JP2000200453A - Medium controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to exactly recognize the error which occurs during the medium loading/unloading processing to be executed by changing an accessor control section and a drive control section by connecting both control sections and imparting negotiation thereto. SOLUTION: This medium controller has an accessor means which internally holds plural information recording media and transports the arbitrary medium among the plural information recording media described above, the accessor control section which controls the operation of the accessor means, the drive means which subjects the medium transported by the accessor means to read/ write processing and the drive control section which controls the operation of the drive means. The host device 5 is the medium controller which is selectively connected to the accessor control section and the drive control section and with which the medium control is executed. In such a case, the medium controller is constitute in such a manner that the information exchange with each other is made possible by connecting the accessor control section and the drive control section.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a medium control device, and more particularly to a medium control device such as a library or an autoloader used as a peripheral device in a computer system for controlling an information recording medium.

[0002]

2. Description of the Related Art A medium control device such as a magnetic tape library transports a corresponding medium from a magazine (medium storage location) to a drive as a processing operation when a read / write command for a specific medium is received from a host device. And a second step of loading a medium into a drive and setting the medium in a read / write enabled state (hereinafter referred to as a READY state). When ending the read / write operation to the medium, the first and second steps are performed in reverse to store the medium in the magazine. In a conventional medium control device, an accessor control unit of the device negotiates with a host device in a first process (medium transport process), and a drive control unit of the device negotiates with a host device in a second process (medium loading process). And these negotiations are conducted separately and independently.

On the other hand, a drive used in such a medium control device is configured by directly incorporating a drive used alone as it is into the device. The operator manually loads the recording medium into the single drive itself,
The medium unloaded from the single drive is then transported and stored by the operator. If there is an error during loading of the medium in such a single drive, the normal drive unloads the medium as it is to allow the operator to reprocess (reload the medium). In this case, if the single drive reports a failure when loading media as an error to the higher-level device, the higher-level device takes measures such as restarting the system each time. Without reporting, it is general to merely indicate to the host device that it is still in a read / write disabled state (hereinafter, referred to as a NOTREADY state).

[0004]

As described above, in the conventional medium control device, when the medium is transported by the accessor, the accessor control unit negotiates with the host device such as normal end or abnormal end, and separately loads the medium. Sometimes the drive control unit is ready or not
Negotiation such as READY is performed. Also,
Since the drive constituting the device is a single drive, the drive control unit does not report a failure in loading the medium as an error to the host device. Therefore, there are the following problems.

That is, it is assumed that, for example, when the accessor loads a medium after transporting the medium, the medium is inserted into the drive in a shifted state. Since there is no error in the medium transport by the accessor, the accessor control unit reports the normal end to the upper-level device, and upon receiving this, the upper-level device switches the negotiation destination to the drive control unit, and the drive returns to NO.
Wait until the state changes from TREADY to READY. However, the drive ejects the medium in order to prompt the user to insert it again (essentially, the operator) and continues to return NOTREADY without reporting an error to the host device. Even in this case, the host device is ready
, The interruption of the job is prolonged, causing an accident such as a system down. Or,
If there is no error report from the drive, the higher-level device attempts to execute the next process, which may cause an unexpected error.

When the next process is performed without the upper device recognizing the error, an error will be reported to the higher device in a later process. Is mistakenly recognized as an error in the process, and as a result, an erroneous error treatment is performed.

Further, the medium control device generally has a retry function of the medium control operation. However, if the error report is incorrect as described above, the retry function of the medium control device cannot be effectively performed. Alternatively, the retry function may malfunction and cause a further trouble.

Accordingly, the present invention provides a medium control device which is used in a backup operation of a computer system and which realizes automation or unmanned operation. It is an object of the present invention to provide a medium control device that can accurately recognize an error and take an appropriate countermeasure.

[0009]

In order to achieve this object, a medium control device according to the present invention holds a plurality of information recording media therein and conveys any one of the plurality of information recording media. Accessor means, an accessor control unit for controlling the operation of the accessor means, a drive means for performing read / write processing on a medium conveyed by the accessor means, and a drive control unit for controlling the operation of the drive means A medium control device in which a host device is separately connected to the accessor control unit and the drive control unit to perform medium control, wherein the accessor control unit and the drive control unit are connected, The feature is that information can be exchanged.

