JPH08212110A - Remote maintenance method for system - Google Patents

Abstract

PURPOSE: To provide the remote maintenance method for system with which the hang-up of a system bus, the restart of a computer system generating a fault such as the runaway of a CPU and maintenance are enabled from an external line to a computer system equipped with a system management mode. CONSTITUTION: At the computer system equipped with the system management mode, a CPU 1 is provided with a program for executing the maintenance of the present system in the system management mode, and an RS232C controller 8 is constituted to be directly accessed from the CPU 1. When system bus abnormality is generated, the CPU 1 executes the remote maintenance of the system from the external line through a MODEM 7 and the RS232C controller 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a remote maintenance system for a system, and in particular, enables restarting and maintenance of a computer system that has a failure such as a system bus hangup or CPU runaway from an external line. And remote maintenance method of the system.

[0002]

2. Description of the Related Art With the progress of networking of computer systems, it is increasingly necessary to perform system maintenance from a remote place via a line. Regarding this, from the past, LAN boards, modems, RS232C from external lines
Through the CP in the same way as the normal transmission and reception of data.
A method is known in which a message is transmitted to U to cause a computer system to perform remote maintenance. Further, as disclosed in Japanese Patent Laid-Open No. 6-44165, there is also known a system having a function of detecting its own failure and automatically restarting when the failure of the system is detected.

[0003]

Of the above-mentioned conventional techniques,
In the former case, when a failure occurs on the system bus, a message may not be transmitted to the CPU. Further, in the latter case, there are problems that the function to be added to the system is large and it cannot be controlled arbitrarily from an external line. The present invention has been made in view of the above circumstances, and an object of the present invention is to solve the above-mentioned problems in the conventional technique and to provide a computer system having a system management mode mainly used as a means for power saving. On the other hand, from an external line, restart the computer system in which a failure such as system bus hangup or CPU runaway occurred, and
It is to provide a remote maintenance method of a system that enables maintenance.

[0004]

The above objects of the present invention are as follows:
In a computer system having a system management mode, the CPU has a program for executing maintenance of its own system under the system management mode, and the RS232C controller is configured to be directly accessible from the CPU, and when a system bus error occurs, This is achieved by a system remote maintenance method characterized by causing a CPU to perform remote system maintenance from an external line via a modem and RS232C.

[0005]

In the remote maintenance system of the system according to the present invention, when data arrives at the RS232C controller from the external line, the CPU shifts to the system management mode, and by executing the program under the system management mode, the CPU is removed from the processor bus. The RS232C data is directly fetched and the maintenance of the own system is performed according to the data content. More specifically, in a computer system having a system management mode function, when an interrupt request is generated from an I / O such as an RS232C controller, the CP
U shifts from the normal operation mode to the system management mode. The CPU executes a program stored in a dedicated memory area in the system management mode, and generally turns on / off an I / O device for power saving.

In the remote maintenance system of the system according to the present invention, the system management mode is used as a means for realizing the system maintenance system. The advantages are as follows. Since the request for shifting to the system management mode to the CPU has a higher priority than other interrupts (NMI, INTR), the processing is performed prior to the illegal interrupt at the time of system failure. In the system management mode, since the program stored in the dedicated memory area is executed, the contents of the program will not be lost due to the runaway CPU when the system fails. Further, in the system remote maintenance method according to the present invention, by having means for directly accessing the RS232C controller from the processor bus in the system management mode, even if a failure occurs on the system bus, the CPU can be operated from an external line. It is possible to receive the data of.

[0007]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a block diagram showing the configuration of a remote system maintenance system according to an embodiment of the present invention. In the figure, 1 is a CPU corresponding to the system management mode, 2 is a processor bus, 3 is a memory controller under the processor bus 2 and corresponding to the system management mode, 3a is a main memory under the control of the memory controller 3, 3b is a dedicated memory area for storing a program executed in the system management mode, 4a is a system management mode compatible interrupt controller for transmitting a system management mode transition request (INTb) to the CPU 1 under the processor bus 2, and 4a. Is the interrupt controller 4
The system bus controller which incorporates a is shown.

