JP2000357145A - Device and method for network device management - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide accurate network information even in case of a failure in renewing a cache file or if the latest information is not reflected on the cache file. SOLUTION: When a WWW server requests information regarding a network (S2001), a network management program checks whether the cache file is a new one (S2002), and gathers information newly (S2003) when a specific time is elapsed after the file is generated and saves it in the cache file (S2004). It is checked whether or not the cache file has the end tag of an HTML document (S2005) and when not, it is considered that the saving is a failure, thereby deleting the file (S2006).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a network device management apparatus and method for managing devices connected to a computer network, for example.

[0002]

2. Description of the Related Art FIG. 1 shows a case where a network board (NB) 101 for connecting a printer to a network is connected to a printer 102 having an open architecture. The NB 101 is an Ethernet having a coaxial connector on a local area network (LAN) 100.
It is connected via a LAN interface such as an et interface 10Base-2 or 10Base-T with RJ-45.

[0003] A plurality of personal computers (PCs) such as a PC 103 and a PC 104 are also connected to the LAN 100, and these PCs can communicate with the NB 101 under the control of a network operating system. Therefore, one of the PCs, for example, the PC 103
Can be used for network management. Also, the printer 10 connected to the PC 104 is connected to the PC.
5 may be connected.

The LAN 100 has a file server 106
Is connected, and the file server 106 has a large-capacity (for example, 10 billion bytes) network disk 107.
Manage access to files stored in.

[0005] The print server 108 includes a plurality of connected printers 109 or a remote printer 105.
Printer. Further, other peripheral devices (not shown) may be connected to the LAN 100.

[0006] The LAN 100 has a WWW server 1
50 is connected and generated by the network management software installed on the WWW server 150.
An HTML document is displayed using a WWW browser installed on the PC 103, and printer settings made on the WWW browser on the PC 103 are transmitted to a specific printer via network management software on the WWW server 150. You can also.

More specifically, the network shown in FIG. 1 can use network software such as Novell or UNIX software to efficiently communicate between various network members. Although any network software can be used, for example, Novell's NetWare (a registered trademark of Novell, Inc .;
(Omitted) Software can be used. For a detailed description of this software package, please refer to the online documentation included with the NetWare package. It can be purchased from Novell with the NetWare package.

[0008] Briefly, the file server 106
Functions as a file management unit that receives, stores, queues, caches, and transmits files between LAN members. For example, a data file created by each of the PC 103 and the PC 104 is sent to the file server 106, and the file server 1
06 arranges these data files in order, and transmits the arranged data files to one of the printers 109 according to a command from the print server 108.

The PC 103 and the PC 104 respectively generate a data file and a LAN for the generated data file.
It is configured by a general PC capable of transmitting data to the LAN 100, receiving files from the LAN 100, and displaying and / or processing the files. Although a personal computer device is shown in FIG. 1, other computer devices may be included as appropriate to execute the network software. For example, if you are using UNIX software,
Workstations may be included in the network, and these workstations may be used with the illustrated PC under appropriate circumstances.

Typically, a LAN, such as LAN 100, provides services to a relatively local group of users, such as user groups on one floor or multiple consecutive floors within a building. For example, as one user moves away from another user, such as when the user is in another building or another prefecture,
A wide area network (WAN) may be created.
A WAN is basically an aggregation formed by connecting several LANs with a high-speed digital line such as an integrated services digital network (ISDN). Therefore, as shown in FIG.
110 and LAN 120 are modem / transponder 1
30 and the backbone 140,
Form N.

Each LAN includes a dedicated PC,
Further, a file server and a print server may be included as necessary. As shown in FIG.
Are PC111, PC112, file server 113,
Network disk 114, print server 115,
And a printer 116. In contrast, LAN 120 has P
Only C121 and PC122 are included. LAN100, LA
The devices connected to the N110 and the LAN 120 can access the functions of the devices connected to other LANs via the WAN connection.