As described above, by connecting the accessor control unit and the drive control unit of the medium control device and having mutual negotiation, even if there is an error during loading of the medium as described above, for example, Can be accurately detected and appropriate action can be taken.
In addition, it is possible to prevent inconvenience due to erroneous recognition of an error.

In the medium control device according to the present invention, the accessor control section determines whether the medium is normally stored in the drive means when the accessor means has normally conveyed the medium. It is desirable to inquire of the drive control unit about the above.

Further, in the medium control apparatus according to the present invention, the accessor control unit may control the accessor unit to execute the medium control if the medium is not normally stored in the drive unit as a result of an inquiry to the drive control unit. And confirming whether the accessor means holds the medium and controlling the accessor means to attempt to reinsert the medium when the accessor means holds the medium.

Further, the medium control device of the present invention is characterized in that the accessor control section stores the medium in the host device even if the reinsertion processing is not normally completed after the medium reinsertion processing by the accessor means. The normal termination of the process is reported.

In the medium control apparatus according to the present invention, the medium can be read / written by the drive control unit when the host device receives a report from the accessor control unit that the medium storage processing has been normally completed. It is characterized by inquiring whether or not it is in a state.

As described above, according to the medium control device of the present invention, the accessor control unit monitors up to the medium loading process by the drive means which has not been monitored conventionally.
Even a medium control device using a single drive that does not report an error at the time of loading a medium to a higher-level device can accurately grasp the presence of an error in a medium loading process.
Also, when an error occurs during loading of the medium, the accessor control unit checks whether the accessor means holds the medium, that is, whether the medium has been ejected from the drive means,
If it has been ejected, the accessor means can execute a load retry to continue the processing. Furthermore,
If recovery is not possible even after this retry, accurate error information is reported to the higher-level device, so that the higher-level device and the operator can perform appropriate maintenance processing. Therefore, it is possible to accurately recognize an error that occurs during the process of transporting the medium from the magazine to the drive and changing the drive to the READY state, and to take appropriate measures.

Further, the medium control device according to the present invention, when the higher-level device issues an instruction to eject the medium from the drive unit to the drive control unit, before the drive unit ejects the medium, An accessor control unit controls the accessor means to be positioned in front of a medium outlet of the drive means.

Further, the drive control section controls the medium to be ejected from the drive means even if the control for positioning the accessor means does not end normally. The drive control unit reports the fact to a host device.

If the apparatus is configured to control the operation at the time of unloading the medium, the accessor means can be positioned before the medium outlet of the drive before the unloading operation of the medium, and an accurate error can be transmitted to the host apparatus. Since reporting is possible, the probability of occurrence of an unexpected failure can be reduced even during unload processing.

Further, the medium control device of the present invention uses the SCS for information exchange between the accessor control unit and the drive control unit.
It is desirable to use the I (Small Computer System Interface) protocol. As described above, the device of the present invention improves the accuracy of error detection by performing simple negotiation between the accessor control unit and the drive control unit, and takes appropriate preventive measures. If the standardized SCSI protocol is applied and used for the negotiation, the object of the present invention can be easily achieved with a simple configuration.

[0020]

Embodiments of the present invention will be described below with reference to the accompanying drawings. 1 and 2 are diagrams showing the operation of the medium control device of the present invention. Before describing the operation of the apparatus with reference to these drawings, the configuration of the medium control apparatus will be briefly described. The medium control device is an information recording unit used for backup operation of a computer system and the like, and executes a read / write process on a magazine for storing a plurality of information recording media such as a magnetic tape medium and any of the media. And one or more drives to perform the read / write process on the designated medium in response to a command from a higher-level device. . Basically, the operation of the accessor is controlled by the accessor control unit, and the operation of the drive is controlled by the drive control unit.

When this medium control receives a read / write command for a specific medium from the host device, the accessor control section drives the accessor to take out the specified medium from the magazine and transport it to the drive. Upon arriving at the drive, the accessor loads the media into the drive by pushing the media into the media insertion / ejection opening of the drive. Thereafter, under the control of the drive control unit, the drive performs read / write processing on the medium. At the end of the read / write processing, the drive unloads the medium under the control of the drive control unit that has received the unload command from the host device, and the medium ejected from the medium insertion / ejection port is transported again by the accessor, and the magazine Is returned to. Since these operations and controls are not different from those of a known medium control device, detailed illustrations thereof are omitted.

