission is performed again from the first block among the blocks included in the special area in the retransmission process. In this way, regarding a particularly important area in the disk image, data can be retransmitted from the beginning again in the retransmission process, and reliability can be improved.

  The special area is an area such as the MBR, the first GPT header, the first GPT entry array, the second GPT entry array, and the second GPT header in the example of FIG.

  In order to ensure data reliability, when communication interruption occurs during distribution, if a communication interruption occurs for a special area where blocks are retransmitted from the beginning of the area, retransmission is performed in block units. An area where the process is performed is referred to as a general area. If communication interruption occurs during transmission of data in the general area, in the retransmission process, transmission is resumed from the block next to the block whose reception has been completed.

  In the embodiment, data for progress management is written in the MBR. Since data for progress management is stored in the MBR instead of data used for the original use, the MBR is used for the original use when the data for progress management is written. Can not be used. Specifically, the area for storing data for progress management is the area of the bootstrap loader 11 and boot signature 13 of the MBR.

  Here, the validity of the MBR is guaranteed by the boot signature 13. That is, if correct data (specifically, for example, “0xAA55”) is not set in the boot signature 13, the MBR is treated as invalid. In the embodiment, since the progress management data is stored in the area of the boot signature 13, the MBR itself is treated as invalid during distribution. Therefore, the OS (Operating System) of the target device is not activated while data for progress management is being written to the MBR, that is, during distribution and deployment of the disk image. This brings about an effect of preventing erroneous activation of the target device due to an operation error or the like during distribution and development of the disk image.

  If correct data is set in the boot signature 13, the bootstrap loader 11 can access the OS loader. If a communication disconnection occurs in the middle of disk image distribution and the correct value is set in the boot signature 13, the target device can start an incomplete OS that is in the middle of disk image distribution. It becomes a state. In this case, when communication disconnection occurs in the middle of system distribution and the system is restarted, incomplete OS loading may be started, and an error may occur during OS initialization processing. In such a case, in order to continue the recovery, it is necessary to change the startup sequence of BIOS (Basic Input / Output System). This causes extra communication between the transmission device and the target device, and takes a long time to recover. Therefore, suppressing erroneous start during distribution and deployment of the disk image leads to improvement of the overall quality of the service.

  Even if incorrect data is stored in the boot signature 13, if the original program is stored in the bootstrap loader 11, the OS loader may be activated. By overwriting the data in this area with the progress information, the bootstrap loader 11 cannot access the OS loader. Therefore, it is possible to prevent an incomplete OS startup that is in the process of distributing the disk image.

  Here, the disk image is an image file in which the entire disk of the system to be built on the target device is filed. Data obtained by dividing a disk image into predetermined sizes is referred to as image data or blocks. It is assumed that the transmission device transmits data to the target device for each block.

  FIG. 3 is a functional block diagram illustrating the configuration of the transmission apparatus according to the embodiment. In FIG. 3, the transmission device 1 includes a transmission unit 3, an acquisition unit 4, and a resumption unit 5. The transmission device 1 is connected to the information processing device 2 via a network or the like.

  The transmission unit 3 transmits each of the plurality of pieces of second information included in the first information to an information processing apparatus that can access the storage device, and stores the transmitted second information in the storage device.

  When the interruption is recovered after the transmission of the second information is interrupted, the acquisition unit 4 is an area in the storage device that can be written until the transmission of the plurality of second information is completed, and is used after the transmission is completed. The progress status information is acquired from the information processing apparatus 2 that stores the progress status information for specifying the progress status of the storage of the plurality of second information in the area.

  The resuming unit 5 identifies second information to be transmitted after recovery from among the plurality of second information based on the progress information acquired by the obtaining unit 4, and resumes transmission of the identified second information.

  The first information is a disk image applied to the information processing apparatus 2, and the second information is image data included in the disk image.

  The area in the storage device that is writable until the transmission of a plurality of second information is completed and that is used after the transmission is completed is activated by the information processing apparatus 2 using the disk image after the disk image is expanded. This is an area for storing information to be referred to when being performed.

  Further, an area in the storage device that is writable until transmission of a plurality of second information is completed, and is used after the transmission is completed, is a storage area in which a master boot record included in the disk image is stored.

  In addition, an area in the storage device that is writable until the transmission of the plurality of second information is completed and is used after the transmission is completed is the boot signature 13 and the boot in the storage area in which the master boot record is stored. This is an area where the strap loader 11 is stored.

  The area where the boot signature 13 is stored is different from the information indicating that the master boot record is valid by storing the progress information in response to the second information being stored in the storage device. Information is stored.

  The transmission unit 3 transmits the information of the master boot record included in the disk image stored in the area where the progress status information is stored to the information processing apparatus 2 after the transmission of the disk image is completed.

(Embodiment 1)
Next, the configuration of the information processing system according to the first embodiment will be described. FIG. 4 shows an example of the configuration of the information processing system according to the first embodiment. The information processing system according to the first embodiment includes a distribution server 21 and a target server 22. The distribution server 21 and the target server 22 are connected via a network such as the Internet. The distribution server 21 transmits the disk image to the target server 22, and the target server 22 expands the disk image received from the distribution server 21 (writes it to the disk of the target server). The distribution server 21 is an example of the transmission device 1. The target server 22 is an example of the information processing apparatus 2.

  The distribution server 21 includes a transmission processing unit 23 and a transmission information storage unit 24. The transmission processing unit 23 is an example of the transmission unit 3, the acquisition unit 4, and the resume unit 5.

  The transmission processing unit 23 performs a transmission process of reading the disk image stored in the transmission information storage unit 24 and transmitting the read disk image to the target server 22. In addition, when the transmission process is interrupted, the transmission processing unit 23 performs a disk image re-transmission process when detecting that the distribution can be resumed.

  In the distribution of the disk image according to the first embodiment, it is assumed that the transmission order of data included in the disk image is predetermined. For example, first, the special area data of the disk image is transmitted, and then the general area data is transmitted. Further, the data in the special area and the general area are transmitted in the ascending order of the block numbers (or addresses) in the areas. The order of transmission is not particularly limited as long as the order of transmission is recorded by the distribution server 21 and the target server 22, for example.

  In the transmission processing, the transmission processing unit 23 performs pre-transmission processing for MBR initialization before transmitting the first block of the disk image. Further, when transmitting the disk image data, the transmission processing unit 23 manages the progress of the disk image transmission status.