As a method for managing devices on a network constituting such a large-scale network system, several attempts have been made by a number of standard organizations so far. The International Organization for Standardization (ISO) has established Open System Interconnection,
A generic reference framework called the OSI) model was provided. The OSI model of the network management protocol is based on the Common Management Information Protocol (Comon Management Infor
mation protocol (CMIP). CMIP is a common European network management protocol.

In recent years, a simple network management protocol (SNM) has been used as a network management protocol having higher commonality.
There is a variant protocol related to CMIP called P). (See "Introduction to TCP / IP Network Management for Practical Management," MT Rose, written by Takeshi Nishida, translated by Toppan Co., Ltd., first edition issued on August 20, 1992.) Thus, a network management system includes at least one network management station (NMS), a number of managed nodes, each including an agent, and a network management protocol used by the management stations and agents to exchange management information. included. The user communicates with the agent software on the managed node using the network management software on the NMS,
Data on the network can be obtained and changed.

Here, the agent is software that runs as a background process for each target device. When a user requests management data from a device on the network, the management software sends the object identification information in a management packet or frame to the target agent. The agent interprets the object identification information, extracts data corresponding to the object identification information, puts the data in a packet, and sends it back to the user. Occasionally, a corresponding process is called to retrieve the data.

The agent holds data on its own state in the form of a database. This database is described in MIB (Management Information Ba
se). MIB has a tree-structured data structure.
All nodes are uniquely numbered. This node identifier is referred to as the object identifier (OBJECT IDENTI
FIER).

This MIB has a management information structure (SM
I: Structure of Management Information) and RFC1155 Structure and Identification of Manage
ment Information for TCP / IP-based Internets.

Next, the SNMP protocol will be briefly described. PC (hereinafter referred to as manager) on which the network management utility software is running and SN
Communication with a managed network device (hereinafter, referred to as an agent) on which the MP agent is operating is performed using the SNMP protocol. The SNMP protocol has five types of commands, each of which has a Get-requests command.
t, Get-next-request, Get-re
These are called sponse, Set-request, and Trap.

Get-request and Get-n
ext-request is a command sent from the manager to the agent in order for the manager to obtain the value of the MIB object of the agent. Upon receiving this command, the agent informs the manager of the value of the MIB by using Ge.
Send a t-response command.

Set-request is a command sent from the manager to the agent in order for the manager to set the value of the MIB object of the agent. The agent receiving this command,
A Get-response command is sent to the manager to notify the manager of the setting result.

Trap is a command sent from an agent to a manager in order for the agent to notify the manager of a change in its own state.

The SNMP agent is a PC or printer 102
A network management software which operates on a network board (NB) 101 connected to the PC and operates as a SNMP manager by a PC is often used. However, with the spread of the Internet in recent years, instead of operating dedicated network management software for each client PC, network management software operates on a server, and some systems use WEB as a user interface.

Next, the operation of a general WWW system and the operation of an SNMP management program based on the WWW system will be described with reference to FIG.

In the PC 150, the WWW server program 1
501 is operating, and the disc of PC 150 has HTML
, A large number of WWW page data described using "."

The WWW browser program 1031 running on the PC 103 requests the WWW server program 1051 running on the PC 150 to acquire the specified page in order to display the page specified by the user.

[0025] The WWW server program 1051 is
The specified page data is returned as a response to the request from the W browser program 1031. The WWW browser program 1031 analyzes the acquired page data and displays the page according to the description.

The WWW server program 1051 executes
When the page acquisition request from the W browser program 1031 includes a request via a CGI (Common Gateway Interface), an external script or program is started by a predetermined method of the CGI, and the WWW browser program 10
It receives the page data for responding to the request from 31 and returns it to the WWW browser program 1031.

Next, a case will be described in which the external program started by the CGI is a network management program as in the present invention.

The WWW server program 1051 uses C
Network management program 1052 started by GI
Acquires management data from a device connected to the network, for example, the printer 102, using SNMP. The network management program 1052 generates a page described in HTML based on the acquired management data, and
It returns to the WW server program 1051.