Referring to FIG. 1, the operation of the medium control device for loading a medium will be described in detail. An area 1-1 shown in FIG. 1 indicates a control operation of the accessor control unit,
The area 1-2 indicates the control operation of the drive control unit. For convenience of clearly indicating the command transmission destination of the host device, the host device 5 will be illustrated and described on both the accessor control unit side and the drive control unit side. In the loading process in the medium control device, first, the host device 5 issues a medium transport instruction (Order 1) specifying the magazine and drive addresses to the accessor control unit. The accessor control unit drives the accessor (Order 2), and moves the medium from the magazine at the specified address to the drive at the specified address (Process 1). If an error occurs in the transport operation processing (Error 3), the accessor control unit reports an error to the host device (Error 4) and ends the processing. If the transport operation processing ends normally, the accessor control unit returns to the host. Inquires about the status of the drive to the drive control unit without reporting to the drive controller (Good 5) (Order 6). Here, when an error (Error 4) is reported to the higher-level device, the higher-level device recognizes the error at the time of transporting the medium, and performs processing at the time of failure such as a check condition.

An inquiry from the accessor control unit (Order
5) Upon receiving the information, the drive control unit detects whether the medium is normally stored in the drive (Process 2 from Order 7). If the medium is normally stored in this processing 2 (Good 8), the accessor control unit reports the normal end to the host device (Good 10). Also, as described below, even if the processing 2 is an error, the accessor control unit reports a normal end to the host device.

That is, processing 2 (medium storage state confirmation)
When the status of the drive becomes an error in (Error
9), the accessor control unit inquires of the accessor whether or not the medium is on the accessor side (from order 14 to processing 3). This inquiry is made by confirming whether the medium recognition sensor of the accessor recognizes the medium. If the accessor recognizes the medium in this process,
The accessor control unit requests the accessor to retry the medium loading operation (process 4). Even if the load is normally performed in this process, or if an error occurs, the accessor control unit reports a normal end to the host device 5 (the Good1 described above).
0). Here, even if there is an error, the normal end is reported because the error is an error on the drive side. To do that.
For this reason, in the present invention, the error here is referred to as processing 5 described later.
In this case, a drive error is reported from the drive control unit to the host device.

An end report from the accessor control unit (Good1
The host device 5 that has received 0) normally transmits a command to the drive control unit after that (Order 11), and the drive control unit reads the medium (RE) in the drive (RE).
(ADY state) or not (order 12 to processing 5). If the process is in the READY state, the drive control unit reports the fact to the host device 5 (Good 13).
The loading process is terminated, and if an error occurs, the error is reported to the host device 5 (Error 14). The case where an error has occurred in the above processes 2 to 4 (status confirmation to retry process) is also reported here, and the host device can accurately recognize that the error has occurred on the drive side.

Next, an unloading operation of the medium control device will be described with reference to FIG. In FIG. 2, area 2
-1 shows a control operation of the accessor control unit, and a region 2-2 shows a control operation of the drive control unit. After the medium has been read / written by the drive, the host device 5 usually sends an unload command to the drive control unit (Order 2).
1). At this time, the drive control unit does not immediately cause the drive to execute the unload processing, and reports to the accessor control unit that the unload command has been received (Order 22). Upon receiving this, the accessor control unit controls the accessor to position it in front of the medium insertion / ejection port of the specified drive (process 6). Even if this processing ends normally or an error occurs, the end of processing 6 is reported to the drive control unit (Good or Error 23). Contrary to the above, since this error is an error on the accessor side, it is to prevent an error from being reported to a higher-level device in negotiation with the drive control unit. If the process 6 results in an error, it is detected in a process 8 described later.

The drive control unit which has received the end report of the process 6 controls the drive to unload the medium (Order
24 to processing 7). If the unload processing is performed normally, the drive control unit reports a normal end to the host device (Go
od25), when an unload error occurs, the drive control unit reports the occurrence of the error to the host device (Error2).
6). Upon receiving the error report, the host device recognizes the error as a drive-side error and performs a failure process such as a check condition.