  In the pre-transmission process, the transmission processing unit 23 fills the areas of the bootstrap loader 11 and the boot signature 13 in the MBR area of the disk image with “0”. This is because the area of the bootstrap loader 11 and the area of the boot signature 13 in the MBR area are used for progress management in the target server 22, and the progress management is performed because the value of these areas is “0”. Indicates that the information has been initialized. In the following description, the process of filling the bootstrap loader 11 and the boot signature 13 with “0” before distributing the disk image is referred to as an initialization process. Note that the GPT areas other than the bootstrap loader 11 and the boot signature 13 are not initialized. That is, the MBR partition table area, the GPT header, the GPT partition table, and the GPT trailer area are protected because the physical position of the disk in the image expansion process is calculated.

  The initialization process is not limited to the above, and a value indicating that the meaningless data is stored in the area of the bootstrap loader 11 and the value of the boot signature 13 is invalid (that is, a value other than “0xAA55”). If it becomes, it will not specifically limit. If the areas of the bootstrap loader 11 and the boot signature 13 are initialized and distributed before transmission, the target server 22 can prevent an unexpected OS startup during the reception of the disk image.

  In the progress management, the transmission processing unit 23 manages to what extent the transmission of the disk image to the target server 22 has progressed using the transmission block identification information. The transmission block identification information stores information for specifying the block next to the block for which transmission has been completed. Using the transmission block identification information 40, the transmission processing unit 23 specifies a block that starts transmission first in the retransmission processing when a distribution interruption occurs.

  FIG. 5 shows an example of transmission block identification information data. In FIG. 5, the transmission block identification information 40 includes area identification information 41 and a block number 42.

  The area identification information 41 is identification information for identifying the next area after the most recently transmitted area. Here, the “region where transmission has been completed” refers to a region where transmission of all data included in the region has been completed. The “next” area refers to an area in which data to be transmitted “next” is stored in the data transmission order in the disk image. This “region” is one of a plurality of special regions or general regions. In other words, it can be said that the area identification information 41 is identification information of an area in which a block currently being transmitted is stored.

  The block number 42 is information indicating the block number next to the block number of the block whose transmission has been completed most recently. In other words, it can be said that the block number 42 is the block number of the block currently being transmitted. The block number 42 stores the block number of the block in the general area and does not store the block number in the special area. The block number 42 is not limited to a block number as long as it can identify a block that has been transmitted most recently, and may be various information such as an address of a block in a disk image.

  In the progress management, the transmission processing unit 23 stores, in the area identification information 41 of the transmission block identification information 40, the area identification information indicating the next area after the transmission of all the blocks included in a certain area. To do. Further, every time transmission of a block in the general area is completed, the transmission processing unit 23 stores the block number next to the block number of the block for which transmission has been completed in the block number 42 of the transmission block identification information 40.

  When the disk image transmission process is interrupted, the transmission processing unit 23 sets an interruption flag indicating that the transmission process is interrupted. When the interruption flag is set, the transmission processing unit 23 waits until it is detected that the distribution can be resumed. When it is detected that the distribution can be resumed, the transmission processing unit 23 cancels the setting of the interruption flag and starts the retransmission process.

  When the distribution server distributes the disk image to a plurality of target servers, the interruption flag may include identification information for identifying each of the plurality of target servers. The transmission processing unit 23 can identify the target server for which the distribution process is suspended by checking the suspension flag.

  In the retransmission process, the transmission processing unit 23 first transmits a distribution resumption request to the distribution target server 22 for which distribution has been interrupted. Next, the transmission processing unit 23 receives information for progress management from the target server 22 and specifies a block to be transmitted first in the retransmission processing based on the received information. Then, from the identified block, the transmission processing unit 23 resumes the transmission process. Details of the process of specifying the block to be transmitted first in the retransmission process will be described later. In the re-transmission process, progress management is performed in the same manner as in the transmission process.

  When the transmission of all the data included in the distribution target disk image is completed, the transmission processing unit 23 again stores the data of the bootstrap loader 11 and the boot signature 13 in the MBR area (without performing the initialization process). Transmit to the target server 22. Note that all data in the MBR area may be retransmitted.

  The transmission information storage unit 24 stores a disk image distributed to the target server 22, transmission block identification information 40, and an interruption flag.

  Next, the target server 22 will be described. The target server 22 includes a reception processing unit 25 and a reception information storage unit 26.

  The reception information storage unit 26 is an area where the disk image data received from the distribution server 21 is expanded.

  The reception processing unit 25 receives the disk image data transmitted from the distribution server 21 and performs a reception process of developing the received data (writing it in the reception information storage unit 26 of the target server 22). The reception processing unit 25 performs a disk image re-reception process when the reception process is interrupted.

  In the reception process, the reception processing unit 25 receives the disk image data transmitted from the distribution server 21 and expands the received data. At this time, the progress of the data reception process is managed using the reception block identification information 50.

  FIG. 6 shows an example of the data of the reception block identification information 50. In FIG. 6, received block identification information 50 includes area identification information 51 and a block number 52. The area identification information 51 of the received block identification information 50 is stored in the area of the boot signature 13 of the MBR in the expanded disk image, and the block number 52 is the bootstrap loader 11 in the expanded disk image. Stored in the area. The areas of the bootstrap loader 11 and the boot signature 13 are areas that are transmitted after being initialized by the distribution server 21 before transmission.

  The area identification information 51 is identification information for identifying the area next to the area that has been most recently received and expanded. Here, the “region where reception and expansion has been completed” refers to a region where reception and expansion of all data included in the region has been completed. The “next” area refers to an area in which data received “next” is stored in the data transmission order in the disk image. In other words, it can be said that the area identification information is identification information of an area in which a block currently being received is stored. In the area identification information, either identification information indicating a general area or identification information indicating a plurality of special areas is stored.

  FIG. 7 shows a specific example of the data of the area identification information 51. In FIG. 7, for example, the area identification information “DCFF” indicates a general area. Further, for example, the area identification information “DC00” indicates the MBR area at the head of the disk. Note that the area identification information is not limited to the example of FIG. 7, and the value of the area identification information 51 can take a predetermined value as long as each special area and general area of the disc image can be identified. Further, for example, if there is an area other than the special area shown in FIG. 7 in which reliability is to be ensured (an area where data transmission is to be resumed from the beginning of the area when interruption occurs), this area corresponds to that area. Area identification information may be assigned. The area identification information may be the same value as the area number of the special area indicated by the area identification information, for example. Since the area identification information 51 is information stored in the area of the boot signature 13 of the MBR, the area identification information shown in FIG. 7 can also be considered as a reserved boot signature.

