JPH0566895A - Electric disk subsystem - Google Patents

Abstract

PURPOSE:To obtain a highly reliable electronic disk subsystem which permits data saving during operation without stopping the electronic disk device or degrading its performance. CONSTITUTION:Electronic disk processing devices 1 and 2 are so controlled by a host device as to make connection with electronic disk devices 3, 4, 5 and 6 which include semiconductor memories, that is storage media, and to control them. Further, electronic disk devices 3 and 4 are so constituted as to permit dual writing and both are connected with each other through a dual writing copy interface 8. An auxiliary storage device 7 is cross-call connected with the electronic disk devices 3 and 4 and start-up can be executed from any side. Within the electronic disk devices 3, 4, 5 and 6, a diagnosis and maintenance control part which controls a dual writing copy interface which transfers data to and from the electronic disk device constituting a pair with dual writing, and controls a SVD interface which transfers data to and from an auxiliary storage device 7 and also performs internal diagnosis and maintenance.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic disk subsystem, and more particularly to an electronic disk subsystem having a function of saving data in operation.

[0002]

2. Description of the Related Art In a conventional electronic disk subsystem,
The data stored in the electronic disk device (hereinafter referred to as EDU) is saved in the auxiliary storage device (hereinafter referred to as SVD) only when the power is automatically turned off. Is to prevent the data on the electronic disk device from being lost due to the deterioration of the battery capacity.

In the above-mentioned conventional electronic disk subsystem, the data stored in the EDU is saved in the SVD only automatically when the power is turned off, so that the data is continuously stored for 24 hours. There is a problem that the data cannot be saved to the SVD when operating. To save data during operation, save it to a magnetic tape or disk in the host device, or if you want to save the data to the SVD, execute it after turning off the EDU power once. There is no other way than doing this. In this case, during the save operation,
The corresponding EDU will be blocked or unusable for a long time, resulting in a waste of time. Therefore, in order to improve reliability, in a system that requires frequent backup, the electronic disk sub There is a problem that the system performance cannot be fully exhibited.

It is an object of the present invention to provide a highly reliable electronic disk subsystem capable of saving data during operation without stopping the EDU or degrading the performance.

[0004]

An electronic disk subsystem according to the present invention includes two electronic disk devices each having a dual writing mechanism which uses a semiconductor memory as a storage means and writes the same data into each of them. And an electronic disk processing device for controlling an electronic disk device having a dual writing structure.
Has an auxiliary storage device that is cross-call connected so that it can be accessed from either of the electronic disk devices.
In the electronic disk subsystem in which one of the two electronic disk devices is registered in advance as a primary electronic disk device to be mainly used and the other is registered and used as a secondary electronic disk device to be used as a spare during system operation, When a data save command is received from the electronic disk processing device in one electronic disk device, the electronic disk device registered as the primary electronic disk device ignores the save command and registers it as the sub electronic disk device. The electronic disk device is provided with a diagnostic maintenance control unit having a function of saving and storing data in the auxiliary storage device.

In the electronic disk subsystem of the present invention, after the diagnostic maintenance control unit of the secondary electronic disk device saves the data in the auxiliary storage device and finishes the storage, the data is taken from the primary electronic disk device and restored to the dual writing structure. It may have a function to do.

[0006]

Embodiments of the present invention will now be described with reference to the drawings.

FIG. 1 is a block diagram of an embodiment of the present invention.

Electronic disk processing devices (hereinafter referred to as EDC) 1 and 2 are controlled by a host device (not shown) and include EDUs 3, 4 including a semiconductor memory as a storage medium.
Connect to 5 and 6 to control each. Also, EDU3
Reference numeral 4 has a double-writing configuration, which are mutually connected by a double-writing copy interface 8. SVD7 is EDU
It is cross-call connected to 3 and 4, and can be activated from any of the EDUs 3 and 4.

FIG. 2 is a block diagram of the electronic disk device.

In the EDU 20, a port control unit 21 that controls the interface with the EDC exchanges data with a memory control unit 23 that controls the semiconductor memory 24 that holds the data and an EDU that forms a pair of duplicated data. The configuration is such that it is connected to the diagnostic maintenance control unit 22 for performing internal diagnostics and maintenance, which has the control function of the SVD interface 26 for controlling the double-copy interface 25 for performing the above and for transmitting and receiving data with the SVD.

Next, the operation will be described. Figure 1 for explanation
Is mainly used, and FIG. 2 is used supplementarily.

When the host device instructs the EDC1 to save the data of the dual-duplex EDU3, 4 to the SVD7, the EDC1 operates the dual-duplex EDU3, 4 in operation.
Issue a save command to Double-edged EDU3,4
For example, when the EDU 3 is a primary electronic disk device and the EDU 4 is a secondary electronic disk device, when the save command is received, the EDU 4 becomes offline by the operation of the diagnostic maintenance control unit 22 and the current data is used by the SVD interface 26. And save to SVD7. When the evacuation of the EDU4 is completed, the diagnosis / maintenance control unit 22 of the EDU4
Communication is performed with the diagnostic maintenance control unit 22 of the DU3, and the data of the EDU3 is copied to the semiconductor memory 24 of the own device by using the dual writing copy interface 8 and restored.

On the other hand, the EDU 3 is in the process of being saved in the SVD 7 by the EDU 4 and being copied for restoration as a double writing.
Since it is operated as a single writing, access from the host device can be continuously performed even during the saving period and during copying.

[0014]

As described above, according to the present invention, the electronic disk device registered in the two electronic disk devices as a primary electronic disk device when a data save command is received from the electronic disk processing device is used. An electronic disk device registered as a secondary electronic disk device, ignoring save commands, has a diagnostic maintenance control unit that has the function of saving and storing data in an auxiliary storage device, thereby stopping the electronic disk device and improving performance. There is an effect that the data can be saved during the operation without lowering or sacrificing the reliability.

[Brief description of drawings]

FIG. 1 is a block diagram of an embodiment of the present invention.

FIG. 2 is a block diagram of an electronic disk device.

[Explanation of symbols]

 1, 2 Electronic Disk Processing Device (EDC) 3, 4, 5, 6, 20 Electronic Disk Device (EDU) 7 Auxiliary Storage Device (SVD) 8, 25 Duplex Copy Interface 21 Port Control Unit 22 Diagnostic Maintenance Control Unit 23 Memory control unit 24 Semiconductor memory 26 SVD interface

Claims (2)

[Claims] 1. Control of two electronic disk devices provided with a dual writing mechanism for writing the same data into each of them using a semiconductor memory as a storage means, and control of the two electronic writing devices having a dual writing structure. The electronic disk processing device and the above 2
Has an auxiliary storage device that is cross-call connected so that it can be accessed from either of the two electronic disk devices,
In the electronic disk subsystem, one of the two electronic disk devices is registered in advance as a primary electronic disk device to be mainly used during system operation, and the other is registered and used as a secondary electronic disk device for preliminary use. When a data save command is received from the electronic disk processing device in one electronic disk device, the electronic disk device registered as the primary electronic disk device ignores the save command and registers it as the sub electronic disk device. An electronic disk subsystem, wherein the electronic disk device is provided with a diagnostic maintenance control unit having a function of saving and storing data in the auxiliary storage device. 2. The diagnostic maintenance control unit of the secondary electronic disk device has a function of retrieving data from the primary electronic disk device after restoring the data to the auxiliary storage device and terminating the storage to restore the dual writing configuration. The electronic disk subsystem according to claim 1.