JPH04268621A - Magnetic disk interface system - Google Patents

Abstract

PURPOSE:To release the occupied state of a controller without turning off its power source by deciding whether the response signal from the controller for an operation confirmation signal can be received within a certain time or not. CONSTITUTION:When a controller 1 or 3 occupies a magnetic disk device 5, a state confirming circuit 7 periodically transmits the confirmation signal for confirmation of the operation of the controller 1 or 3. The controller 1 or 3 receives this signal by a response circuit 2 or 4. The controller 1 or 3 transmits the response signal to a state control circuit 6 of the magnetic disk device 5. When the response signal is received within a certain time after transmission of the confirmation signal, the state control circuit 6 keeps the occupied state due to the controller 1 or 3 as it is. If the response signal cannot be received, the control circuit 6 releases the occupied state of the magnetic state 5 due to the controller 1 or 3. Thus, the magnetic disk device can be accessed by another controller (omitted in the figure).

Description

[Detailed description of the invention]

0001

[Field of Industrial Application] The present invention relates to a magnetic disk interface system, and in particular, even if a cross-call-connected magnetic disk device stops operating while being occupied by one controller, the magnetic disk device itself can determine the occupied status. This invention relates to a magnetic disk interface method that can release the data.

0002

[Prior Art] Conventional interface methods for magnetic disks that are cross-call connected to multiple controllers are as follows:
When a controller occupying a magnetic disk device stops operating, the magnetic disk device remains occupied by that controller, making it impossible for other controllers to access the magnetic disk device. At this time, when it is necessary to enable access from other controllers, this is done by turning off the power of the stopped controller.

0003

[Problems to be Solved by the Invention] In the conventional magnetic disk interface method described above, when the operation of a controller that occupies a magnetic disk device stops, the magnetic disk device remains occupied by that controller. This has the disadvantage that it cannot be accessed from other controllers.

[0004] An object of the present invention is to enable the magnetic disk drive to release the occupied state by the stopped controller, even if one controller stops operating while occupying the magnetic disk drive, without turning off the power to that controller. ,
The object of the present invention is to provide a magnetic disk interface method that allows access from other controllers.

[0005]

[Means for Solving the Problems] A magnetic disk interface system according to a first aspect of the invention is a magnetic disk system comprising a magnetic disk device and a plurality of controllers, the magnetic disk device and the controllers being cross-call connected. (A) While the magnetic disk device is occupied by a first controller that is one of the plurality of controllers, the magnetic disk device periodically performs the following on the first controller: a status confirmation means for transmitting a confirmation signal for confirming the operation of the first controller and outputting a confirmation signal transmission notification indicating that the confirmation signal has been transmitted; (B) a confirmation output by the status confirmation means; When receiving a signal transmission notification and receiving a response signal from the controller in response to the confirmation signal within a predetermined period of time, the occupied state by the first controller is maintained as it is, and the controller responds to the confirmation signal. (C) state control means for releasing the occupied state of the magnetic disk device by the first controller when there is no response signal from the first controller;
response means for immediately transmitting the response signal to the state control means when receiving the confirmation signal transmitted from the state confirmation means when the magnetic disk device is occupied as a controller of There is.

[0006] A magnetic disk interface system according to a second aspect of the present invention is a magnetic disk system including a magnetic disk device and a plurality of controllers, and in which the magnetic disk device and the controllers are cross-call connected. is occupied by a first controller that is one of the plurality of controllers, a confirmation signal periodically sent to the first controller to confirm the operation of the first controller; After receiving the confirmation signal sent from the magnetic disk device, the first controller immediately sends a response signal to the magnetic disk device, and the magnetic disk device When a response signal from the first controller to the confirmation signal is received within a certain period of time, the occupied state by the first controller is maintained as it is, and a response signal from the controller to the confirmation signal is received within a certain period of time. If there is no magnetic disk device, the first controller is configured to release the magnetic disk device from occupation.

[0007]

Embodiments Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of the magnetic disk interface system of the present invention.

The magnetic disk interface system of this embodiment is composed of a magnetic disk device 5 and controllers 1 and 3, as shown in FIG.

Further, while the magnetic disk device 5 is occupied by the controller 1 or the controller 3, the magnetic disk device 5 periodically sends the following information to the controller.
A status confirmation means 7 that transmits a confirmation signal to confirm the operation of the controller and outputs a confirmation signal transmission notification indicating that the confirmation signal has been transmitted, receives a confirmation signal transmission notification outputted by the status confirmation means 7, When a response signal from the controller to the confirmation signal is received within a predetermined period of time, the occupied state by the controller is maintained as it is, and when there is no response signal from the controller to the confirmation signal, the magnetic disk is removed by the controller. It is comprised of a state control means 6 for releasing the occupied state of the device 5.

Furthermore, when the controllers 1 and 3 occupy the magnetic disk device 5 and receive the confirmation signal transmitted from the status confirmation unit 7, the controllers 1 and 3 have response means for immediately transmitting a response signal to the status control unit 6. It is composed of 2 and 4.