  The block number 52 is information indicating the block number next to the block number of the block that has been most recently received and expanded. In other words, it can be said that the block number 52 is the block number of the block currently being received. The block number 52 stores the block number of the block in the general area and does not store the block number in the special area. The block number 52 is not limited to the block number as long as it can identify the block that has been received and expanded most recently, and may be various information such as the address of the block in the disk image.

  In the block number 52 stored in the area of the bootstrap loader 11, the area identification information 51 stored in the area of the boot signature 13 stores identification information indicating a general area ("DCFF" in the example of FIG. 7). Sometimes it becomes effective. In other words, when area identification information indicating any of the special areas is stored in the area identification information 51, the block number 52 becomes invalid.

  For example, when “DCFF” is stored in the area identification information 51 and “N (positive integer)” is stored in the block number 52, the block number “N” of the general area is used in the retransmission process. Control is performed so that the transmission process is resumed from the indicated block. For example, when “DC00” is stored in the area identification information 51, the transmission process is controlled to resume from the first block of the MBR area at the head of the disk.

  The reception processing unit 25 stores the block number next to the block number of the received and expanded blocks in the block number 52 of the received block identification information 50 every time reception and expansion of the blocks in the general area are completed. In addition, every time reception and expansion of all blocks included in a certain area are completed, the reception processing unit 25 receives area identification information indicating an area in which data to be transmitted next to the data in that area is stored. Stored in the area identification information 51 of the block identification information 50.

  FIG. 8 is a diagram for explaining a change in the received block identification information 50 when data is received. (1) of FIG. 8 shows the reception block identification information 50 in the initialized state and the state of the disk image development area. In (1), the received block identification information 50 is initialized with “0”. (2) shows a state in which the reception and expansion of the block with the block number “N-2” in the general area are completed from the state of (1), and the receiving process for the block with the block number “N-1” is in the middle of processing. ing. In this case, “DCFF” is stored in the area identification information 51 of the reception block identification information 50, and “N−1” is stored in the block number 52. (3) shows a state in which the reception and expansion of the block with the block number “N-1” in the general area are completed from the state of (2) and the reception process of the block with the block number “N” is in the middle of processing. . In this case, “DCFF” is stored in the area identification information 51 of the reception block identification information 50, and “N” is stored in the block number 52. (4) shows a state in which the reception and expansion of the block with the block number “N” in the general area are completed from the state of (3) and the reception process of the block with the block number “N + 1” is in the middle of processing. . In this case, “DCFF” is stored in the area identification information 51 of the reception block identification information 50, and “N + 1” is stored in the block number 52. (5) shows a state in which the reception and expansion of the block with the block number “N + 1” in the general area are completed from the state of (4), and the receiving process for the block with the block number “N + 2” is in progress. ing. In this case, “DCFF” is stored in the area identification information 51 of the reception block identification information 50, and “N + 2” is stored in the block number 52. In this way, each time the block reception process is completed, the value of the block number 52 of the reception block identification information 50 is updated.

  When the disk image reception process is interrupted, the reception processing unit 25 starts the re-reception process. In the re-receiving process, first, the reception processing unit 25 receives a distribution resumption request from the distribution server 21. Then, the reception processing unit 25 transmits information stored in the reception block identification information 50 to the distribution server 21. Then, the reception processing unit 25 receives the resumed data from the distribution server 21 and develops it. It should be noted that the reception and expansion of data after resumption after the interruption of distribution is expanded in a form that is consistent with the data of the disk image that was expanded before the interruption. The reception processing unit 25 confirms the progress of distribution before the interruption from the reception block identification information 50, thereby developing a consistent disk image before and after the interruption. Note that management information for maintaining consistency before and after the interruption may be included in the block number 52 (that is, the area of the bootstrap loader 11) of the reception block identification information 50.

  When the reception and expansion of all the disk image data are completed, the reception processing unit 25 receives the MBR bootstrap loader 11 and the boot signature 13 data from the distribution server 21 again. Then, the reception processing unit 25 again writes the re-received data in the MBR bootstrap loader 11 and boot signature 13 areas. As a result, the original value is stored in the bootstrap area of the MBR, and the value (“0xAA55”) indicating that the MBR is valid is stored in the area of the boot signature 13. Then, the disk image reception process or re-reception process ends.

  Next, operations of the distribution server 21 and the target server 22 when the disk image distribution is interrupted will be described. FIG. 9 is a diagram for explaining the operational relationship between the distribution server 21 and the target server 22 when the disk image distribution is interrupted according to the first embodiment.

  In FIG. 9, first, the distribution server 21 detects that the distribution process can be resumed from the interruption (S91). Then, the distribution server 21 transmits a process resumption request to the target server 22 (S92).

  When receiving the process resumption request, the target server 22 refers to the received block identification information 50 (S93) and notifies the distribution server 21 of the information (S94). However, when the area identification information 51 of the reception block identification information 50 indicates a general area, the target server 22 notifies the distribution server 21 of the block number 52 of the reception block identification information 50. When the area identification information 51 of the reception block identification information 50 indicates any of the special areas, the target server 22 notifies the distribution server 21 of the area identification information 51 of the reception block identification information 50. In the following description, a part of the received block identification information 50 notified here will be referred to as a received block notification.

  When receiving the reception block notification, the distribution server 21 specifies a block to be transmitted first (hereinafter referred to as a resume block) in the retransmission process. Specifically, the distribution server 21 compares the transmission block identification information 40 with the content of the received reception block notification (S95) and determines whether or not the content matches. When the content of the reception block notification is the block number 52, the transmission processing unit 23 compares it with the block number 42 of the transmission block identification information 40. When the content of the block notification is the area identification information 51, the transmission processing unit 23 compares it with the area identification information 41 of the transmission block identification information 40.

  If it is determined that the content of the received block notification matches the content of the transmission block identification information 40, the transmission processing unit 23 identifies the block indicated by the matched content as a resume block (S96). When it is determined that the content of the reception block notification and the content of the transmission block identification information 40 do not match, the transmission processing unit 23 identifies the block indicated by the reception block notification as a resume block (S96). Alternatively, if it is determined that the content of the received block notification and the content of the transmission block identification information 40 do not match, the transmission processing unit 23 displays that the distribution cannot be resumed via a display device or the like and ends the processing. May be.

  When the restart block is specified, the transmission processing unit 23 reads the specified block, transmits it to the target server 22 (S97), and restarts the transmission process from the specified block.

  And the reception process part 25 of the object server 22 performs the reception process of the information transmitted from the delivery server 21 in a retransmission process.