Further, 5 is a system bus controlled by the system bus controller 4, 6 is various I / Os connected to the system bus 5, 7 is a modem for transmitting data from an external line to the system, and 8 is RS232C controller, 9a and 9b are RS232C controller 8
A bus transceiver for switching access to the processor bus 2 or the system bus 5 is shown. Note that the bus transceiver (a) 9a is connected to the RS from the processor bus 2 only in the system management mode.
A bus transceiver (b) 9b that enables direct access to the 232C controller 8.
Is a bus transceiver that prohibits access to the RS232C controller 8 from the system bus 5 only in the system management mode.

The operation of the remote system maintenance system according to the present embodiment constructed as described above will be described below with reference to the flow chart shown in FIG. In the system according to the present embodiment, when a system failure occurs,
This fault is detected by an external system (step 1
1), from the external system to the faulty system,
Maintenance data is issued (step 12). This data is accepted by RS232C via modem 7,
It is passed to the RS232C controller 8 (step 13).
When the instruction data arrives from the external line, the RS232C controller 8 issues an interrupt request (INTa) to the interrupt controller 4a (step 14).

In response to this, the interrupt controller 4
a issues an interrupt request (INTb) to CPU1
In response to this, the CPU 1 shifts to the system management mode (step 15) (step 16). CPU1
A maintenance program stored in advance in the system management mode dedicated memory area 3b is retrieved via the memory controller 3 (step 17), and system maintenance is executed by the program (step 1).
8). According to the above-described embodiment, the CPU 1 reads the R data through the processor bus 2 regardless of whether the system bus 5 is abnormal.
It is possible to take out data from the S232C controller 8 and perform predetermined maintenance such as system initialization according to the value of the data.

As described above, this is because the bus transceiver (a) 9a which enables direct access from the processor bus 2 to the RS232C controller 8 only in the system management mode when the instruction data is fetched from the RS232C controller 8 and the system. RS232C from system bus 5 only in management mode
This can be realized by adding a bus transceiver (b) 9b for prohibiting access to the controller 8 to the system. It is needless to say that the above embodiment shows one example of the present invention, and the present invention should not be limited to this.

[0012]

As described above in detail, according to the present invention, a computer system provided with a system management mode has a failure such as a system bus hang or CPU runaway from an external line. The remarkable effect that the system can be restarted and the remote maintenance method of the system that enables maintenance can be realized. More specifically, by using the system management mode for the system maintenance method, it is possible to perform maintenance on the system in which a failure has occurred, and in the system management mode, the RS23 can be directly used by the CPU.
By making it possible to access the 2C controller, the effect that flexible system maintenance according to the data from the external line becomes possible regardless of the presence or absence of a failure is obtained. Further, since the normal I / O interrupt is not used, there is also an effect that it is not necessary to change the device driver on the OS.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a remote system maintenance system according to an embodiment of the present invention.

FIG. 2 is an operation flowchart of the remote system maintenance system according to the embodiment.

[Explanation of symbols]

 1 CPU 2 Processor Bus 3 Memory Controller 3a Main Memory 3b System Management Mode Dedicated Memory 4 System Bus Controller 4a Interrupt Controller 5 System Bus 6 I / O 7 Modem 8 RS232C Controller 9a Bus Transit Bus (a) 9b Bus transceiver (b)

Claims (1)

[Claims] 1. In a computer system having a system management mode, the CPU has a program for executing maintenance of its own system in the system management mode, and the RS232C controller is configured to be directly accessible from the CPU to prevent a system bus error. When it occurs, the modem, RS23 from the external line
A remote maintenance system for a system, characterized in that the CPU is made to perform remote maintenance of the system via 2C.