TWI536161B - Backup method, recovery method and computer, computer program product and computer readable recording medium thereof - Google Patents

Description

Backup method, restoration method and computer, computer program product and computer readable recording medium

The invention relates to a disk partition backup and restoration technology, in particular to a technical solution for backup and restoration using snapshots.

A conventional backup and restore program installed in a computer, such as Norton Ghost provided by Symantec, generates an image file for the disk area of the computer during the backup operation.

When a disaster such as data loss or poisoning occurs in the disk area, the conventional backup and restore program can use the image file to perform a restore operation, and the disk area is restored to the state when the image file was created. So that the computer can function as it was at the time.

The above backup operation is based on block ("block" refers to the cluster referred to in the FAT file system, or the block, or sector) in the Ext2 file system, and the magnetic to be backed up. The data in the disc area is read out one block at a time, and is written one by one into the image file previously established in another disk area. However, as long as one of the blocks is damaged, the image cannot be utilized for the above-described restore operation.

Furthermore, the above image file must be stored in another disk area created in advance, and the data to be backed up cannot be stored in the same disk area, which means that the conventional backup and restore program cannot be in a disk area. The data is backed up to this disk area. For example, the data in the C slot (C:\) of a hard disk cannot be backed up to other free space in the C slot.

The present invention provides a backup method for backing up files in a backup source to a backup destination. The method is mainly to first create a corresponding snapshot for the backup source, so that those are not changed after the snapshot is established or The deleted files have corresponding shadow copies in the snapshot, and then read the shadow files and the files in the files that remain intact after the snapshot is created, and will The read data is written to an image file (Image File) previously established in the backup destination. In this way, the backup operation of backing up the files in the backup source to the backup destination is completed. The backup source and the backup destination may be the same disk partition; the snapshot may be established by a shadow copy service.

More specifically, the backup method of the present invention includes, but is not limited to, searching for a file in the backup source to obtain a file list, establishing a corresponding snapshot for the backup source, and establishing a backup in the backup destination. An image file, and opening the image file; performing a write job for each file recorded in the file list; the writing operation includes determining whether a corresponding shadow copy of a file recorded in the file list exists in the file In the snapshot; if the corresponding shadow copy of the file exists in the snapshot, the shadow copy corresponding to the file is opened, and the data in the shadow copy is read by reading the file, and the read data is read The data is written into the image file; if the corresponding shadow copy of the file does not exist in the snapshot, the file is opened, and the data in the file is read by reading the file, and the read data is read. The image file is written; the write job is repeated until the file recorded in the file list has been written into the image file after the write operation. At this point, the backup operation of backing up the files in the backup source to the backup destination is completed.

In the above backup method of the present invention, if the snapshot is not successfully established, and the selected backup source includes a system disk area, an error message is generated, and the step of establishing the image file and the subsequent steps are stopped.

In the above backup method of the present invention, if the shadow copy is successfully opened, subsequent reading and writing operations are performed; if the opening fails, the backup source is used to read the backup source one by one. Stores the data in the block of the shadow copy and writes the read data to the image. Similarly, in the above backup method of the present invention, if the file is successfully opened, subsequent read and write operations are performed; if the open fails, the selected block is read one by one by reading the block. The resources in the block used to store the file in the backup source And write the read data to the image file.

In the above backup method of the present invention, after opening the image file or before closing the image file, a file write list is also written in the image file, and the file write list records that the image file is written. Information about all the files in the file, the related information contains the location of the contents of each file in the image file.

The present invention also provides a method for restoring, after a user completes a backup operation of backing up files in the backup source to the backup destination by the above backup method, the restore method includes from the backup Find the file that was modified after the snapshot was created in the source, and use the image file to restore the modified file to the state at the time the snapshot was created. The restoration method further includes finding an archive from the backup source that is deleted after the snapshot is established, and using the image file to restore the deleted archives to the backup source. Preferably, the restoration method further comprises finding and deleting the file added to the backup source after the snapshot is established. In addition, the restoration method further includes saving the modified files to another location or renaming the modified files before using the image file to restore the modified files.