  Next, a flow of transmission processing of the transmission processing unit 23 of the distribution server 21 will be described. FIG. 10 is a flowchart illustrating the contents of the transmission processing of the transmission processing unit 23 of the distribution server 21 according to the first embodiment.

  In FIG. 10, the transmission processing unit 23 first reads a block of a disk image to be distributed from the transmission information storage unit 24 (S101). Next, the transmission processing unit 23 determines whether or not the block read in S101 is the data of the MBR bootstrap loader 11 or the boot signature 13 in the disk image (S102). When it is determined that the read block is the data of the MBR bootstrap loader 11 or boot signature 13 area in the disk image (Yes in S102), the transmission processing unit 23 initializes the data of the read block (S103). ). Specifically, for example, the transmission processing unit 23 replaces all read block data with “0”. Then, the process transitions to S104.

  On the other hand, when it is determined in S102 that the read block data is neither the bootstrap loader 11 or the boot signature 13 area data in the disk image (No in S102), the transmission processing unit 23 performs the following process. Run. That is, the transmission processing unit 23 determines whether all the blocks in the area including the block read in S101 have been read (S104). When it is determined that all blocks in the area including the block read in S101 have been read, the transmission processing unit 23 sets the area identification information 41 of the transmission block identification information 40 to the area determined to have been read. The area identification information indicating the next area is updated (S105). When there is no area next to the area determined to have been read, the area identification information 41 may be updated to a value indicating that reading of all areas has been completed. Then, the process proceeds to S106.

  On the other hand, when it is determined in S104 that any block in the area including the block read in S101 has not been read (No in S104), the transmission processing unit 23 generally uses the area including the block read in S101. It is determined whether it is an area (S106). If it is determined that the area including the block read in S101 is a general area (Yes in S106), the transmission processing unit 23 sets the block number 42 of the transmission block identification information 40 to the block next to the block read in S101. Update to the block number. Then, the process proceeds to S108.

  On the other hand, if it is determined in S106 that the area including the block read in S101 is not a general area, that is, a special area (No in S106), the transmission processing unit 23 determines that the block read in S101 is the target server 22. (S108).

  Next, the transmission processing unit 23 determines whether or not transmission of all blocks included in the disk image has been completed (S109). If it is determined that transmission of any block included in the disk image has not been completed (No in S109), the process proceeds to S101, and the transmission processing unit 23 has not yet read the next in the transmission order. Read the block.

  If it is determined that the transmission of all the blocks included in the disk image has been completed (Yes in S109), the transmission processing unit 23 again selects the blocks in the bootstrap loader 11 and the boot signature 13 in the MBR area in the disk image. Read. Then, the transmission processing unit 23 transmits the read blocks of the bootstrap loader 11 and the boot signature 13 to the target server 22 (S110). Then, the process ends.

  Next, the flow of retransmission processing of the transmission processing unit 23 of the distribution server 21 will be described. FIG. 11 is a flowchart illustrating the contents of the retransmission process of the transmission processing unit 23 of the distribution server 21 according to the first embodiment. It is assumed that the flow of FIG. 11 is started from a state in which the transmission process of the disk image to the target server 22 is interrupted.

  In FIG. 11, the transmission processing unit 23 first detects that the disk image can be distributed from the interruption (S201). The detection from the interruption may be detected by, for example, the transmission processing unit 23 receiving a notification that the distribution is possible from another device, or the transmission processing unit 23 confirms the status of the network or the like. Then, it may be detected that distribution is possible. Then, the transmission processing unit 23 cancels the setting of the interruption flag.

  Next, the transmission processing unit 23 transmits a process restart request to the target server 22 (S202). The process resumption request may include predetermined software that operates on the memory of the distribution server 21 and performs control for process resumption.

  Next, the transmission processing unit 23 receives a reception block notification from the target server 22 (S203).

  Next, the transmission processing unit 23 determines whether the information included in the received block notification received from the target server 22 is the area identification information 51 (S204). When it is determined that the information included in the reception block notification is region identification information (Yes in S204), the transmission processing unit 23 matches the region identification information 41 of the transmission block identification information 40 with the region identification information 51 of the reception block notification. It is determined whether or not to perform (S205). When it is determined that the transmission block identification information 40 and the area identification information of the reception block notification match (Yes in S205), the transmission processing unit 23 identifies the first block in the area indicated by the matched area identification information as a resume block. (S206). Then, with the block identified in S206 as the block to be read, the process transitions to S101 in FIG.

  On the other hand, when it is determined in S205 that the transmission block identification information 40 and the area identification information of the reception block notification do not match (No in S205), the transmission processing unit 23 performs the following process. That is, the transmission processing unit 23 specifies the first block in the area indicated by the area identification information 51 of the received block notification as a resume block (S207). Here, the transmission processing unit 23 may perform a warning display or the like indicating that the processing is restarted with the content of the reception block notification. Then, with the block identified in S207 as the block to be read, the process transitions to S101 in FIG.

  If it is determined in S204 that the information included in the reception block notification is not area identification information (No in S204), the transmission processing unit 23 indicates that the area identification information 41 of the transmission block identification information 40 indicates a general area. It is determined whether or not (S208). When it is determined that the area identification information 41 of the transmission block identification information 40 indicates a general area (Yes in S208), the transmission processing unit 23 determines the block number 42 of the transmission block identification information 40 and the block number of the reception block notification. It is determined whether or not 52 matches (S209). When it is determined that the transmission block identification information 40 and the block number of the reception block notification match (Yes in S209), the transmission processing unit 23 identifies the block with the matching block number as a resume block (S210). Then, the process transitions to S101 in FIG. 10 with the block identified in S210 as the block to be read.

  On the other hand, when it is determined in S209 that the transmission block identification information 40 and the block number of the reception block notification do not match (No in S209), the transmission processing unit 23 identifies the block with the block number 52 of the reception block notification as a resume block. (S211). Here, the transmission processing unit 23 may perform a warning display or the like indicating that the processing is restarted with the content of the reception block notification. Then, the process transitions to S101 in FIG. 10 with the block identified in S211 as the block to be read.

  In S208, when it is determined that the area identification information 41 of the transmission block identification information 40 does not indicate a general area (No in S208), the transmission processing unit 23 performs error processing and ends the process. In the error processing, for example, the transmission processing unit 23 may perform a warning display indicating that an error has occurred via a display device or the like.

  Next, the flow of reception processing of the reception processing unit 25 of the target server 22 will be described. FIG. 12 is a flowchart illustrating the contents of the reception process of the reception processing unit 25 of the target server 22 according to the first embodiment.

