JPH11316700A - System and method for data backup - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce work burden at the time of recovering data. SOLUTION: A data transfer device (reconstituted data storage means/data transfer means) 4 is provided at a backup server 2 connected to an information processor (storage device) 1 through a network. Backup data received from the information processor 1 through a network 6 are successively stored in a tape unit (external data storage means) 3, and source data reconstituted from these backup data are stored in the data transfer device 4 as reconstituted data. Besides, a data transfer device (data transfer means) 5 is provided on the side of the information processor 1, and the reconstituted data stored in the data transfer device 4 are transferred through a network 7 to the information processor 1 so that data can be recovered.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a data backup system and method, and more particularly to a data backup system and method for backing up original data in a storage device connected to an information processing device such as a computer.

[0002]

2. Description of the Related Art With the development of the information society, it is essential to perform a large amount of information processing using an information processing device such as a computer. The information processing apparatus performs a process of storing a large amount of data in a storage device, reading and processing necessary data, and writing the data to the storage device again. As the storage device, for example, a hard disk device having a large storage capacity and capable of high-speed access is used, but such a storage device may be damaged by an impact, an unexpected power failure, or the like.

When the storage device is damaged, not only can data stored in the damaged portion not be read correctly, but also all the data stored in the storage device cannot be accessed because the storage device cannot be accessed. May disappear. In order to prepare for such an accident, it is desirable to back up the data stored in the storage device to another storage medium, especially if the data stored in the storage device is important. Backup is mandatory.

A tape device is usually used for data backup of a storage device. The tape device has a feature that the data storage capacity is very large and the cost is lower than other storage media. An inter-device interface called a SCSI interface is often used to connect the information processing device to the tape device. This SCSI interface is an interface for connecting an information processing device and a peripheral device such as a tape device.
Since the data transfer speed is relatively high, this interface is used for general purposes.

[0005] However, it is difficult for the SCSI interface to increase the connection distance due to the characteristics of the interface. Therefore, in the event of a widespread disaster such as a fire or earthquake, there is a high possibility that the information processing device and peripheral devices installed near it will be lost or malfunction at the same time, and the original data (original data) stored in the storage device will be lost. There is a risk that the backup data stored in the tape device will be lost at the same time.

In order to solve such a problem, a method of storing backup data in a place remote from the information processing apparatus has been adopted. In this method, as shown in FIG. 4, a backup server 2 is connected to an information processing device (storage device) 1 via a network 6, and backup is performed on a tape device 3 connected to the backup server 2.

By installing the backup server 2 at a location remote from the information processing apparatus 1, it is possible to back up data and at the same time to store backup data at a location away from the information processing apparatus 1. The data backup is performed to restore the storage device to its original state based on the backup data when the data stored in the storage device of the information processing device 1 is lost for some reason.

Therefore, a data transfer function (data recovery) from the tape device 3 to the information processing device may be provided as well as a data transfer function (data backup) from the information processing device 1 to the tape device 3. In the method shown in FIG. 4 described above, backup data can be transferred from the backup server 2 to the information processing device 1 via the network 6,
Lost data can be restored in a relatively short time.

[0009] However, the storage capacity of storage devices is increasing year by year, and the data capacity for backup is enormous. Therefore, when data transfer (backup) between the information processing apparatus 1 and the backup server 2 is performed using a normal information processing network such as a telephone line or a LAN, the amount of data that can be transferred per unit time is limited, and Takes a very long time.

Further, by occupying the network 6 for a long time for data backup, it is expected that the efficiency of other information processing work using the network 6 will be reduced. For this reason, there is a need for a method of devising a data backup method to reduce the time required for data backup.

The data backup method includes a full backup for backing up all contents of the storage device or all necessary files, an incremental backup for backing up only files changed since the previous backup, and a reference time point. For example, a differential backup in which all changed files are backed up every time since a full backup was performed may be considered.

Here, the method of incremental backup and differential backup will be described with reference to FIGS. FIG. 5 is an explanatory diagram showing an incremental backup method, and FIG. 6 is an explanatory diagram showing a differential backup method. In the following, a full backup for backing up the original data in the storage device as it is is performed once every few days, and an incremental backup or a differential backup is performed once a day during the full backup. .

In FIGS. 5 and 6, a full backup is performed on the first day, and FileA is updated on the second day.
A 'is generated, FileC is newly created on the third day, FileB is updated on the fourth day, and FileB' is generated. In the drawings described below, hatched portions indicate changed portions, and shaded portions indicate backup targets.

First, in the incremental backup method shown in FIG.
The full backup on the first day creates a tape 11 with the same contents as the original data, and thereafter, the incremental backup
On the second day, a tape 12 made of FileA 'is generated,
On the third day, a tape 13 made of FileC is generated.
On the day, a tape 14 made of FileB 'is generated and backed up.