The present invention further provides a computer program product that, when loaded and executed by a computer, can perform any of the methods described above. The present invention also provides a computer readable recording medium storing an application program, and when a computer is loaded into the application and executed, any of the above methods can be completed. Further, the present invention provides a computer having a processing unit and a hard disk. The hard disk stores at least one operating system and an application program, and the operating system provides a service for establishing a corresponding snapshot for the hard disk. After the processing unit is loaded into the application and executed, the method of any one of claims 1 to 10 may be completed, wherein one or more disk partitions of the hard disk are as described in the method. The source of the backup, the backup destination described in the method is a disk partition in the hard disk or a disk partition in another hard disk connected to the computer.

Compared with the prior art, the backup method of the present invention writes files in a backup source one by one into the image file, which is a file-based backup operation, which is different from the prior art block-based backup. Operation. In addition, the fast restore method of the present invention restores only those files that are deleted after the snapshot is created, and does not need to restore all the files in the backup source when the snapshot is created. Therefore, the restore speed is fast and superior to the prior art.

1‧‧‧ computer

10‧‧‧ Hard disk

100‧‧‧Disk area

101‧‧‧Operating system

102‧‧‧ Shadow Copy Service

11‧‧‧Processing unit

12‧‧‧ display

13‧‧‧Input device

2‧‧‧Backup module

3‧‧‧Restore module

The first figure is a system block diagram of a preferred embodiment of the computer of the present invention.

The second drawing is a flow chart of a preferred embodiment of the backup method of the present invention.

The computer program product of the present invention is installed in a computer 1 shown in the first figure, and includes a backup module 2, and preferably a restoration module 3. The computer 1 can be a desktop personal computer or a notebook computer or other type of computer. The computer 1 includes a hard disk 10, a processing unit 11, a display 12, and an input device 13 (e.g., a mouse and/or a keyboard), and at least one operating system 101, such as a Windows 7 or 8 operating system, has been installed. The processing unit 11 includes one or more central processing units (CPUs) and their associated circuits (e.g., various memories, chipsets, etc.) that can load and execute the operating system 101 and various applications installed in the computer 1. Program.

The hard disk 10 can be a built-in hard disk in the computer 1, or an external hard disk (such as a USB hard disk or a network hard disk) connected to the computer 1. The hard disk 10 has a plurality of magnetic disk areas 100, such as a commonly known C slot (C:\), D slot (D:\), E slot (E:\), etc., and the hard disk 10 may have only one. The disk area, for example, only the C slot. The aforementioned disk area generally refers to a partition called a basic hard disk, or a volume called a dynamic hard disk. A plurality of files are stored in each disk area, and the windows operating system is taken as an example. The files include, but are not limited to, general folders and general files that can be viewed by using the file manager function of the operating system, and the files are utilized. Hidden folders and hidden files that cannot be viewed by the general manager function, system files related to the operating system, and other types of files. The disk area 100 used as the C slot is an area for storing the file associated with the operating system 101, and is generally referred to as a system disk area.

When the processing unit 11 of the computer 1 loads and executes the code of the backup module 2, one of the backup methods of the present invention can be completed. The second figure shows an execution flow of a preferred embodiment of the backup method, which includes the following steps: As shown in step a, a backup menu is displayed on the display 12 of the computer 1, and a user selects a backup source and a backup destination from the backup menu. The backup source may be one or more disks 100 in the hard disk 10. The backup destination may be a certain disk area 100 in the hard disk 10, or a disk in another hard disk. . The user is making a selection At the time of selection, one or more extents 100 can be selected at one time as the backup source. This step can be omitted if the backup source and backup destination have been determined in advance and are not allowed to change.

As shown in step b, search for files in the selected backup source and create a file list based on the search results. The search is to search back all the files and folders starting from the root directory of the selected backup source. The file list records information about each file in the backup source, such as file name, file path, creation date, modification date, file size, file attributes, security, and the like. Preferably, information related to the computer 1, the hard disk 10, and the disk area 100, such as BIOS information, is also recorded.

As shown in step c, a corresponding snapshot is created for the selected backup source. For example, if the disk area in the selected backup source has only the C slot, a snapshot of the C slot is established correspondingly. If the disk area in the selected backup source has a C slot and a D slot, respectively, the C slot is established. Snapshots and snapshots of D slots, and so on. This snapshot was created to ensure data consistency. Data consistency means that the data backed up during the backup process is the same as the data in the backup source when the snapshot was created. Even if the file is modified or deleted during the backup process, it is not affected.