  In FIG. 12, the reception processing unit 25 first receives and expands a disk image block from the distribution server 21 (S301). The reception processing unit 25 may perform control such as transmitting information (for example, ACK) indicating that data has been normally received to the distribution server 21 each time a block is received.

  Next, the reception processing unit 25 determines whether or not the block received and expanded in S301 is a general area block (S302). If it is determined that the received and expanded block is a block in the general area (Yes in S302), the reception processing unit 25 updates the block number 52 of the reception block identification information 50 (S307). Specifically, the reception processing unit 25 stores the block number of the block next to the block received and expanded in S301 in the block number 52. Then, the process transitions to S303.

  If it is determined in S302 that the received and expanded block is not a general area block (No in S302), the reception processing unit 25 receives and expands all blocks in the area including the block received and expanded in S301. It is determined whether or not it has been completed (S303).

  If it is determined in S303 that reception and expansion of any block in the area including the block received and expanded in S301 is not completed (No in S303), the process transitions to S301, and the reception processing unit 25 The next block is received and expanded.

  When it is determined in S303 that reception and expansion of all blocks in the area including the block received and expanded in S301 are completed (Yes in S303), the reception processing unit 25 determines the area identification information of the reception block identification information 50. 51 is updated (S304). Specifically, the area identification information indicating the area next to the area determined to have received and expanded all blocks is stored in the area identification information 51.

  Next, the reception processing unit 25 determines whether or not reception and expansion of all the blocks of the disk image have been completed (S305). If it is determined that reception and expansion of any block of the disk image has not been completed (No in S305), the process proceeds to S301, and the reception processing unit 25 receives and expands the next block.

  If it is determined in S305 that reception and expansion of all blocks of the disk image have been completed (Yes in S305), the reception processing unit 25 re-receives blocks in the MBR bootstrap loader 11 and boot signature 13 areas. Expand (S306). Then, the process ends.

  Next, the flow of re-reception processing of the reception processing unit 25 of the target server 22 will be described. FIG. 13 is a flowchart illustrating the contents of the re-receiving process of the receiving processing unit 25 of the target server 22 according to the first embodiment.

  In FIG. 13, first, the reception processing unit 25 receives a process resumption request from the distribution server 21 (S401). Then, the reception processing unit 25 refers to the area identification information 51 of the reception block identification information 50 and determines whether or not the area identification information 51 indicates a general area (S402). When it is determined that the area identification information 51 indicates a general area (Yes in S402), the reception processing unit 25 transmits a block number 52 to the distribution server 21 as a reception block notification (S403). Then, the process transitions to S301 in FIG.

  On the other hand, if it is determined in S402 that the area identification information 51 does not indicate a general area (No in S402), the reception processing unit 25 transmits the area identification information 51 to the distribution server 21 as a reception block notification ( S404). Then, the process transitions to S301 in FIG.

  The transmission processing unit 23 operates on the memory of the target server 22 with respect to the target server 22 before the start of the disk image distribution processing and before the start of the re-distribution processing after the distribution interruption. It may be configured to transmit software that provides 25 functions. Since this software operates on the memory of the reception processing unit 25, the contents of the software on the memory are lost when the target server is powered off. Therefore, it is not necessary to separately provide a non-volatile storage area for such software in the target server 22.

  Next, the hardware configuration of the distribution server 21 and the target server 22 will be described. FIG. 14 shows an example of the hardware configuration of the distribution server 21 and the target server 22.

  In FIG. 14, the distribution server 21 and the target server 22 include a CPU (Central Processing Unit) 501, a memory 502, a storage device 503, a reading device 504, and a communication interface 505. The CPU 501, the memory 502, the storage device 503, the reading device 504, and the communication interface 505 are connected via a bus.

  The CPU 501 of the distribution server 21 provides a part or all of the functions of the transmission processing unit 23 by executing a program describing the procedure of the flowchart described above using the memory 502. The CPU 501 of the target server 22 provides a part or all of the functions of the reception processing unit 25 by executing a program describing the procedure of the flowchart described above using the memory 502.

  The memory 502 is, for example, a semiconductor memory, and includes a RAM (Random Access Memory) area and a ROM (Read Only Memory) area. The storage device 503 is, for example, a hard disk. Note that the storage device 503 may be a semiconductor memory such as a flash memory. Further, the storage device 503 may be an external recording device. The storage device 503 of the distribution server 21 provides a part or all of the functions of the transmission information storage unit 24. The storage device 503 of the target server 22 provides a part or all of the functions of the reception information storage unit 26.

  The reading device 504 accesses the removable storage medium 550 in accordance with an instruction from the CPU 501. The detachable storage medium 550 includes, for example, a semiconductor device (USB memory or the like), a medium to / from which information is input / output by a magnetic action (magnetic disk or the like), a medium to / from which information is input / output by an optical action (CD-ROM, For example, a DVD). Note that the reading device 504 may not be included in the distribution server 21 and the target server 22.

  The communication interface 505 transmits and receives data between the distribution server 21 and the target server 22.

The program of the embodiment is provided to the distribution server 21 and the target server 22 in the following form, for example.
(1) Installed in advance in the storage device 503.
(2) Provided by the removable storage medium 550.
(3) Provided via a communication interface 505 from a program server (not shown).

  Furthermore, a part of the distribution server 21 and the target server 22 of the embodiment may be realized by hardware. Alternatively, the distribution server 21 and the target server 22 of the embodiment may be realized by a combination of software and hardware.

  The function of the transmission processing unit 23 of the distribution server 21 may be provided in a form such as SaaS.

(Embodiment 2)
In the second embodiment, the distribution server and the target server are connected via a relay device.

  FIG. 15 shows an example of the configuration of the information processing system according to the second embodiment. In FIG. 15, the information processing system includes a distribution server 601, a target server 602, a firewall 607, and a relay device 608.

  Distribution server 601 and target server 602 are connected via relay device 608. The distribution server 601 and the relay device 608 are connected via a firewall 607, and communication is controlled by the firewall 607. The relay device 608 is included in the same subnet as the target server 602. The distribution server 601 and the relay device 608 may be tunneled by SSL (Secure Sockets Layer) -VPN (Virtual Private Network). It is assumed that the target server 602 is stopped before the distribution of the disk image, and information such as the OS is not stored in the target server 602.