On the other hand, in the differential backup method shown in FIG.
A full backup on the first day creates a tape 11 with the same contents as the original data.
On the second day, a tape 12 made of FileA 'is generated,
On the third day, tape 1 consisting of FileA 'and FileC
3 are generated, and on the fourth day, FileA ', FileC, and F
ileB ′ is generated and backed up.

When data is restored after data backup in this way, the original data at the time of the last full backup is reconstructed based on the tape 11 on which the full backup was performed first. After that, the data updated after the full backup is restored.

Here, in the incremental backup method, in order to recover data, as shown in FIG.
And the tapes 12 to 14 must be properly combined to restore each file. On the other hand, in the differential backup method, as shown in FIG. 8, two tapes, a tape 11 for which a full backup was performed and a tape 14 for which a backup was performed on the last day (the fourth day), are required.

[0018]

Therefore, in such a conventional backup system and method, when data is restored, the data at the time of the last full backup is used regardless of whether the incremental backup method or the differential backup method is used. It is necessary to appropriately combine the tape 11 with a tape backed up thereafter.
For this reason, tapes required for data recovery must be properly selected from storage locations without error, and tapes must be replaced.
There is a problem that the work load required for data recovery cannot be reduced. The present invention has been made to solve such a problem, and an object of the present invention is to provide a data backup system and a data backup method that can reduce a work load at the time of data recovery.

[0019]

In order to achieve the above object, a data backup system and method according to the present invention are connected to a storage device via a first network and stored in the storage device. A backup server that receives backup data generated from the data via a first network; and an external data storage unit that is connected to the backup server and that sequentially stores the backup data received by the backup server. The original data reconstructed on the basis of the backup data received in step (1) is stored in the reconstructed data storage means as reconstructed data. Therefore, each time backup is performed, the latest state in the storage device is automatically reconstructed in the reconstructed data storage means based on the backup data.

The original data in the storage device is restored by transferring the reconstructed data stored in the reconstructed data storage means to the storage device via the first network or a different second network. Because it was
At the time of data recovery, the reconstructed data is transferred via an appropriate network, and the data in the storage device is reconstructed. Also, of the original data in the storage device, only the files that have been changed since the previous backup are set as backup data. In addition, all files that have changed since the reference backup time point are used as backup data.

[0021]

Next, the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a data backup system according to an embodiment of the present invention. In the figure, the same or equivalent parts as those described above (see FIG. 4) are denoted by the same reference numerals.

In the present invention, a tape device (external data storage means) 3 for storing a large amount of data is connected to the backup server 2 and a data transfer device (reconstructed data storage means / Data transfer means) 4 is connected, and the original data in the information processing device (storage device) 1 is sequentially reconstructed based on the backup data received by the backup server 2 and stored in the data transfer device 4 as reconstructed data. It is something to do.

A data transfer device (data transfer means) 5 is provided on the information processing device 1 side, is connected to the data transfer device 4 via a high-speed and large-capacity network 7, and is stored in the data transfer device 4. Information processing device 1 for reconstructed data
To restore the original data. By using a high-speed and large-capacity network for data backup and recovery, data backup and data recovery can be performed in a short time.

Next, referring to FIG. 2, the operation of the present invention will be described by taking as an example the case where an incremental backup method is used. FIG. 2 is an explanatory diagram showing the operation of the present invention when the incremental backup method is used. With data backup,
Data backup is performed based on a preset schedule using a method such as a full backup and an incremental backup (differential backup) via a network 6 including an information processing network such as a normal LAN.

At this time, the backup data is stored in the tape device 3. The tape device 3 accumulates backup data sequentially and does not perform rewriting. As a result, all the backup data including the past history can be saved similarly to the conventional backup method, and the state in the storage device of the information processing device 1 at an arbitrary time can be restored.

After data is backed up to the tape device 3, data is also written to the data transfer device 4 to reconstruct the same state as the storage device of the information processing device 1 in the data transfer device 4. Here, a case is described in which data is written to the data transfer device 4 (disk rebuilding) after backup data is stored in the tape device 3, but data storage in the data transfer device 4 and data storage in the tape device 3 are performed. The order and timing of data accumulation may be arbitrary.

In the following, a full backup for backing up the original data in the storage device as it is is performed once every few days, and an incremental backup is performed once a day during the full backup. In the drawings described below, hatched portions indicate changed portions, and shaded portions indicate backup targets.

In FIG. 2, a tape 11 having the same contents as the original data is generated by full backup on the first day.
After that, FileA 'on the second day by incremental backup
, A tape 13 made of FileC is created on the third day, and a tape 14 made of FileB 'is created and backed up on the fourth day. In parallel with this, the backup data is overwritten and stored in the data transfer device 4 in file units, and the latest original data is sequentially reconstructed.

That is, FileA and Fil on the first day
eB accumulates, and FileA 'and File
B, FileA ', FileB and FileC are stored on the third day, and FileA', Fi are stored on the fourth day.
leB 'and FileC are stored. By performing such data backup, the data transfer device 4
The contents of the reconstructed data reconstructed in the information processing device 1
Of the storage device at the time of the last backup.