Preferably, the snapshot can be established by using the Volume Shadow Copy Service (VSS) provided by the Windows operating system, but not limited thereto, and any other data consistency can be used. mechanism. In any case, once the snapshot is established, it is equivalent to establishing a corresponding restore point for the selected backup source. In this example, the selected backup source will enter a normal state at this time. The state of "copy-on-write". In the state of copying at the time of writing, as long as any file is changed (by being modified and stored) or deleted due to the call of another application, a copy is copied before it is changed or deleted. A shadow copy obtained from any of the files will be stored in the snapshot. The shadow copy is a file of the same file, that is, a copy created under the snapshot. Since the file should be any). Therefore, the file that has been moved or deleted after the snapshot is created will have a corresponding shadow copy saved in the snapshot, and the file that remains intact after the snapshot is created will not have a corresponding shadow copy. . Therefore, for the restore point (the point at which the snapshot was created), the files that should be backed up are those that remain intact after the snapshot is created, and those shadow copies that are in the snapshot, and the subsequent steps. Will elaborate on the preparation of these files Process.

As shown in step d, an image file is created in the selected backup destination, and the image file is opened. However, the step d is not limited to being performed after the step c. For example, it may be performed before the step b or simultaneously with the step b, or may be performed before the step c or simultaneously with the step c.

Then, a write job shown in step e is performed for each file recorded in the file list, and the write job includes but is not limited to the following steps e1 to e5: E1) Determine whether a file in the file list has a corresponding shadow copy present in the snapshot.

If the corresponding shadow copy of the file exists in the snapshot, it means that the file has been changed or deleted after the snapshot is created, and cannot be used as the basis for the original hard disk 10 in the future. As shown in the step, the shadow copy corresponding to the file is opened, and then, as shown in step e3, the data in the shadow copy is read by reading the file, and the read data is written into the image file. . Preferably, each of the aforementioned data is compressed and encrypted before being written into the image file.

However, if there is no corresponding shadow copy of the file in the snapshot, it means that the file has not been changed after the snapshot is created, and can be used as the basis for the hard disk 10 in the future. At this time, as in step e4. Show, open the file, and then, as shown in step e5, read the data in the file by reading the file, and write the read data to the image file.

Next, as shown in step f, the write operation shown in the above e step is repeated until each file recorded in the file list has been subjected to the write job and is written to the image file.

Finally, as shown in step g, close the image and delete the snapshot (however, this g step is not necessary, because the image will be automatically closed when the computer 1 is shut down, the snapshot will be automatically deleted) . At this time, the selected backup source is thus returned to the normal state from the state of copying at the time of writing. At this point, the backup operation of the selected backup source is completed, so that the files in the selected backup source are backed up to the image in the backup destination, and the contents of the archived files are followed by Before the snapshot is created, even in the above-mentioned writing process, some files have been changed or deleted due to the call of other applications, and the files can still be before or before the transaction is deleted. The information is completely backed up. Wherein, after opening the image file, or before closing the image file, an archive write list is also written in the image file, and the file write list records all the files written in the image file. Related information, the relevant information is mainly the location of the file content (including file attributes) in the image file. In the future, when the restore operation is performed according to the image file, the files in the image file can be written into the designated hard disk (ie, the restore destination) one by one according to the file write list.

As can be seen from the above description, as a result of the operation of the computer 1 at a certain time according to the backup method, an image file corresponding to a certain time is generated at the backup destination. The image file corresponding to each moment represents a restore point. When the user wants to restore the hard disk 10 of the computer 1 to a certain time state, it is only necessary to use the image file corresponding to the certain time to perform the operation, so that the hard disk 10 can be quickly restored to the state. The state of the moment at a certain moment. The user can also use the image file corresponding to the certain moment to write the files in the hard disk to another hard disk designated by the user, so that the file storage status of the other hard disk is the same as that of the hard disk. The current storage status of the hard disk 10 at that moment.