The generated HTML page is stored as a cache file. The network management program 1052 includes a WWW server program 1051
If a certain time has not passed since the cache file was created when an information acquisition request was received from
Returns the cache file as it is without acquiring information by SNMP.

[0030]

As described above, when an external application program such as a network management program responds with data of a cache file,
The data is sent to the WWW browser program of the client that has requested the information from the WWW server. For this reason,
Due to the failure to write the cache file,
Even if the contents of the cache file are incomplete,
The content of the cache file is returned for an information acquisition request generated within a predetermined time after the generation of the cache file.

Also, when a certain network device is deleted from the network, the cache file remains in the server if a certain period of time has not passed since the cache file was generated, and information that does not reflect the latest state is stored in the server. , In response to an information acquisition request from the WWW server program.

For these reasons, a WWW browser program that ultimately receives information from an external application such as a network management program cannot output information that correctly reflects the state of the network.

The present invention has been made in view of the above-mentioned conventional example. Even when the update of the cache file fails, or when the latest information is not reflected in the cache file, It is an object of the present invention to provide a network device management apparatus and method capable of correctly acquiring the above information.

[0034]

In order to achieve the above object, the present invention has the following arrangement. That is, a storage unit for storing network device information relating to a device connected to the network, and, in response to a request for network device information, determining whether the information stored by the storage unit has been stored within a predetermined time. ,
If the information is stored within a predetermined time, responds to the request, and if the predetermined time has elapsed, collects the network information again and stores the network information by the storing means; and Means for deleting the information collected by the means when the storage of the information fails.

Alternatively, storage means for storing network device information relating to a device connected to the network, and network device information collected in response to a request for the network device information, and stored by the storage means based on the collected information. Means for updating information.

Preferably, the network device information includes list information of devices connected to a network.

Preferably, the network device information includes status information of each of the devices connected to the network.

[0038] Preferably, said network device information is responded to said request as an HTML document.

Alternatively, a network system including any one of the above network device management devices and a display device for requesting the device for network device information and displaying a network status based on the network device information for the device.

[0040]

DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment ((Configuration of LAN)) A LAN to which a device managed by network management software is connected will be described below.

FIG. 1 shows a case where a network board (NB) 101 for connecting a printer to a network is connected to a printer 102 having an open architecture. NB 101 is an Ethernet having a coaxial connector on a local area network (LAN) 100.
It is connected via a LAN interface such as an interface 10Base-2 or 10Base-T having RJ-45.

A plurality of personal computers (PCs) such as PC 103 and PC 104 are also connected to LAN 100, and these PCs can communicate with NB 101 under the control of a network operating system. Therefore, one of the PCs, for example, the PC 103
Can be used for network management. Also, the printer 10 connected to the PC 104 is connected to the PC.
5 may be connected.

The LAN 100 has a file server 106
Is connected, and the file server 106 has a large-capacity (for example, 10 billion bytes) network disk 107.
Manage access to files stored in.

The print server 108 includes a plurality of connected printers 109 or a remote printer 105.
Printer. Further, other peripheral devices (not shown) may be connected to the LAN 100.

The LAN 100 has a WWW server 1
50 is connected and generated by the network management software installed on the WWW server 150.
An HTML document is displayed using a WWW browser installed on the PC 103, and printer settings made on the WWW browser on the PC 103 are transmitted to a specific printer via network management software on the WWW server 150. You can also.

More specifically, the network shown in FIG. 1 can use network software such as Novell or UNIX software to efficiently communicate between various network members. Although any network software can be used, for example, Novell's NetWare (a registered trademark of Novell, Inc .;
(Omitted) Software can be used. For a detailed description of this software package, please refer to the online documentation included with the NetWare package. It can be purchased from Novell with the NetWare package.

Briefly, the file server 106
Functions as a file management unit that receives, stores, queues, caches, and transmits files between LAN members. For example, a data file created by each of the PC 103 and the PC 104 is sent to the file server 106, and the file server 1
06 arranges these data files in order, and transmits the arranged data files to one of the printers 109 according to a command from the print server 108.