Next, the operation will be explained.

In FIG. 1, the state control circuit 6 in the magnetic disk drive 5 is in one of three states: occupied by the controller 1, occupied by the controller 3, and not occupied by either controller. The connection between the magnetic disk device 5 and the controllers 1 and 3 is controlled so that the state is maintained.

The controllers 1 and 3 can access the magnetic disk device 5 only when the magnetic disk device 5 is occupied, and the magnetic disk device 5 occupied by one controller cannot be accessed from the other controller. It will be ignored.

In FIG. 1, for example, when the controller 1 occupies the magnetic disk drive 5, the status control circuit 6 notifies the status confirmation circuit 7 through the status communication line 16 that the magnetic disk drive 5 is occupied by the controller 1. Upon receiving this communication, the status confirmation circuit 7 periodically sends a message to the response circuit 2 of the controller 1 through the confirmation line 12.
At the same time as transmitting the status confirmation signal, a confirmation signal transmission notification is output to the status control circuit 6 through the confirmation line 15 to notify the controller 1 that the status confirmation signal has been transmitted.

On the other hand, in response to the status confirmation signal from the status confirmation circuit 7 received by the response circuit 2, the controller 1 performs status control via the response line 11 within a certain period of time if the controller 1 itself is operating normally. A response signal is sent to circuit 6. If the state control circuit 6 receives a response signal from the controller 1 within a certain period of time after receiving the contact signal from the state confirmation circuit 7, it continues to maintain the occupied state by the controller 1.

However, while occupying the magnetic disk drive 5,
If the controller 1 itself does not operate normally, no response signal is sent to the status control circuit 6 through the response line 11, so the status control circuit 6 waits for a certain period of time after receiving the communication signal from the status confirmation circuit 7. Controller 1 is no longer able to receive a response signal within
It is determined that the operation of the controller 1 is not normal, and the state of occupation by the controller 1 is released. When the occupied state by the controller 1 is released, the magnetic disk device 5
Since the controller 3 is not occupied by any of the controllers 3, the controller 3 can perform an exclusive operation again, and the controller 3 can access the controller 3.

In the above explanation, the case where the controller 1 first occupies the magnetic disk device 5 has been explained, but even if the controller 3 first occupies the magnetic disk device 5, the same operation as above is performed. .

[0019]

As explained above, in the magnetic disk interface system of the present invention, when a magnetic disk device is occupied by a controller, the magnetic disk device sends a confirmation signal to the controller to confirm the operation of the controller. It is determined whether the controller is operating normally or not by periodically transmitting a confirmation signal and determining whether a response signal from the controller can be received within a predetermined period of time. , if one controller stops operating while occupying a magnetic disk unit, the magnetic disk unit will release the occupied status by the stopped controller and will not be able to accept requests from the other controller, without having to turn off the power to that controller. This has the effect of making access possible.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of a magnetic disk interface system of the present invention.

[Explanation of symbols]

1 Controller 2 Response circuit 3 Controller 4 Response circuit 5 Magnetic disk device 6 Status control circuit 7 Status confirmation circuit 11 Response line 12 Confirmation line 13 Response line 14 Confirmation line 15 Confirmation line 16 Status contact line

Claims (2)

[Claims] 1. A magnetic disk system comprising a magnetic disk device and a plurality of controllers, wherein the magnetic disk device and the controllers are cross-call connected, wherein the magnetic disk device (A) is connected to the plurality of controllers. While the magnetic disk device is occupied by a first controller that is one of the controllers, a confirmation signal is periodically sent to the first controller to confirm the operation of the first controller. (B) within a predetermined period of time upon receiving the confirmation signal transmission notification output by the status confirmation means; When a response signal from the controller to the confirmation signal is received, the state of occupation by the first controller is maintained as it is, and when there is no response signal from the controller to the confirmation signal, the state of occupation by the first controller is maintained. state control means for releasing the occupied state of the magnetic disk device, and when each of the plurality of controllers (C) occupies the magnetic disk device as the first controller,
A magnetic disk interface system characterized by comprising: response means for immediately transmitting the response signal to the state control means when receiving the confirmation signal transmitted from the state confirmation means. 2. A magnetic disk system comprising a magnetic disk device and a plurality of controllers, the magnetic disk device and the controllers being cross-call connected, wherein the magnetic disk device is one of the plurality of controllers. 1, periodically sends a confirmation signal to the first controller to confirm the operation of the first controller, and the first controller immediately transmits a response signal to the magnetic disk device after receiving the confirmation signal transmitted from the magnetic disk device, and the magnetic disk device responds to the confirmation signal in response to the confirmation signal within a predetermined period of time. When a response signal from the first controller is received, the occupation state by the first controller is maintained as it is, and when there is no response signal from the controller to the confirmation signal within a certain period of time, the first controller A magnetic disk interface method characterized by releasing a magnetic disk device from being occupied by a controller.