Preferably, after the step c above, it is further determined whether the snapshot is successfully established. If the determination result is “Yes”, indicating that the snapshot has been successfully established, proceeding to the step d (ie, establishing the image file), However, if the determination result is "No", indicating that the snapshot establishment fails, it continues to determine whether the selected backup source includes the system disk area in which the operating system 101 is stored. If the determination result is "No", the selected backup is indicated. If the source does not include the system disk area, proceed to step d above. However, if the result of the determination is "Yes", it indicates that the selected backup source contains the system disk area. At this time, in order to ensure data consistency, it is generated. The "backup failed" error message is on the display 12 and the process of the backup method of the present invention is terminated, i.e., d and its subsequent steps are no longer performed. In this way, the foregoing determining step can ensure that the image file created for the system disk area does not have data inconsistency, and the image file area can be restored to the aforementioned snapshot by using the image file in the future. The state at the time of establishment.

Preferably, in the above step e3, after opening the shadow copy, it is determined whether the opening is successful, and if the shadow copy is successfully opened, subsequent reading and writing operations are performed, however, if the opening fails, Reading a block (referred to as a Cluster, block, or sector), reading the data in the block of the selected backup source for storing the shadow copy one by one, and writing the read data to the image In the file. Preferably, each time the data is read, Both are compressed and encrypted before being written to the image.

Preferably, in the step e5, after the file is opened, it is determined whether the opening is successful. If the file is successfully opened, subsequent reading and writing operations are performed. However, if the opening fails, the reading is performed. The block (referred to as Cluster, block, or sector) reads the data in the block of the selected backup source for storing the file one by one, and writes the read data into the image file. Preferably, each time the data is read, it is compressed and encrypted before being written into the image file.

It should be noted that for different file systems, different ways are needed to find the block of the file or shadow copy. For example, for the FTA32 file system, the DBR (DOS Boot Record) block is first read to obtain the root directory and File Allocation Table (FAT), and then the file or shadow copy is obtained from the file allocation table. Clusters, then, get the blocks occupied by the clusters. The material stored in these blocks is the data in the file or shadow copy.

For another example, for the NTFS file system, the DBR block is first read, the main file table (MFT) start block is obtained, and the MFT item of the file or shadow copy is searched from the MFT block. The obtained MFT item obtains the basic attribute and data stream attribute (DataRun) of the file or shadow copy, and obtains the block of the file or shadow copy from the stream attribute. The material stored in these blocks is the data in the file or shadow copy.

As can be seen from the above description, the above backup method of the present invention cannot read the files in the manner of reading the files and write them into the above image file, but can use the file or the shadow copy. The way the blocks are read, the data is read from the block in which the file or shadow copy is stored and written to the above image.

The backup method of the present invention writes files in a backup source one by one into the image file, which is a file-based backup operation, which is different from the prior art block-based backup operation. Therefore, even if a certain block of the hard disk 10 is damaged, only one file is damaged, and the entire image cannot be used for the restoration operation.

Furthermore, since the backup method of the present invention is a file-based backup operation, the backup method of the present invention allows the backup source to be the same disk partition 100 as the backup destination, as long as its free space is sufficient. Large, for example, backing up data in each of the C slots to an image file created in the free space within the C slot.

In addition, after the computer 1 loads and executes the backup module 2 to complete the backup method, the restoration module 2 can be used to restore the file backed up according to the backup method to a restoration purpose from the image file. Ground (referring to a certain disk area, at this time, the image file is stored in another disk area or called a restore source), for example, restored to the hard disk 10 (that is, the backup source mentioned above) or another hard dish. More specifically, when the processing unit 11 of the computer 1 loads and executes the code of the restoration module 3, one of the reduction methods of the present invention can be completed. In an example, the restoration method is a normal restoration. A method comprising formatting the restore destination. Then, after the restoration destination completes formatting, according to the file write list in the image file, the file in the image file is restored to the restore destination in the form of one file and one file. At this point, the normal restoration method is completed. At this time, the file status in the restore destination is the same as the file status when the backup source establishes the snapshot.