Each of the PC 103 and the PC 104 generates a data file, and executes the LAN of the generated data file.
It is configured by a general PC capable of transmitting data to the LAN 100, receiving files from the LAN 100, and displaying and / or processing the files. Although a personal computer device is shown in FIG. 1, other computer devices may be included as appropriate to execute the network software. For example, if you are using UNIX software,
Workstations may be included in the network, and these workstations may be used with the illustrated PC under appropriate circumstances.

Typically, a LAN, such as LAN 100, provides services to relatively local groups of users, such as user groups on one floor or multiple consecutive floors in a building. For example, as one user moves away from another user, such as when the user is in another building or another prefecture,
A wide area network (WAN) may be created.
A WAN is basically an aggregation formed by connecting several LANs with a high-speed digital line such as an integrated services digital network (ISDN). Therefore, as shown in FIG.
110 and LAN 120 are modem / transponder 1
30 and the backbone 140,
Form N.

Each LAN includes a dedicated PC,
Further, a file server and a print server may be included as necessary. As shown in FIG.
Are PC111, PC112, file server 113,
Network disk 114, print server 115,
And a printer 116. In contrast, LAN 120 has P
Only C121 and PC122 are included. LAN100, LA
The devices connected to the N110 and the LAN 120 can access the functions of the devices connected to other LANs via the WAN connection.

((Configuration of PC)) FIG. 3 is a block diagram showing the configuration of a PC on which network management software can operate.

In FIG. 3, reference numeral 150 denotes a PC on which network management software operates, and W in FIG.
It is equivalent to the WW server 150. PC150 is ROM
CP executing the network management program stored in the hard disk 302 or the hard disk (HD) 311 or supplied from the floppy disk (FD) 312
U301 is provided to control each device connected to the system bus 304 as a whole.

Reference numeral 303 denotes a RAM, which functions as a main memory, a work area, and the like for the CPU 301. Reference numeral 305 denotes a keyboard controller (KBC).
09 or an instruction input from a pointing device (not shown) or the like. 306 is a CRT controller (CRT
In C), the display of the CRT display (CRT) 310 is controlled. 307 is a disk controller (DKC)
And a hard disk (HD) 311 for storing a boot program, various applications, an editing file, a user file, a network management program, and the like.
And access to a floppy disk (FD) 312. A network interface card (NIC) 308 exchanges data bidirectionally with an agent or a network device via the LAN 100.

((Module Configuration of Network Management Software)) FIG. 4 is a module configuration diagram of a network management program according to the present invention.

The network management software 1062 according to the present invention is stored in the hard disk 311 in FIG. At that time, the CPU 301 uses the RAM 303 as a work area.

In FIG. 4, the network management software 1062 is started from the WWW server program 1061 and is transmitted through the CGI interface 402 to the CGI.
Exchange parameters and HTML documents.

Reference numeral 403 denotes an overall control module, which registers CGI parameters in a parameter module 404 described later, and then, according to a command parameter in the CGI parameters, a system module 405, a device list module 407, and a device detail module described later. 409 is a module for distributing control to any one of 409. If there is an error in the CGI parameter, an HTML document indicating that the CGI parameter has an error may be generated via a template module 412 described below.

A parameter module 404 stores and manages CGI parameters registered by the overall control module 403 in a table format. Other modules can obtain desired parameters from the parameter module 402 as needed.

Reference numeral 405 denotes a system module which controls display and setting of system parameters (for example, an automatic update interval of an HTML document) which defines the operation of the network management software 1062, and generates a related HTML document. is there. The system module 405 obtains the command parameters from the parameter module 404, and when the content of the command parameters is a display request of the system parameters, reads necessary information from the system setting file 406, and reads the system parameters via the template module 412. Generate HTML document for display. If the content of the obtained command parameter is a request for setting a system parameter, the notified system parameter is written to the system setting file 406 and displayed after setting via the template module 412.
Generate HTML documents. Although not shown, the system parameters stored in the system setting file 406 can be read out by each module constituting the network management software 1062 as needed.