Next, with reference to FIG. 3, the operation of the present invention will be described by taking a case where a differential backup method is used as an example. FIG. 3 is an explanatory diagram showing the operation of the present invention when the differential backup method is used. In this case, the tape 11 having the same contents as the original data is first generated by the full backup on the first day, and thereafter the F11 is created on the second day by the differential backup.
The tape 12 consisting of ileA 'is generated.

On the third day, FileA 'and File
C on the fourth day.
Tape 14 consisting of A ', FileC and FileB'
Is generated and backed up. In parallel with this, the backup data is overwritten and stored in the data transfer device 4 in file units, and the latest original data is sequentially reconstructed.

That is, FileA and Fil on the first day
eB accumulates, and FileA 'and File
B, FileA ', FileB and FileC are stored on the third day, and FileA', Fi are stored on the fourth day.
leB 'and FileC are stored. By performing such data backup, the data transfer device 4
The contents of the reconstructed data reconstructed in the information processing device 1
Of the storage device at the time of the last backup.

Therefore, in any of the backup methods, at the time of data restoration, all or any data stored in the data transfer device 4 is transferred to the information processing device 1.
The state of the storage device of the information processing apparatus 1 at the time when the data backup was last performed can be restored. As a result, compared to the conventional data backup method, it is necessary to select the combination of tapes necessary for data recovery properly from the storage location without error, replace the tape, and search the data in the tape as necessary. The work load at the time of data recovery is reduced.

In order to restore the state at an arbitrary point in the past, the backup data stored in the tape generated by the tape device 3 may be used. Further, any method may be used as the backup method, but by using the incremental backup, the amount of backup data for each time is the smallest, so that the backup can be performed in the shortest time.

In the above description, the configuration in which the data transfer device 4 and the tape device 3 are connected to the backup server 2 has been described as an example. However, the data transfer device 4 may be operated as the backup server 2. A similar effect can be obtained. Further, the case where two types of networks, that is, the normal network 6 and the large-capacity / high-speed network 7 are used has been described as an example, but either one of the networks may be used.

[0036]

As described above, according to the present invention, the backup data generated from the original data stored in the storage device is received via the first network, sequentially stored, and the received backup data is stored. Based on the data, the original data in the storage device is reconstructed and stored as reconstructed data, so that, as before, the tape at the time of the last full backup and the tape backed up thereafter are appropriately combined. Since there is no need to recover data, the work load required for data recovery can be greatly reduced.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a data backup system according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing an operation when an incremental backup is used.

FIG. 3 is an explanatory diagram showing an operation when a differential backup is used.

FIG. 4 is a block diagram showing a conventional data backup system.

FIG. 5 is an explanatory diagram showing an incremental backup method.

FIG. 6 is an explanatory diagram showing a differential backup method.

FIG. 7 is an explanatory diagram showing data recovery by an incremental backup method.

FIG. 8 is an explanatory diagram showing data recovery by a differential backup method.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Information processing device (storage device), 2 ... Backup server, 3 ... Tape device (external data storage means), 4 ... Data transfer device (reconstruction data storage means / data transfer means), 5 ... Data transfer device (data) Transfer means), 6 network (first network), 7 network (second network), 11 to 14 tapes.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Tetsuro Mikazuki 3-19-2 Nishishinjuku, Shinjuku-ku, Tokyo Nippon Telegraph and Telephone Corporation

Claims (8)

[Claims] 1. A data backup system for backing up original data stored in a storage device via a network, wherein the data backup system is connected to the storage device via a first network, and the original data stored in the storage device is A backup server that receives the generated backup data via the first network; an external data storage unit that is connected to the backup server and sequentially stores the backup data received by the backup server; A data backup system comprising: reconstructed data storage means for storing original data reconstructed based on backup data received by a server as reconstructed data. 2. The data backup system according to claim 1, wherein the reconstructed data stored in the reconstructed data storage means is transferred to a storage device via a first network or a different second network. A data backup system comprising data transfer means for restoring original data in a storage device. 3. The data backup system according to claim 1, wherein the backup data consists of only files that have been changed from the previous backup point in the original data in the storage device. system. 4. The data backup system according to claim 1, wherein the backup data includes all files changed from a reference backup time. 5. A data backup method for backing up original data stored in a storage device via a network, wherein the backup data generated from the original data stored in the storage device is transferred via a first network. A data backup method comprising: receiving and sequentially storing data; and reconstructing original data in a storage device based on the received backup data and storing the reconstructed data. 6. The data backup method according to claim 5, wherein the reconstructed data is transferred to the storage device via the first network or a different second network.
A data backup method for restoring original data in a storage device. 7. The data backup method according to claim 5, wherein, of the original data in the storage device, only files that have been changed since the previous backup are backed up as backup data. Method. 8. The data backup method according to claim 5, wherein all files changed from a reference backup time are backed up as backup data.