After the above backup method is completed, the file status in the backup source may be different from the file status in the backup source when the snapshot is created because the user subsequently performs the modification action or the delete action. If necessary, the user can use the image file built above to perform the restore operation. For the backup source, the file that has not been moved after the snapshot is created does not need to be restored. It is only modified after the snapshot is created, and the image file needs to be restored. If you think that the files that were deleted after the snapshot was created still need to be saved, you can use the image file to restore them. In addition, files added after the snapshot is created can be selected to be retained or deleted. If you want to restore the backup source to the file state when the snapshot was created, then the file that was modified and deleted after the snapshot was created should be restored using the image file and will be updated after the snapshot is created. The added files should also be deleted. According to the foregoing principles, the present invention provides another method for restoring, which is a fast restore method, including finding an archive from the backup source that is modified after the snapshot is established, and using the image file to The modified files are restored to the state at the time the snapshot was created. The method further includes finding an archive from the backup source that is deleted after the snapshot is established, and using the image file to restore the deleted archive to the backup source. Preferably, the method includes finding and deleting the file added to the backup source after the snapshot is established. Additionally, the method includes saving the modified files to another location or renaming the modified files before restoring the modified files using the image file. Wherein, the above file write list and a file list can be used to find out the file that is modified, deleted or added after the snapshot is created. case. The file list is obtained by performing file search on the backup source, and the content thereof is substantially the same as the file list, or other methods may be used to find the file that is modified, deleted or added after the snapshot is created. I will not repeat them.

Since the fast restore method of the present invention restores only those files that are changed or deleted after the snapshot is created, it is not necessary to restore all the files in the backup source when the snapshot is created, and therefore, the restore speed is fast and is in the same category. Deep advantage.

Claims (14)

A backup method is used for backing up files in a backup source to a backup destination. The backup method includes: searching for files in the backup source to obtain a file list, and the file list records each searched Corresponding information of a file; establishing a corresponding snapshot for the backup source; establishing an image file in the backup destination, and opening the image file; performing a write operation for each file recorded in the file list, The writing operation includes: determining whether a corresponding shadow copy of a file recorded in the file list exists in the snapshot; if the corresponding shadow copy of the file exists in the snapshot, opening the shadow corresponding to the file Copying, reading the data in the shadow copy by reading the file, and writing the read data to the image file; if the file does not have a corresponding shadow copy in the snapshot, the file is opened And reading the data in the file by reading the file, and writing the read data to the image file; repeating the writing operation, Files to the file list described have experienced this write operation is written to the image profile so far. The backup method of claim 1, wherein if the snapshot is not successfully established, and the selected backup source includes a system disk area, an error message is generated, and the execution of the image file is stopped. Steps and subsequent steps. The backup method of claim 1, wherein if the shadow copy is successfully opened, subsequent reading and writing operations are performed; if the opening fails, the block is read one by one. The data in the block of the backup source for storing the shadow copy is taken, and the read data is written into the image file. The backup method of claim 1, wherein if the file is successfully opened, subsequent reading and writing operations are performed; if the opening fails, the reading is performed one by one by reading the block. The selected backup source is used to store the data in the block of the file, and the read data is written into the image file. The backup method of claim 1, wherein the backup source is the same disk partition as the backup destination. The backup method of claim 1, wherein the snapshot is established by a shadow copy service. The backup method according to any one of claims 1 to 6, wherein after the image file is opened or before the image file is closed, a file write list is also written in the image file, and the file is written. The entry list records information about all the files written in the image file, and the related information includes the location of the contents of each file in the image file. A method for restoring is performed after performing the backup method as described in claim 7 of the patent application scope, the method comprising: finding an archive from the backup source that is modified after the snapshot is established, and The image file is used to restore the modified file to the state at the time the snapshot was created. The method for restoring, as described in claim 8, includes: finding an archive from the backup source that is deleted after the snapshot is created, and using the image file to restore the deleted file to the backup. source. The restoration method described in claim 8 of the patent scope includes: finding and deleting the file added to the backup source after the snapshot is established. The method for restoring, as described in claim 8, includes: saving the modified files to another location or renaming the modified files before using the image file to restore the modified files. A computer program product, which can be loaded and executed by a computer, and can be completed as described in any one of claims 1 to 11. A computer readable recording medium storing an application program, and when a computer is loaded into the application and executed, the method according to any one of claims 1 to 11 can be completed. A computer having a processing unit and a hard disk, the hard disk storing at least one operating system and an application program, the operating system providing a service for establishing a corresponding snapshot for the hard disk, when the processing unit loads the application And the method of any one of claims 1 to 11, wherein one or more disk partitions of the hard disk are used as a backup source of the method, and the method is The backup destination is the disk partition in the hard disk or the disk partition in another hard disk connected to the computer.