A device list module 407 is a module for generating an HTML document indicating a list (device list) of devices searched by a device search module 408 described later. The device list module 407 also controls the processing of the device list display option.

Reference numeral 408 denotes a device search module for searching for a device connected to the network.

Reference numeral 409 denotes a device detail module, which is a CG
A module for controlling and displaying more detailed information on a specific device specified by the I parameter and generating an associated HTML document. The device detail module 409 is used to acquire and set detailed information on the specified device.
Use 10.

Reference numeral 410 denotes a device-specific module, which is a device (a printer, a network interface board, etc.) to be managed by the network management software.
Exist for each. At the time of display, the device-specific module 410 operates to acquire necessary information from the device and set the acquired information in the template module 412. In addition, at the time of setting, the setting value notified by the CGI parameter is converted into a value that can be interpreted by the device and transmitted to the device.

Reference numeral 411 denotes a protocol module.
(Management Information Base) handling, SN
A module for controlling various protocols required for network management software to communicate with devices, such as transmission and reception of MP (Simple Network Management Protocol) packets and control of transport protocols.

Reference numeral 412 denotes a template module.
Is a module for generating an HTML document as an output result of the network management software based on the template file 413 stored in the hard disk 311 of FIG.

The template module 412 has a CGI
Open the template file specified by the parameter, the overall control module 403, the system module 405, the device list module 407, or the device detail module 409, analyze the contents of the template file, and if necessary, the template variables included in the template file. To the overall control module 40
3. Generate an HTML document by substituting the values set by the system module 405, device list module 407, device detail module 409, or device specific module 410,
The program is transmitted to the WWW server program via the interface 402. The value of the template variable used when generating the HTML document or the generated HTML document file is cached in order to reduce the processing time when generating the HTML document for the second and subsequent times based on the same template file The file 414 can be stored on the hard disk 311 in FIG. This network management software 1062 is
Call it etSpot.

((Screen Configuration)) (Device List) FIG. 6 shows a screen called a device list. When the user specifies a predetermined URL indicating this screen on the WWW browser program,
The W server program 1061 activates the network management software 1062, ie, WebNetSpot via the CGI, in order to obtain the resource indicated by the URL, that is, the HTML document for performing the display in FIG.
WebNetSpot searches for devices connected to the network, and for the devices detected by the search, • Device type (601) • Device name (602) • Product name (603) • Network board product name (604) Information such as network address (605) and device status (606) is displayed on the browser.

The device type is classified according to whether it is an ordinary printer or a multifunction device having a copy function, and is displayed as an icon like the device type 601. The device name 602 is a name given to each device by the user.

By clicking the device name 602 on the browser screen, the address of the device is specified. The WWW server obtains the resource specified by the address, that is, WebNetSp, to acquire an HTML document for displaying detailed information of the device as shown in FIG.
Start ot. The details will be described later. Device state 6
06 indicates a state by an icon. The icon changes depending on the importance of the error that has occurred.

((Device Details)) When a device name is clicked in the device list, the IP address of the device is passed to WebNetSpot, and detailed information of the clicked device is obtained based on this information. Displayed in the browser. The information displayed is:-status-equipment information-device information-network board information-protocol information, and these information are displayed on two screens.

FIGS. 7 and 8 show examples of display screens. FIG. 7 shows a state, equipment information, and device information. FIG. 8 shows network board information and protocol information. The screen that displays these device details is divided into a menu on the left and a body on the right. The menu screen on the left has a common appearance in FIGS. 7 and 8, and the screen is switched by using the menu screen. For example, FIG.
When the user clicks on the "network board" indicated by 705, the screen switches to FIG.

((File Configuration of WebNetSpot)) FIG.
Is the file structure of WebNetSpot. Boxes with shadows indicate directories, and boxes with single frames indicate files. 901 is WebNetSpot as a CGI program
Is the root directory. Below this, there are directories for Document, Images, and Template, and there are also WebNetSpot.exe, which is an executable file, and various HTML files.

