CN103810056A

CN103810056A - Method for obtaining consistent backup on Linux platform

Info

Publication number: CN103810056A
Application number: CN201210437244.7A
Authority: CN
Inventors: 濮文俊
Original assignee: NANJING YIJIZHI INFORMATION TECHNOLOGY Co Ltd
Current assignee: NANJING YIJIZHI INFORMATION TECHNOLOGY Co Ltd
Priority date: 2012-11-06
Filing date: 2012-11-06
Publication date: 2014-05-21

Abstract

The invention discloses a method for obtaining a consistent backup on a Linux platform. The method comprises the steps that files to be backed up are monitored, write operations of the files are intercepted in the backup process of the files, real-time data files of the files in the process of the write operations are obtained, mirror image data of the monitored files and real-time data of the monitored files are combined to form a backup according to the time sequence, and the backup generated at the moment is the consistent backup. According to the method for obtaining the consistent backup on the Linux platform, the requirement for a Linux operating system is low; due to the fact that an application module and a kernel module are used, the consistent backup of files or databases can be obtained on any Linux operating system, and the method for obtaining the consistent backup on the Linux platform is universal, and does not depend on any selectable configuration or technologies.

Description

A kind of method that obtains consistance backup on Linux platform

Technical field

The present invention relates to a kind of Computer Data Security field, particularly relate to a kind of method that obtains consistance backup on LINUX platform.

Background technology

Along with the department of computer science's widespread use of internet in every field of unifying, many government organs, company even individual more and more rely on computer data, therefore data security becomes one of important demand of information society, and data backup solves the key problem of data security just.

How what the technical program solved obtains consistance backup just on Linux platform, when user backups under some states, may there is application revising a certain file or data, Here it is makes backup time file in a state, and after having backed up, file is but in another state, and this recovering state database data hardly can be successful.

The operating system that Linux is a stable performance, powerful, efficiency is high.At present, the file backup instrument that Linux is traditional is as fairly simple in the command functions such as tar and cpio, be difficult to process the data backup of file system level, and can obtain the only snapping technique based on BTRFS, ZFS file system of consistance backup and the snapping technique of logic-based volume management (LVM).Ext3 or the ext4 file system of Linux acquiescence are not support snapshot, and logical volume management needs to install, and much Linux user may not carry out subregion and set up 1vm logical volume, therefore, for domestic consumer, this function of snapshot has very large use limitation.

Summary of the invention

The object of this invention is to provide a kind of method that obtains consistance backup on Linux platform.When user backups under some states, may have application revising a certain file or data, this just makes backup time file in a state, and after having backed up, file is but in another state, and this recovering state database data hardly can be successful.

For solving the problems of the technologies described above, the present invention takes following technical scheme:

Step 1: on Linux platform, file or the catalogue of needs monitoring are passed to administration module by application module, and send to administration module the order that starts or stop monitoring.

The monitoring module interception sys-write function of step 2:Linux kernel, is designated as OLDWRITE function by described former sys-write function, and the described sys-write function after interception is replaced with NEWWRITE function.

Step 3: in the time that user need to monitor, described application module notifies kernel to start monitoring by interface, after the write operation of file is intercepted and captured, described NEWWRITE function judges according to file handle whether described file is monitored file, if monitored file, catch operation moment, filename, start offset, the data content writing and the byte number of write operation, the real-time monitor message capturing is stored in real time data set, and last described file calls OLDWRITE function again; If not monitoring file, directly call OLDWRITE function, continue original process.

Step 4: when user program completes after the copy to monitoring file or catalogue, described application module notifies kernel to stop monitoring by interface.

Step 5: application module sets a file the mirror image data of above-mentioned monitoring file and real time data by the backup file of sequencing composition of real time data running time, and the backup now generating is exactly consistance backup.

Can find out from technique scheme, compared with the existing method that obtains consistance backup on Linux platform, the present invention has the following advantages:

The first, the present invention is lower to the requirement of (SuSE) Linux OS, by using application module and kernel module, can on any linux system, obtain the consistance backup of file or database, and method is general, do not rely on any can arrangement or technology.

The second, at present existing in Linux, must on the file system of support snapping technique or logical volume management, could obtain consistance backup.But ext3 or the ext4 file system of Linux acquiescence are not support snapshot, and logical volume management needs to install, and therefore, for domestic consumer, this function of snapshot has very large use limitation.

The 3rd, the snapshot of LVM adopts the mechanism of COW (Copy-On-Write), and, in the time that the data of former logical volume are carried out to write operation, original data block will be copied into the space of snapped volume distribution, and the flow direction of data is recorded in a table.If this logical volume exists multiple snapped volumes, original data block is the space that is copied into each snapped volume and distributes, and reduced system and write the efficiency of disk.

