JPH0683498A - File protection system - Google Patents

Abstract

PURPOSE:To protect file contents by guaranteeing normal access to a file storage means stored with a system file even if a telephone exchange is powered OFF or has a drop in power source voltage. CONSTITUTION:A DET 2 once detecting the power source break or power source voltage drop of a POW 1 informs a DKC 3 of the abnormal state. In response to the information, the DKC 3 interrupts access to a DKE 4 at the moment when sector access ends if a DKE 4 is currently accessed. When the DKE 4 is not currently accessed, no processing is performed even if power source abnormality information is received.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a file protection system, and more particularly to a file protection system for protecting files such as programs, station data and subscriber data stored in a magnetic disk unit in a telephone exchange when a power failure occurs.

[0002]

2. Description of the Related Art In a conventional telephone exchange, a non-interruptible power supply unit is connected to the outside to prevent power failure.
There is no specific file protection measure in case of power failure such as voltage drop.

[0003]

This conventional telephone exchange does not take into consideration the failure of the non-interruptible power supply connected to the outside, and takes special file protection measures when an abnormality such as a voltage drop occurs. If the power supply becomes unstable while the magnetic disk is being accessed, especially while the disk is being written, the contents of the disk may be destroyed. As a result, system files such as programs and station data may be destroyed, resulting in a system down. In many cases, there was a big problem that the reliability of the telephone exchange itself was significantly reduced.

Further, when the power failure is recovered, a recovery process such as loading a system file from the magnetic tape device to the magnetic disk is required, and the service cannot be provided for a long time, which causes a trouble to the user. there were.

[0005]

According to the file protection method of the present invention, a file storage means for storing a file including a program, station data and subscriber data, a control means for controlling access to the file storage means, and a power supply abnormality. And a backup power supply for supplying power to the file storage means when the power supply is abnormal, and when the detection means detects the power supply abnormality, the control means is notified of this and the control means If the file storage means is being accessed when the notification is received, the processing is interrupted at the end of sector access.

The file storage means is a magnetic disk device, the control means is a magnetic disk controller, and the backup power source is a battery.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of a file protection system of the present invention, showing only file-related blocks.

The telephone exchange of the present embodiment comprises a magnetic disk unit (hereinafter referred to as DKE) 4 for storing files including programs, office data and subscriber data, a magnetic disk controller (hereinafter referred to as DKC) 3 for controlling access to DKE 4, and a system. Power supply (hereinafter referred to as POW) 1 that supplies the necessary voltage (+ 5V, etc.), a detection unit (hereinafter referred to as DET) 2 that detects POW1 abnormality, a backup power supply (hereinafter referred to as BAT) 5 for DKC3 and DKE4, DKC3 and data Bus (hereinafter D
B) 8, a central processing unit (hereinafter, CPU) 6 connected via an address bus (hereinafter, AB) 6, a main storage device (hereinafter, M)
M) 7 is included.

Next, the operation of this embodiment will be described.
When the DET 2 detects a power supply abnormality such as a decrease in the supply voltage from the POW 1, the DKC 3 is notified of the abnormal state. DKC3
By receiving this notification, if DKE4 is currently being accessed, DKE will be
Suspend access to 4. Further, if DKE4 is not being accessed, no particular processing is performed. In this way, the DKC3 suspends the access to the DKE4 when the POW1 output is unstable, and protects the contents of the DKE4.

This processing is generally executed by reading the program from the MM7. Even when the input power source of POW1 is abnormal, power is supplied from BAT5 to DKC3 and DKE4, and the above program is executed.

[0011]

As described above, according to the present invention, if the file storage means is being accessed at the time of detecting an abnormality in the power supply to the telephone exchange, the control means performs the subsequent processing at the end of the series of processing operations. Since the interruption is performed, there is an effect that the contents of the file can be protected without accessing the file when the power supply is unstable.

Further, since the file access interruption process is generally executed by software, it has an economical effect.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a file protection system of the present invention.

[Explanation of symbols]

 1 power supply (POW) 2 detection unit (DET) 3 magnetic disk controller (DKC) 4 magnetic disk device (DKE) 5 backup power supply (BAT) 6 central processing unit (CPU) 7 main storage device (MM) 8 data bus (DB) ) 9 Address bus (AB)

Claims (2)

[Claims] 1. A file storage means for storing a file containing a program, station data and subscriber data, a control means for controlling access to the file storage means, a detection means for detecting a power supply abnormality, and a means for detecting a power supply abnormality. A backup power supply for supplying power to the file storage means,
When the detection means detects the power supply abnormality, the control means is notified of this, and the control means interrupts the process at the end of sector access if the file storage means is being accessed when receiving the notification. Characteristic file protection method. 2. The file protection system according to claim 1, wherein the file storage means is a magnetic disk device, the control means is a magnetic disk controller, and the backup power source is a battery.