Under the Document directory 902,
This is for temporarily storing information obtained from the device as a cache file. 903 Imag
Various image files used for displaying information are stored in the es directory. A directory 904 stores a template file. Under this directory are three types of directories. 90
The sys directory indicated by 8 stores a template file for displaying device-independent information such as a device list and an error relationship. A product directory 909 stores a template file related to product-specific information, and exists as many as the number of product types. The information stored in this directory is the state, equipment information, and device information shown in FIG. Information specific to the network board is stored in the NIC directory 910. Information stored in this directory corresponding to the number of types of network boards includes network information and protocol information as shown in FIG. It is. Note that if the same template file can be shared among a plurality of products or network boards, it is not necessary that directories exist by the number of types of products or network boards.

((Structure of Template File)) FIG.
The structure of the template file used in WebNetSpot will be described using. The content of the template file is changed from << TEMPLATE >> tag to << TEMPLATE >>
Described between tags. This is the << HEAD >> tag and the
HEAD block described between </ HEAD> tags, << B
BODY described between ODY >> and </ BODY> tags
It consists of two blocks.

The HEAD block describes a << VARIABLE >> tag that mainly describes information to be acquired from the device as a variable. The BODY block includes an HTML description to be output, an << EMBED >> tag for embedding a value acquired from a device, and the like.

In FIG. 5, it is understood that WebNetSpot only needs to obtain the product name indicated by WNTVAR_DCV_PRODUCT from the device by parsing the HEAD block. WebNetSpot that obtains this information uses SNMP / M
Acquire information from the device by IB. After that, the information obtained from the device is replaced with the << EMBED >> tag having the variable of WNTVAR_DCV_PRODUCT by parsing the BODY block. By performing the parsing as described above for all variables, it is possible to obtain an HTML file to be output.

The following is a list of tags and functions used in the template file.

[0078] ((Cache file)) In WebNetSpot, the acquired information is stored as a cache in order to reduce the number of times of acquiring information by SNMP and shorten the time until it is displayed on a browser. The storage format is the HTML format as shown in FIG. 11, which is the same as the format of the data actually sent to the browser.

The following describes the flow of processing by WebNetSpot, that is, the network management program when an HTML document created from the obtained device information is stored as a cache file.

As shown in FIG. 10, WebNetSpot uses S2
When an information acquisition request is received from the WWW server program in 001, the time at which the cache file was saved is compared with the current time in S2002, and if a certain time set by the user has not elapsed, the cache in S2007 The contents of the file are sent to the browser via the WWW server as it is. The browser performs the display as shown in FIGS. 6, 7, and 8 based on the received HTML document.

On the other hand, if a certain time has passed,
As described above, in S2003, information is newly acquired by SNMP, converted into an HTML file, and passed to the WWW server. Furthermore, in S2004, the cache file
Write the contents of the HTML file. In step S2004, writing to the file may be interrupted for some reason and may fail. When an information acquisition request is received from the server, WebNetSpot outputs the contents of the cache file to the server if the file exists, and if there is an incomplete file due to a failure in writing to the cache file, WWW The browser may make an incorrect display based on the data. So, WebNetSp
In step S2005, ot checks for the existence of </ HTML> as an end tag in the HTML document saved as the cache file created in step S2004. If so, the cache is considered a successful save,
WebNetSpot ends as it is. If not,
If saving to the cache file failed, S
In 2006, the cache file is deleted and the process ends.

As described above, by deleting a cache file that has failed to be saved, it is possible to prevent passing of incomplete network device information to the server, and to display information of an incomplete network. Can be prevented.

[Second Embodiment] Next, in a network having the same configuration as the network system of the first embodiment, always provide the latest network device status information in response to a request from a browser program. Describes the functions of the network management program (WebNetSpot) that can perform

FIG. 12 shows a processing procedure for an information acquisition request from a server by a network management program for performing the above functions.

First, when a predetermined URL is designated from the browser and a request for a device list is received, the server requests the network management program for the network device list. Upon receiving the request in S2001, the network management program (WebNetSpot) searches for a device connected to the network in S2002 when receiving the information acquisition request from the browser.