The relay device 608 includes a control unit 609 and a software storage unit 610.
The control unit 609 transfers the disk image distributed from the distribution server 601 to the target server 602. In the transfer, the control unit 609 does not transfer the entire disk image once but transfers it in units of packets. When distributing the disk image from the distribution server 601, the control unit 609 activates the target server 602 that has been stopped using, for example, WOL (Wake-on-LAN) technology before distribution. WOL is a technique for remotely operating a power source of a computer connected to a computer network. Then, the control unit 609 sets a network address of the target server 602 in response to a DHCP (Dynamic Host Configuration Protocol) request from the activated target server 602, for example. The control unit 609 obtains software that is executed on the memory of the target server 602 and provides the function of the reception processing unit 605 from the software storage unit 610 and transmits the software to the target server 602. In the following description, software that is executed on the memory of the target server 602 and provides the function of the reception processing unit 605 is referred to as expanded software. Then, the control unit 609 notifies the distribution server 601 of the address of the target server 602. The distribution server 601 transmits a disk image to the address notified here.

  When the disk image distribution process is interrupted, the control unit 609 transmits a distribution process interruption request to the distribution server 601. At the same time, the control unit 609 transmits a shutdown request to the target server 602. This shutdown request is made using, for example, WOL technology. When receiving information indicating that the shutdown request has been received from the target server 602, the control unit 609 transmits an end notification of the session used for distribution to the distribution server 601.

  Thereafter, the control unit 609 detects that the distribution process can be resumed. Then, the control unit 609 transmits an activation instruction to the target server 602 that transmitted the shutdown request at the time of interruption. This activation instruction is performed using, for example, WOL technology. When the control unit 609 receives a request for expanded software from the target server 602, the control unit 609 transmits the requested expanded software to the target server 602.

  Then, the control unit 609 transmits a process resumption request to the distribution server 601 and the target server 602, and receives information on the reception block identification information 50 from the target server 602 as a response. Then, the control unit 609 transfers the received reception block identification information 50 to the distribution server 601.

The software storage unit 610 stores expanded software.
The distribution server 601 includes a transmission processing unit 603 and a transmission information storage unit 604. The transmission processing of the transmission processing unit 603 is the same as that of the first embodiment, and is the same as the operation flow of FIG. However, the operation of the transmission processing unit 603 when the distribution process is interrupted is partially different from that of the first embodiment.

  When the distribution process is interrupted, the transmission processing unit 603 receives an interrupt request from the relay device 608. Upon receiving the interruption request, the transmission processing unit 603 sets an interruption flag and transmits information indicating that the interruption request has been received to the relay apparatus 608. Thereafter, upon receiving a session end notification from the relay apparatus 608, the transmission processing unit 603 ends the session with the target server 602 used in the distribution of the disk image, and sends a distribution process restart request from the relay apparatus 608. Wait for reception.

  When the processing resumption request is received from the relay device 608, the transmission processing unit 603 cancels the setting of the interruption flag. Thereafter, the reception block identification information 50 is received from the target server 602 via the relay device 608. The retransmission process after receiving the reception block notification is the same as in the first embodiment. That is, it becomes the same as the operation flow from S203 of FIG.

The transmission information storage unit 604 is the same as the transmission information storage unit 24 of the first embodiment.
The target server 602 includes a reception processing unit 605 and a reception information storage unit 606. The reception processing of the reception processing unit 605 is the same as that in the first embodiment, and is the same as the operation flow in FIG.

  However, in the second embodiment, when the distribution process is interrupted, the target server 602 receives a shutdown request from the relay device 608. When receiving the shutdown request, the target server 602 transmits information indicating that the shutdown request has been received to the relay apparatus 608, and shuts down the system. The shutdown request is made using, for example, WOL technology.

  Thereafter, when the relay device 608 detects that the distribution can be resumed, the target server 602 receives an activation instruction from the relay device 608. When the activation instruction is received, the target server 602 starts activation of the system. However, in this case, since the disk image is being distributed, the received block identification information 50 is stored in the bootstrap loader 11 and boot signature 13 areas of the target server 602. Therefore, the OS is not started. The activation instruction is performed using, for example, WOL technology.

  When the system is activated, the target server 602 transmits an acquisition request for the expanded software to the relay apparatus 608 and acquires the expanded software from the relay apparatus 608. Then, the target server 602 executes the acquired deployment software on the memory.

Thereafter, the reception processing unit 605 performs re-reception processing according to the flow of FIG. 13 described in the first embodiment. However, in the flow of FIG. 13, the transmission source of the process resumption request received in S <b> 401 is the relay device 608.
The reception information storage unit 606 is the same as the reception information storage unit 26 of the first embodiment.

  FIG. 16 is a diagram illustrating a flow of disk image distribution and interruption processing of the information processing system according to the second embodiment.

  In FIG. 16, first, the target server 602 makes a disk image distribution request to the distribution server 601 via the relay device 608 (S701).

  Upon receiving the disk image distribution request, the transmission processing unit 603 of the distribution server 601 transmits the first block (block of block number 1) included in the disk image to the target server 602 via the relay device 608 ( S702). Here, the details of the transmission processing of the transmission processing unit 603 of the distribution server 601 are the same as the flow of FIG. Then, the reception processing unit 605 of the target server 602 receives a block included in the disk image. Here, the reception processing of the reception processing unit 605 of the target server 602 is the same as the flow of FIG. However, in FIG. 16, in S301 of FIG. 12, the reception processing unit 605 of the target server 602 transmits ACK, which is information indicating that the block has been successfully received, to the distribution server 601 via the relay device 608. (S703).

  Similarly, the transmission processing unit 603 of the distribution server 601 transmits the block (block with the block number N) included in the disk image to the target server 602 via the relay device 608 (S704). When receiving the block included in the disk image, the reception processing unit 605 of the target server 602 transmits ACK, which is information indicating that the block has been successfully received, to the distribution server 601 via the relay device 608 (S705). ).

  Thereafter, when the distribution process is interrupted, the relay device 608 transmits an interruption request to the distribution server 601 (S706). Upon receiving the interruption request, the transmission processing unit 603 of the distribution server 601 sets an interruption flag and transmits information indicating that the interruption request has been received to the relay apparatus 608 (S707).

  Next, when receiving information indicating that the interruption request has been received from the distribution server 601, the relay device 608 transmits a shutdown request to the target server 602 (S708). When receiving the shutdown request, the reception processing unit 605 of the target server 602 transmits information indicating that the shutdown request has been received to the relay apparatus 608 (S709). Then, the reception processing unit 605 of the target server 602 performs shutdown processing and stops.

  When receiving the information indicating that the shutdown request has been received from the target server 602, the relay device 608 transmits a session end notification to the distribution server 601 (S710).

