JP3057771B2 - File system copy method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a file system used as an external storage device of a computer system.
In particular, the present invention relates to a copying method for backing up a file system.

[0002]

2. Description of the Related Art Conventionally, in this type of file system,
Data is backed up in case of system failure or erroneous operation. In the conventional backup method, when transferring the contents of a file, the existence of a failure is checked for each file or directory constituting the subtree, and only the part without the failure is transferred to the file system of the other party. .

[0003]

In the above-described copying method, a procedure of interpreting the tree structure of the file system on the file transfer side and then checking each file or directory for a failure is performed. I had to go through. This complicates the processing procedure when performing the transfer,
Particularly, when the capacity of the file to be copied is large, there is a problem that the transfer takes time.

The present invention simplifies the transfer procedure,
It is an object of the present invention to provide a file system copying method capable of reducing transfer time.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention relates to a file system copying method for copying tree-structured data composed of files and directories to another file system. Are transferred to the other file system in a lump. If the transfer fails, the data is transferred in units of subtrees one layer below the tree-structured data. On the other hand, the method is characterized in that data is further transferred in units of subtrees or files lower by one layer, and the above-described processing is repeated to specify a faulty file.

[0006] A partial tree is a collection of files or directories formed under a specific directory.

[0007]

First, when the transfer of the subtree of the upper hierarchy fails, the subtree of the lower hierarchy is transferred. At this time, if the failure file or directory is not included in the partial tree, the transfer is successful, and the copying of the partial tree is completed.
On the other hand, when a failure file or the like is included in the partial tree, the transfer fails, so the partial tree further lower in the hierarchy is transferred. In this way, by repeating the process of transferring the lower subtree depending on whether or not the transfer is possible, it is possible to reach the faulty file or directory. Therefore, a file or directory having a failure can be specified without checking each file or directory at the time of transfer.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a file copying method of a file system according to the present invention will be described below.

FIG. 1 is a block diagram showing one embodiment of a file system for realizing a file copying system according to the present invention.

In FIG. 1, reference numeral 1 denotes a file system on the file sending side, 2 denotes a CPU for processing data of the file system 1, 3 denotes a file system on the file receiving side, and 4 denotes data on the file system 3. C that performs data processing
PU 5 is a network to which CPU 2 and CPU 4 are connected.
It is configured so that data transfer between the CPU 2 and the CPU 4 is possible. The CPU 2 and the CPU 2
4 may be the same.

In FIG. 1, when a partial tree is transferred from the file system 1 to the file system 3 collectively,
First, the CPU 2 converts the data into a sequential bit string 6.
Convert to Next, the CPU 2 transfers the bit string 6 from the CPU 2 to the CPU 4 in the same format. In CPU4,
The original subtree is reconstructed from the bit string 6 and stored in the file system 3.

FIG. 2 is a conceptual diagram schematically showing the tree structure of the file system 1. As shown in FIG. In this figure, the directory is represented by an ellipse and the file is represented by a rectangle, and it is assumed that the hatched file F has an obstacle. When transferring such a file system, first, the entire subtree under the directory A is transferred. However, in this case, the transfer fails because the file F having the failure is included. Next, the directory tree is moved to a level one level below the directory A, and the subtrees below the directories B and C are transferred. The transfer succeeds because the subtree under the directory C does not include a file having a failure. On the other hand, the transfer fails because the subtree under the directory B contains the file F. Next, it moves to a level one level below the directory B, and transfers the subtrees below the directories D and E. Here, the transfer fails because the subtree below the directory D includes the file F, but the transfer succeeds because the subtree below the directory E does not include a file having a failure. Finally, transfer is attempted at a level one level below the directory D. Here, the transfer of the file G succeeds, but the file F fails because of a failure. Therefore, the file F with the fault at this point
Can be specified. If there is a failure in the directory, the failure in the directory is recovered and the transfer is attempted again, whereby the subtree under the directory can be transferred.

Next, the processing procedure of the CPU 2 for specifying the faulty part of the partial tree shown in FIG. 2 will be described with reference to FIG. 1 based on the flowchart of FIG.

First, the CPU 2 transfers a subtree below the directory in the highest hierarchy (step 101), and determines whether or not the transfer was successful (step 102). Here, if the transfer has failed, the directory is moved down one level (step 103), and the first directory is accessed (step 104). Then, it is determined whether or not the access is successful (step 105). If the access is not possible, it is determined that the directory has a failure and the user is notified (step 106). Whether the subtree has been transferred and whether the directory has been accessed are determined based on the presence or absence of error information.

If the directory can be accessed in step 105, the subtree under the directory is transferred (step 107), and it is determined whether or not the transfer was successful (step 108). Here, when the partial tree has been successfully transferred, it is determined whether or not the partial trees under all directories at the same level have been transferred (step 1).
09) If all subtrees have not been transferred, access is made to the next directory at the same level (step 11).
0), and return to step 105. If the subtree cannot be transferred in step 108, it is determined whether or not the subtree is composed only of files (step 111). If the partial tree is composed of only the file, it is determined that the file has a failure, and the user is notified (step 112).
If the subtree is not only a file, step 1
Returning to 03, the above process is repeated until a faulty file or directory is reached.

According to the above-described processing, only the portion of the file system shown in FIG. 2 where no failure has occurred can be transferred (copied) to the system of the other party. If a copy of the file system before the failure occurred was stored in the file system of the other party, the failed part (file or directory) that could not be transferred is the same part of the file system copied before the failure occurred. By copying, a copy closer to the original file system can be created.

Further, in the above-described embodiment, the case where the transfer is performed from the subtree below the directory in the highest hierarchy of the tree structure is described, but the transfer is performed from the subtree below the directory in the middle or lower hierarchy. You may do so.

[0018]

As described above, in the file system copying method according to the present invention, when the transfer of the subtree fails, the process of transferring the subtree of the next lower hierarchy level is performed continuously. As a result, since a file or directory in which a failure has occurred is specified, it is not necessary to interpret the tree structure before the transfer or check for a failure in the file or directory, thereby simplifying the processing procedure at the time of copying. . Therefore, even when the file capacity is large, the time required for copying is greatly reduced, and the copying efficiency can be further improved.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of a file system for realizing a copying method according to the present invention.

FIG. 2 is a conceptual diagram schematically showing a tree structure of the file system shown in FIG. 1;

FIG. 3 is a flowchart showing a processing procedure of a CPU when a faulty part of a partial tree is specified.

[Explanation of symbols]

 1, 3, file system 2, 4, CPU 6, bit sequence

Claims (1)

(57) [Claims] 1. A file system copying method for copying tree-structured data composed of files and directories to another file system, wherein the tree-structured data is collectively transferred to the other file system. If the transfer fails, the data is transferred in units of subtrees one level below the tree-structured data. A file system copying method characterized in that a data file is transferred and a faulty file is specified by repeating the above processing.