In S2003, it is checked whether or not a device not found in the current search is described in the device list stored as a cache file. If there is a device not found in the search, that is, if the device has been deleted from the network, S2
At 004, the cache file related to the device is deleted. In step S2005, the current search result in step S2002 is stored in a cache file.
If 0, the device list information is sent to the server.

The server transmits the device list written as the HTML document to the browser that has made the request, and the browser displays the device list as shown in FIG.

Next, a case where a browser requests display of device details will be described. WebNetSpot is S200
In step 6, when the server requests information on the specified device,
In step S2007, information is acquired by SNMP. S20
In 08, in this information acquisition, it is determined whether or not the device has been deleted from the network based on information such as no response from the designated device. If the device has been deleted, the device information of the device is deleted from the cache file in step S2009, and error information indicating that the device has been deleted from the network is output to the server in step S2011. On the other hand, if the device exists, the information acquired in S2010 is output to the server.

The server receiving the information from the network management program passes it to the browser, and the browser displays it.

As described above, the latest network information or device information can always be provided.

[0091]

[Other Embodiments] The present invention can be applied to a system composed of a plurality of devices (for example, a host computer, an interface device, a reader, a printer, etc.), and can be applied to a single device (for example, a copying machine). Machine, facsimile machine, etc.).

Further, an object of the present invention is to realize a storage medium (or a recording medium) which records the program code of the procedure of FIG. 10 or FIG. 12 for realizing the functions of the above-described embodiment.
Is supplied to a system or apparatus, and the computer (or CPU or MPU) of the system or apparatus reads out and executes the program code stored in the storage medium.

In this case, the program code itself read from the storage medium realizes the functions of the above-described embodiment, and the storage medium storing the program code constitutes the present invention. By executing the program code read by the computer, not only the functions of the above-described embodiments are realized, but also an operating system (OS) running on the computer based on the instruction of the program code. This also includes a case where some or all of the actual processing is performed and the functions of the above-described embodiments are realized by the processing.

Further, after the program code read from the storage medium is written into the memory provided in the function expansion card inserted into the computer or the function expansion unit connected to the computer, the program code is read based on the instruction of the program code. This also includes the case where the CPU provided in the function expansion card or the function expansion unit performs part or all of the actual processing, and the processing realizes the functions of the above-described embodiments.

[0095]

As described above, according to the present invention, erroneous information can be prevented from being output from the cache file without leaving the contents of the cache file that failed to be saved.

Further, it is possible to always provide the latest information.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a LAN.

FIG. 2 is a configuration diagram of a general WWW system.

FIG. 3 shows a P on which network management software can operate.
It is a block diagram of C.

FIG. 4 is a module configuration diagram of network management software.

FIG. 5 is a diagram showing an example of a template file.

FIG. 6 is a diagram illustrating an example of a device list.

FIG. 7 is a diagram illustrating an example of a device list.

FIG. 8 is a diagram illustrating an example of a device list.

FIG. 9 is a diagram illustrating a file configuration of network management software.

FIG. 10 is a flowchart illustrating a cache file deletion method according to the first embodiment of the present invention.

FIG. 11 is a diagram showing a description example of an HTML file according to the first embodiment of the present invention.

FIG. 12 is a flowchart illustrating a cache file deletion method according to a second embodiment of the present invention.

[Explanation of symbols]