  Upon receiving the session end notification, the transmission processing unit 603 of the distribution server 601 disconnects and ends the session used for disk image distribution.

  FIG. 17 is a diagram illustrating a processing flow from the interruption of the distribution of the disk image to the restart of the information processing system according to the second embodiment. Note that at the start of FIG. 17, it is assumed that the distribution of the disk image to the target server 602 is interrupted and the state when the flow of FIG. 16 ends.

  In FIG. 17, the relay device 608 detects that the disk image can be distributed (S801). Then, the relay device 608 transmits an activation instruction to the target server 602 (S802).

  When the target server 602 receives the activation instruction, the system is activated (S803). At this time, since the target server 602 is in the process of developing a disk image, information for managing the progress is stored in the bootstrap loader 11 and boot signature 13 areas of the MBR of the target server 602. Therefore, the OS of the target server 602 is not activated, and the BIOS process is executed.

  Next, the target server 602 transmits a request for deployment software to the relay apparatus 608 (S804). When the relay device 608 receives the request for the expanded software, the relay device 608 reads the requested expanded software from the software storage unit 610 and transmits it to the target server 602 (S805).

  When the target server 602 receives the development software requested in S804, the target server 602 executes the development software received on the memory (S806). This deployment software is software that provides the function of the reception processing unit 605.

  Next, the relay device 608 transmits a process resumption request to the distribution server 601 (S807). When the transmission processing unit 603 receives the processing resumption request, the transmission processing unit 603 cancels the setting of the interruption flag.

  Next, the relay device 608 transmits a process resumption request to the target server 602 (S808). When receiving the processing resumption request, the target server 602 refers to the received block identification information 50 (S809), and notifies the distribution server 601 of the information via the relay device 608 (S810). Specifically, first, when receiving a process resumption request, the reception processing unit 605 refers to the area identification information 51 of the reception block identification information 50 and determines whether or not the area identification information 51 indicates a general area. When it is determined that the area identification information 51 indicates a general area, the reception processing unit 605 transmits the block number 52 of the reception block identification information 50 as a reception block notification to the distribution server 601 via the relay device 608. To do. When it is determined that the area identification information 51 indicates a special area, the reception processing unit 605 transmits the area identification information 51 of the reception block identification information 50 as a reception block notification to the distribution server 601 via the relay device 608. .

When receiving the reception block notification, the distribution server 601 performs a retransmission process.
In the retransmission process, first, the distribution server 601 compares the transmission block identification information 40 with the content of the received reception block notification, and determines whether the content matches (S811).

  That is, when the content of the reception block notification is the block number 52, the transmission processing unit 603 compares the block number 42 of the transmission block identification information 40 with the block number 52 of the reception block notification. When the content of the block notification is the region identification information 51, the transmission processing unit 603 compares the region identification information 41 of the transmission block identification information 40 with the region identification information 51 of the reception block notification.

  If it is determined that the content of the received block notification matches the content of the transmission block identification information 40, the transmission processing unit 603 identifies the block indicated by the matched content as a resume block (S812). When it is determined that the content of the reception block notification and the content of the transmission block identification information 40 do not match, the transmission processing unit 603 identifies the block indicated by the reception block notification as a resume block (S812).

  When the restart block is specified, the transmission processing unit 603 reads the specified block, transmits it to the target server 602 (S813), and restarts the transmission process from the specified block.

  Then, the reception processing unit 605 of the target server 602 performs reception processing of information transmitted from the distribution server 601 in the retransmission processing.

  Note that the processing similar to S802 to S806 in FIG. 17 may be performed before the start of the distribution processing, that is, before S701 in FIG.

  The hardware configurations of the distribution server 601, the target server 602, and the relay device 608 are the same as those shown in FIG.

  The CPU 501 of the distribution server 601 provides a part or all of the functions of the transmission processing unit 603 by executing a program describing the procedure of the above-described flowchart using the memory 502. The CPU 501 of the target server 602 provides a part or all of the functions of the reception processing unit 605 by executing a program describing the procedure of the above-described flowchart using the memory 502. The CPU 501 of the relay apparatus 608 provides a part or all of the functions of the control unit 609 by executing a program describing the procedure of the above-described flowchart using the memory 502.

  The storage device 503 of the distribution server 601 provides a part or all of the functions of the transmission information storage unit 604. The storage device 503 of the target server 602 provides a part or all of the functions of the reception information storage unit 606. The storage device 503 of the relay device 608 provides a part or all of the functions of the software storage unit 610.

  The reading device 504 may not be included in the distribution server 601, the target server 602, and the relay device 608.

  The communication interface 505 transmits and receives data between the distribution server 601 and the relay device 608 and between the relay device 608 and the target server 602.

The program of the embodiment is provided to the distribution server 601, the target server 602, and the relay device 608 in the following form, for example.
(1) Installed in advance in the storage device 503.
(2) Provided by the removable storage medium 550.
(3) Provided via a communication interface 505 from a program server (not shown).

  Furthermore, a part of the distribution server 601 and the target server 602 of the embodiment may be realized by hardware. Alternatively, the distribution server 601 and the target server 602 of the embodiment may be realized by a combination of software and hardware.

  The embodiments are not limited to the above-described embodiments, and various configurations or embodiments can be taken without departing from the gist of the embodiments.