From the foregoing, the technology of the present invention has the advantages that operability is high, cost is low, efficiency is high.

Accompanying drawing explanation

Fig. 1 is general flow chart of the present invention.

Fig. 2 is the process flow diagram that monitoring module of the present invention is intercepted sys-write function and processed.

Fig. 3 is the process flow diagram of recording real-time data of the present invention.

Fig. 4 is the schematic diagram of synthetic consistance backup file in the present invention.

Embodiment

Below in conjunction with accompanying drawing, technical scheme of the present invention is elaborated.The present embodiment is implemented under take technical solution of the present invention as prerequisite, provided detailed embodiment and concrete operating process, but protection scope of the present invention is not limited to following embodiment.

First, user need to tell file or the catalogue that administration module need to be monitored by application module according to backup, and in the time that needs are monitored, application module sends the order that starts monitoring to administration module.In like manner, in the time not needing to monitor, application module sends the order that stops monitoring to administration module.For example, user backs up file between 11 o'clock 10, and therefore user can be chosen at 10 o'clock or before file be monitored, and when after Backup end, user can finish monitoring, also can continue as required monitoring.In addition, application module can add to administration module, delete the file that needs monitoring.

Notifying kernel module by interface when application module starts after monitoring, monitoring module interception kernel sys-write function, and sys-write function is processed, as shown in Figure 2, former sys-write function is designated as OLDWRITE function, and the described sys-write function after interception is replaced with NEWWRITE function.

As shown in Figure 3, after the write operation of file is intercepted and captured, and after the sys-write function of intercepting and capturing was carried out processing, NEWWRITE function judges according to file handle whether this file is monitored file, if not monitored file, call OLDWRITE function, the file of being intercepted and captured continues original process; If the file of being intercepted and captured is monitored file, catch the operation information of file, comprise operation moment, filename, start offset, the data content writing and byte number, the real-time monitor message capturing is stored in real time data set, last described file calls OLDWRITE function again, continues original process.Because monitor procedure is real-time, therefore can catch in real time the file that carries out write operation, every interception once forms real time data one time.Because operation information is very numerous and diverse, therefore to analyze operation information, the operation information of needs is recorded in real time data set, and real time data file is with the name of operation moment, when in chronological sequence order is synthesized consistance backup file so in the back, clear, easy operating, the consistance of assurance data.

After user completes the copy of a certain file, application module notifies kernel to stop monitoring by interface.If user need to continue monitoring to this file, described file is monitored in continuation as required, still according to the name of operation moment, while once backup, synthesizes consistance backup file at the real time data file after this forming on user carries out.

Finally, as shown in Figure 4, application module synthesizes a new backup file the mirror image data of monitoring file and real time data file set by running time der group, and the backup file of now producing is exactly consistance backup.Forming after a new consistance backup file, user can delete the image file producing and real time data file, increases Cyberspace.

Claims

1. a method that obtains consistance backup on Linux platform, is characterized in that comprising the following steps:

Step 1: file or the catalogue of needs monitoring are passed to administration module by application module, and send to administration module the order that starts or stop monitoring;

The monitoring module interception sys-write function of step 2:Linux kernel, is designated as OLDWRITE by described former sys-write function, and the described sys-write function after interception is replaced with NEWWRITE function;

Step 3: described application module notifies kernel to start monitoring by interface, after the write operation of file is intercepted and captured, described NEWWRITE function judges according to file handle whether described file is monitored file, if monitored file, catch operation moment, filename, start offset, the data content writing and the byte number of write operation, the real-time monitor message capturing is stored in real time data set, last described file calls OLDWRITE function again, if not monitoring file, directly call OLDWRITE function;

Step 4: when user program completes after the copy to monitoring file or catalogue, described application module notifies kernel to stop monitoring by interface;

Step 5: application module sets a file the mirror image data of above-mentioned monitoring file and real time data by the backup file of sequencing composition of time, and the backup now generating is exactly consistance backup.

2. a kind of method that obtains consistance backup on Linux platform described in claim 1, described Linux platform is lower to the requirement of (SuSE) Linux OS, default document system, does not need to possess snapshot functions, logical volume management and other complex configurations is installed.

3. a kind of method that obtains consistance backup on Linux platform described in claim 1, described real time data set is that the real-time monitor message capturing when file carries out write operation is monitored in storage, often intercept a write operation and carry out once record, its function class is like daily record.