When the higher-level device receives a report of the normal end of the process 7 from the drive control unit, it normally issues a medium storage command designated to the magazine address from the drive address to the accessor control unit (Order 27). The control unit drives the accessor to control the medium in the designated drive to return to the designated magazine (Order 2).
8 to processing 8). If there is no problem with this processing, the accessor control section reports the normal end to the higher-level device (Good 29), and ends the processing. If an error occurs, the accessor controller reports an error to the higher-level device (Error 30). An error in the process 6 is also detected here and reported to the host device as an error on the accessor side. As a result, the higher-level device can correctly recognize the error on the accessor side and perform the processing at the time of failure. Thus, the operation of the medium control device of the present invention ends.

The negotiation between the accessor control unit and the drive control unit in the medium control device is based on a standardized SCSI (Small Computer System).
m Interface) protocol.

[0030]

As described above in detail, according to the medium control device of the present invention, even if the host device is a device that separately connects to the accessor control unit and the drive control unit to perform negotiation, Since the appropriate error information is reported to the device, the host device can accurately obtain the details of the error. As a result, it becomes possible for the higher-level device to perform an appropriate error process on the medium control device and to make an accurate report to the operator. Also, even in a medium control device using a single drive as it is,
It is possible to prevent a subsequent failure due to the fact that a load error is not reported to the host device.

On the other hand, the accessor control unit positions the accessor at an appropriate position at the time of loading and unloading, and the accessor control unit monitors the drive control unit at the time of loading / unloading. Retry processing can be performed, and as a result, the probability of occurrence of an error can be reduced.

Further, even if a single drive is used without modification without modification as described above, an accurate error report and a failure prevention effect can be obtained even if a medium control device is configured.
It is possible to easily and inexpensively configure a medium control device having the above-described effect.

[Brief description of the drawings]

FIG. 1 is a flowchart illustrating an operation of loading a medium in a medium control device according to the present invention.

FIG. 2 is a flowchart showing the operation of the medium control device of the present invention when unloading a medium.

[Explanation of symbols]

 1-1, 2-1 Control operation of accessor control unit 1-2, 2-2 Control operation of drive control unit 5 Host device

Claims (8)

[Claims] 1. An accessor means for holding a plurality of information recording media therein and transporting any of the plurality of information recording media, an accessor control unit for controlling the operation of the accessor means, and the accessor means And a drive control unit for controlling the operation of the drive unit. The host device is separately connected to the accessor control unit and the drive control unit. A medium control device for performing medium control by connecting the accessor control unit and the drive control unit so that information can be exchanged with each other. 2. The medium control device according to claim 1, wherein the accessor control unit determines whether or not the medium is stored in the drive unit normally when the accessor unit ends the conveyance of the medium normally. A media control device for inquiring of the drive control unit about the above. 3. The medium control device according to claim 2, wherein the accessor control unit determines that the accessor unit is not normally stored in the drive unit as a result of an inquiry to the drive control unit. A medium control device that checks whether the medium holds the medium, and controls the accessor to try to reinsert the medium when the accessor holds the medium. 4. The medium control device according to claim 3, wherein after the medium reinsertion processing by the accessor means, even if the reinsertion processing does not end normally, the accessor control unit sends the medium to the host device. A medium control device for reporting a normal end of medium storage processing. 5. The medium control device according to claim 4, wherein when the higher-level device receives a report from the accessor control unit that the medium storage processing has been normally completed, the medium is read by the drive control unit. / A medium control device for inquiring whether or not it is in a writable state. 6. The medium control device according to claim 1, wherein when the higher-level device issues an instruction to eject the medium to the drive control unit, the drive control unit controls the drive unit. A medium control device for issuing a command to the accessor control unit to position the accessor unit in front of the drive unit before discharging the medium. 7. The medium control device according to claim 6, wherein the drive control unit causes the drive unit to eject the medium even when the position control of the accessor unit by the accessor control unit does not end normally. A medium control device characterized by the above-mentioned. 8. The medium control device according to claim 1, wherein a small computer system (SCSI) is used for exchanging information between the accessor control unit and the drive control unit.
m) a media control device characterized by using a protocol.