JPS6363173A - Duplex disk control system - Google Patents

Abstract

PURPOSE:To shorten a time for restoration when trouble is occurred in a disk device during writing information and impossible to report to a central processing unit, by communicating control information to what extent of writing is executed between disk controlling devices and reporting it to the central processing unit. CONSTITUTION:When trouble occurred in a disk device 4 during writing information, and a disk controller 10 is made impossible to report to a central processing unit 1, the central processing unit 1 changes the connection to a channel device 2'. A disk controller 10' makes communication with the disk controller 10 through communicating means 14' and 14, and receives control information to what extent the writing is executed, and reports it to the central processing unit 1 through the channel unit 2'. The central processing unit 1 does not perform the rewriting of information for areas written normally in the disk devices 4 and 4', and makes only the writing of areas in which writing is not terminated normally.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a 21 disk control system for controlling a duplex disk device.

[Conventional technology]

The conventional disk control force type of this type was published in 1986-532.
It is described in Publication No. 9. FIG. 2 is a block diagram showing this conventional duplex disk control system.

In FIG. 2, duplicated disk devices 4 and 4'
are disk controllers 3 and 3', respectively.

It is connected to the central processing unit 1 via channel devices 2 and 2'.

When both channel devices 2 and 2' are normal, disk units f4 and 4' are connected to channel device 2 via disk control device 3, and central processing unit 1 connects channel device 2 and disk Information is written to the disk device 4 via the control device 3, and then an attempt is made to write the same information to the same area of the disk device 4' via the channel device 2 and the disk control device 3. In this case, the channel device 2
If a failure occurs after completing writing of information to the disk device 4, and it becomes impossible to write information to the disk device 4',
[Central processing unit that received a fault report from channel device 2 from channel device 2] Although information was written to disk device 4, information was not written to both disk drives R4 and 4'. It is determined that the Thereafter, the central processing unit 1 transfers the normal disk devices 4 and 4' to the channel device 2.
', disconnect the failed channel device 2, write the information to the disk device 4 again via the channel device 2' and the disk controller 3', and write the same information to the disk device 4'. I was supposed to write information.

[Problem that the invention seeks to solve]

The above-mentioned conventional duplex disk control force method is effective even when information is not written only to the disk device 4' due to a failure in one channel device (for example, 2), the central processing unit
determines that no information has been written to the two disk devices 4 and 4', and the disk is not written even though tji fi has been written to the one disk device 4 via the other channel device 2'. The disadvantage is that the same information must be written into the device 4 again.

(Means for Solving Problem 1'L1) The duplex disk control system of the present invention includes a central processing unit, a duplex disk device, and a pair of disk control devices mutually connected to the duplex disk device. and a communication means for communicating between the disk control devices, and when the disk control device of the sword detects an abnormality in writing information to the disk device and cannot report it to the central processing unit, the The external disk control device communicates how far it has written using the communication means and reports it to the central processing unit, so that the central processing unit rewrites the normally written area of the duplexed disk device. Embodiment 0 Next, the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of one embodiment of the present invention. Duplicated disk devices 4 and 4' each have a disk control device [
10 and 10' and the central processing unit via channel devices 2 and 2'.

The disk controllers 10 and 10' include interface means 1 and 11', operation control means 12 and 12',
Disk control means 13 and 13' and communication means for mutually communicating control information about how much has been written] 4 and 14'
It consists of The central processing unit 1 has a channel device 2,
Information is written to the disk device 4 via the disk control device 10ft, and the information is written to the disk device 4 via the disk control device 10ft.
An attempt is made to write the same information to the disk device 4' via '. In such a case, if a failure occurs while writing information to the disk device 14 and the disk control device 10 is unable to report to the central processing unit 14, the central processing unit 4'
When the writing is completed, the connection is changed to the channel device 2' to disconnect the faulty channel device f2, and the disk controller 10 is connected to the disk controller a10' via the channel device 2'. Issues an instruction to read control information about how much has been written. The disk control device 10' communicates with the disk control device 0 through the communication means 14' and 14G, and receives control information indicating how much data has been written.
When receiving control information indicating whether the data has been written to the central processing unit 1 via the channel device 2', the central processing EJ device 1 reports to the central processing unit 1 the data written to the normally written area in the disk devices 4 and 4'. Information is not rewritten, but only the area where writing has not been completed normally is written.

〔Effect of the invention〕

As explained above, when a failure occurs while writing information to a disk device and cannot be reported to the central processing unit, the present invention communicates control information about how much 1 has been written between disk control devices, and the central processing By reporting to the device, the central processing unit does not re-write areas that have been written normally to the disk device, but only writes to areas where writing has not completed normally, reducing recovery time. There is an effect that can be done0

[Brief explanation of drawings]

FIG. 1 is a diagram showing an embodiment of the present invention, and FIG. 2 is a diagram showing a conventional duplex disk system. 1...Central processing unit, 2.2'...Channel device, 4.4'...Disk device, 10.
10'...Disk side control device, 11.11'.
...interface means, 12.12'...
...Operation control means, 13.13'...Disc control means, 14.14' fTM

Claims (1)

[Claims] first and second disk devices connected to a central processing unit; first and second disk control devices respectively connected between the first and second disk devices and the central processing unit; and the disk a communication means for communicating between a control device and the central processing unit, and when an abnormality in writing of information to the disk device by the first disk control device is detected, the second disk control device By reporting the data area written by the first disk control device to the central processing unit, the central processing unit can write data without rewriting the area that has been normally written to the disk device. A dual disk control method characterized by writing only to areas that have not yet been completed.