Reference Signs List 100 Local area network (LAN) 101 Network board (NB) 102 Printer having open architecture 103 Personal computer (PC) connected to LAN 100 104 Personal computer (PC) connected to LAN 100 105 Connected to PC 104 Printer 106 File server 107 connected to LAN 100 Network disk 108 included in LAN 100 Print server 109 included in LAN 100 Printer connected to print server 108 110 Local area network (LAN) 111 Personal computer connected to LAN 110 (PC) 112 Personal computer (PC) connected to LAN 110 13 File Server Connected to LAN 110 114 Network Disk Included in LAN 110 115 Print Server Included in LAN 110 116 Printer Connected to Print Server 110 120 Local Area Network (LAN) 121 Personal Computer (PC) Connected to LAN 120 122) Personal computer (PC) connected to LAN 120 130a Modulation / demodulation (MODEM) / transponder 130b Modulation / demodulation (MODEM) / transponder 140 Backbone 150 Personal computer (PC) connected to LAN 100 and running WWW server 301 CPU that executes the network management program supplied from FD 212 302 PC20 Keyboard controller (KB system bus 305 PC 200 of RAM 304 PC 200 of ROM 303 PC 200 of
C) 306 CRT controller (CRTC) of PC 200 307 Disk controller (DKC) of PC 200 308 Network interface card (NIC) of PC 200 309 Keyboard (KB) of PC 200 310 CRT display (CRT) of PC 200 311 Hard disk (HD) of PC 200 312 Floppy disk drive (FD) 402 CGI interface 403 Overall control module 404 Parameter module 405 System module 406 System setting file 407 Device list module 408 Device search module 409 Device detail module 410 Device specific module 411 Protocol module 412 Template module 413 Template file 414 Cache file 901 WebNetSpot directory storing network management software WebNetSpot 902 Document directory storing cache file 903 Images directory storing image file 904 Template directory storing template file 905 Network management software WebNetSpot 906 HTML file 907 Image file 908 Common SYS directory for storing template files used 909 PRODUCT directory for storing device-dependent template files 910 NIC directory for storing network board-dependent template files 911 Template files 912 Template files 913 Template file 1031 WWW browser program 1051 WWW server program 1052 Network management program 1061 WWW server program 1062 Network management software

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Claims (13)

[Claims] 1. A storage means for storing network device information relating to a device connected to a network, and information stored by said storage means in response to a request for network device information, stored within a predetermined time. If the information is stored within a predetermined time, it is responded to the request, and if the predetermined time has elapsed, network information is newly collected and stored by the storage means. And a means for deleting the information collected by the collecting means when the information fails to be stored. 2. A storage unit for storing network device information relating to a device connected to a network, and collecting network device information in response to a request for the network device information, and storing the network device information based on the collected information. Means for updating information. 3. The network device management apparatus according to claim 1, wherein the network device information includes list information of devices connected to a network. 4. The network device management apparatus according to claim 1, wherein the network device information includes status information of each device connected to a network. 5. The network device information includes an HT
3. The network device management apparatus according to claim 1, wherein a response is made to the request as an ML document. 6. The network device management apparatus according to claim 1 or 2, and a display device for requesting the device for network device information and displaying a network status based on the network device information for the device. A network system comprising: 7. In response to a request for network device information relating to a device connected to a network, it is determined whether the network device information stored by the storage unit has been stored within a predetermined time, and stored within the predetermined time. If the information is the response to the request, and if a predetermined time has elapsed, a collection step of collecting network information again and storing it by the storage unit; and information collected by the collection step. And deleting the information when the storage of the network device has failed. 8. A network, comprising: collecting network device information in response to a request for network device information relating to a device connected to a network; and updating the information stored by the storage unit with the collected information. Device management method. 9. The network device management method according to claim 7, wherein the network device information includes list information of devices connected to a network. 10. The network device management method according to claim 7, wherein the network device information includes status information of each device connected to a network. 11. The network device information may be H
9. The network device management method according to claim 7, wherein a response is made to the request as a TML document. 12. A storage means for storing network device information relating to a device connected to a network by a computer, and the information stored by said storage means is stored within a predetermined time in response to a request for network device information. If the information is stored within a predetermined time, it is responded to the request.If the information has passed a predetermined time or more, network information is newly collected and stored by the storage unit. A computer-readable storage medium storing a computer program for realizing a collection unit for causing the collection unit to delete the information collected by the collection unit when the storage fails. 13. A storage means for storing network device information relating to a device connected to a network by a computer; collecting network device information in response to a request for network device information; A computer-readable storage medium storing a computer program for realizing means for updating stored information.