Regarding the above embodiment, the following additional notes are disclosed.
(Appendix 1)
On the computer,
Transmitting each of the plurality of second information included in the first information to an information processing apparatus accessible to the storage device, and storing the transmitted second information in the storage device;
When the interruption is restored after the transmission of the second information is interrupted, it is an area in the storage device that is writable until the transmission of the plurality of second information is completed, and is used after the transmission is completed Acquiring the progress status information from the information processing apparatus storing the progress status information for specifying the progress status of the storage of the plurality of second information in the area;
Based on the acquired progress information, the second information to be transmitted after recovery is identified from among the plurality of second information, and the process of restarting the transmission of the identified second information is executed. program.
(Appendix 2)
The first information is a disk image applied to the information processing apparatus;
The second information is image data included in the disk image,
The area is an area in the storage device after the disk image is expanded, and is an area in which information that is referred to when the information processing apparatus is started up using the disk image is stored. The transmission program according to appendix 1, which is characterized in that it exists.
(Appendix 3)
The transmission program according to appendix 2, wherein the area is a storage area in which a master boot record included in the disk image is stored.
(Appendix 4)
The transmission program according to appendix 3, wherein the area is an area in which a boot signature and a bootstrap loader are stored in a storage area in which the master boot record is stored.
(Appendix 5)
In the area where the boot signature is stored, the progress information is stored in response to the second information being stored in the storage device, thereby indicating that the master boot record is valid. The transmission program according to attachment 4, wherein information different from the information is stored.
(Appendix 6)
In the computer,
After the completion of the transmission of the disk image, a process of transmitting the information of the master boot record included in the disk image stored in the area where the progress status information is stored to the information processing apparatus is executed. The transmission program according to any one of supplementary notes 3 to 5.
(Appendix 7)
Transmitting each of the plurality of second information included in the first information to an information processing apparatus accessible to the storage device, and storing the transmitted second information in the storage device;
When the interruption is restored after the transmission of the second information is interrupted, it is an area in the storage device that is writable until the transmission of the plurality of second information is completed, and is used after the transmission is completed Acquiring the progress status information from the information processing apparatus storing the progress status information for specifying the progress status of the storage of the plurality of second information in the area;
Based on the acquired progress status information, second information to be transmitted after recovery is identified from among the plurality of second information, and transmission of the identified second information is resumed.
(Appendix 8)
The first information is a disk image applied to the information processing apparatus;
The second information is image data included in the disk image,
The area is an area in the storage device after the disk image is expanded, and is an area in which information that is referred to when the information processing apparatus is started up using the disk image is stored. The transmission method according to appendix 7, which is characterized in that it exists.
(Appendix 9)
The transmission method according to appendix 8, wherein the area is a storage area in which a master boot record included in the disk image is stored.
(Appendix 10)
The transmission method according to appendix 9, wherein the area is an area in which a boot signature and a bootstrap loader are stored in a storage area in which the master boot record is stored.
(Appendix 11)
A plurality of second information included in the first information is transmitted to an information processing apparatus accessible to the storage device, and the transmission unit stores the transmitted second information in the storage device;
When the interruption is restored after the transmission of the second information is interrupted, it is an area in the storage device that is writable until the transmission of the plurality of second information is completed, and is used after the transmission is completed An acquisition unit for acquiring the progress status information from the information processing apparatus storing the progress status information for specifying the progress status of the storage of the plurality of second information in the area;
Based on the obtained progress status information, the second information to be transmitted after recovery is identified from among the plurality of second information, and the resuming unit that resumes the transmission of the identified second information;
A transmission device comprising:
(Appendix 12)
The first information is a disk image applied to the information processing apparatus;
The second information is image data included in the disk image,
The area is an area in the storage device after the disk image is expanded, and is an area in which information that is referred to when the information processing apparatus is started up using the disk image is stored. The transmitting apparatus according to appendix 11, wherein the transmitting apparatus is provided.
(Appendix 13)
The transmission device according to appendix 12, wherein the area is a storage area in which a master boot record included in the disk image is stored.
(Appendix 14)
The transmission device according to appendix 13, wherein the region is a region in which a boot signature and a bootstrap loader are stored in a storage region in which the master boot record is stored.

DESCRIPTION OF SYMBOLS 1 Transmission apparatus 2 Information processing apparatus 3 Transmission part 4 Acquisition part 5 Resume part 11 Bootstrap loader 12 Partition table 13 Boot signature 21 Distribution server 22 Target server 23 Transmission processing part 24 Transmission information storage part 25 Reception processing part 26 Reception information storage part 40 Transmission block identification information 41 Area identification information 42 Block number 50 Reception block identification information 51 Area identification information 52 Block number 501 CPU
502 Memory 503 Storage Device 504 Reading Device 505 Communication Interface 506 Input Device 550 Removable Storage Medium 601 Distribution Server 602 Target Server 603 Transmission Processing Unit 604 Transmission Information Storage Unit 605 Reception Processing Unit 606 Reception Information Storage Unit 607 Firewall 608 Relay Device 609 Control Part 610 Software storage part

Claims (8)

On the computer,
Transmitting each of the plurality of second information included in the first information to an information processing apparatus accessible to the storage device, and storing the transmitted second information in the storage device;
When the interruption is restored after the transmission of the second information is interrupted, it is an area in the storage device that is writable until the transmission of the plurality of second information is completed, and is used after the transmission is completed Acquiring the progress status information from the information processing apparatus storing the progress status information for specifying the progress status of the storage of the plurality of second information in the area;
Based on the acquired progress information, the second information to be transmitted after recovery is identified from among the plurality of second information, and the process of restarting the transmission of the identified second information is executed. program. The first information is a disk image applied to the information processing apparatus;
The second information is image data included in the disk image,
The area is an area in the storage device after the disk image is expanded, and is an area in which information that is referred to when the information processing apparatus is started up using the disk image is stored. The transmission program according to claim 1, wherein: The transmission program according to claim 2, wherein the area is a storage area in which a master boot record included in the disk image is stored. The transmission program according to claim 3, wherein the area is an area in which a boot signature and a bootstrap loader are stored in a storage area in which the master boot record is stored. In the area where the boot signature is stored, the progress information is stored in response to the second information being stored in the storage device, thereby indicating that the master boot record is valid. The transmission program according to claim 4, wherein information different from information is stored. In the computer,
After the completion of the transmission of the disk image, a process of transmitting the information of the master boot record included in the disk image stored in the area where the progress status information is stored to the information processing apparatus is executed. The transmission program according to any one of claims 3 to 5. Transmitting each of the plurality of second information included in the first information to an information processing apparatus accessible to the storage device, and storing the transmitted second information in the storage device;
When the interruption is restored after the transmission of the second information is interrupted, it is an area in the storage device that is writable until the transmission of the plurality of second information is completed, and is used after the transmission is completed Acquiring the progress status information from the information processing apparatus storing the progress status information for specifying the progress status of the storage of the plurality of second information in the area;
Based on the acquired progress status information, second information to be transmitted after recovery is identified from among the plurality of second information, and transmission of the identified second information is resumed. A plurality of second information included in the first information is transmitted to an information processing apparatus accessible to the storage device, and the transmission unit stores the transmitted second information in the storage device;
When the interruption is restored after the transmission of the second information is interrupted, it is an area in the storage device that is writable until the transmission of the plurality of second information is completed, and is used after the transmission is completed An acquisition unit for acquiring the progress status information from the information processing apparatus storing the progress status information for specifying the progress status of the storage of the plurality of second information in the area;
Based on the obtained progress status information, the second information to be transmitted after recovery among the plurality of second information is identified, and a restarting unit that resumes the transmission of the identified second information;
A transmission device comprising:

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