JP2001229070A - Directory server retrieving device and recording medium with retrieval program in the same device recorded - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a directory server retrieving device capable of retrieving an accessible directory server without mounting the switching function of the directory server on an application. SOLUTION: This directory server retrieving device 1 is provided with an access requesting means 2 which requests access based on a directory server list file 6 in response to an access request to a directory server, an access judging means 3 which judges whether or not the directory server is made accessible, based on a judgment reference definition file 7, an access switching means 4 which switches the access to the other directory server when the access fails, and an access responding means 5 which transmits an access response when the access succeeds, and transmits an error response when all the directory servers can not be accessed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a directory server search device for searching for access to a clustered directory server, and is capable of searching for an accessible directory server from a plurality of directory servers. The present invention relates to a directory server search device and a recording medium storing a search program in the directory server search device.

[0002]

2. Description of the Related Art LDAP (Lightweight Directory) is a protocol for accessing a directory server.
In a directory server that implements the Access Protocol (v3) protocol, clustering for duplicating or tripling the directory server and the directory database is conventionally performed for the purpose of distributing the load of the server and the security of the stored information. Was.

A conventional method for searching such a clustered directory server is shown in FIG.
It will be described based on.

Conventionally, a client terminal device 61
Is connected to clustered (duplicated in FIG. 6) directory servers 63 and 64 via a network 62, and the directory servers 63 and 64 manage directory databases 65 and 66, respectively.

[0005] The directory databases 65 and 66
6 manages information in a hierarchical structure in the form of a directory tree, and FIG. 6 shows an example in which the organization of company A is managed in a hierarchical structure.

In the directory tree shown in FIG. 6, Company A has two factories, an α factory and a β factory. The β factory has business units in the electric power field, the distribution field, the finance field, and the like.
This indicates that there are employees of Yamada and Sato in the electric power field.

[0007] Applications that access such a directory server include an application for retrieving the mail address of each employee and an application using a workflow system. In such an application, when the access to the directory server 63 is requested and the directory server 63 is down or cannot be accessed due to a busy state or the like, the access request is switched to access the directory server 64. Such functions were implemented respectively.

[0008]

However, as described above, in the related art, each application has performed the switching process of the directory server. Therefore, unless each application has a function for switching the directory server. did not become.

For example, if any of the applications A1, A2,..., An of the client 61 includes a process for accessing the directory server, a directory server switching function is implemented in each of those applications. I had to.

Therefore, when a developer creates an application including a process for accessing a directory server, the developer must repeatedly perform a task of implementing a directory server switching function every time the application is created. There was a problem.

In particular, when the directory server is running and cannot be accessed, for example, when the directory server is busy, the server can switch the directory server, but the directory server may be down. In such a case, the server cannot perform the switching process. In such a case, the server cannot be switched unless each application has a function of switching the directory server.

[0012] Therefore, the developer must implement a server switching function every time an application including a process for accessing the directory server is created, and thus has to repeatedly perform a complicated operation.

The present invention has been made in view of the above circumstances, and has as its object to provide a directory server which can search and access an accessible directory server without implementing a directory server switching function in an application. It is an object of the present invention to provide a recording medium that records a search program in a search device and a directory server search device.

[0014]

In order to achieve the above object, a directory server search device according to the first aspect of the present invention comprises a plurality of clustered clusters in response to an access request from an application to a directory server. An access requesting directory server to be an access request target is selected from the directory servers, and the access requesting means for requesting the access and the access target directory server requested by the access requesting means are accessible. Access judging means for judging whether or not the access target directory server is inaccessible when the access judging means judges that the directory server is inaccessible; and an access switching means for switching access to another directory server. When it is determined that the directory server to be accessed is accessible, an access response indicating that access is successful is transmitted to the application, and when it is determined that all directory servers are inaccessible, the application is notified to the application. Access response means for responding to an error.

According to the first aspect of the present invention, each application can access a directory server that can be accessed from among a plurality of directory servers without implementing a function of searching the directory server. Load distribution from a plurality of clients can be realized.

A directory server search device according to a second aspect of the present invention is characterized in that the directory server search device is mounted on a client terminal device.

According to the second aspect of the present invention, since the directory server search device is installed for each client, even if access requests to the directory server increase, it is possible to process those access requests. .

According to the third aspect of the present invention, a storage medium storing a search program in the directory server search device includes a plurality of clustered directory servers in response to an access request to the directory server from an application. An access request target directory server is selected as an access request target, and an access request process for requesting access is determined, and it is determined whether the access target directory server requested to be accessed in the access request process is accessible. An access determining process, an access switching process for switching access to another directory server when the access target directory server is determined to be inaccessible in the access determining process, and the access determining process When it is determined that the directory server to be accessed is accessible, an access response indicating that the access is successful is transmitted to the application, and when it is determined that all directory servers are inaccessible, an error is issued to the application. And an access response process for responding to the request.

According to the third aspect of the present invention, each application can access a directory server that can be accessed from a plurality of directory servers without implementing a function of searching the directory server. Load distribution from a plurality of clients can be realized.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a first embodiment of a directory server search device according to the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of the directory server search device according to this embodiment. As shown in FIG. 1, the directory server search device 1 includes a plurality of directory servers DS1, DS in response to a directory server search request by an application of a client C.
, DSn, access requesting means 2 for making an access request to one directory server, access determining means 3 for determining whether or not access to this directory server was successful, and this access determining means If it is determined in step 3 that the directory server to be accessed is not in an accessible state, the access switching means 4 switches the access to another directory server.
When the access determining means 3 determines that the access to the access target directory server is successful, it transmits an access response indicating that the access has been completed, and when it is determined that all the directory servers are inaccessible, the client Response means 5 for transmitting an error response to a plurality of directory servers DS
1, DS2,... Directory server list file 6 storing information such as the host name and port number of DSn
And a criterion definition file 7 for storing a criterion for determining whether or not access to the directory server has been successful.

Further, the directory server search device 1 includes a plurality of clustered directory servers DS.
1, DS2,..., DSn, and these directory servers DS1, DS2,.
Are the directory databases DD1 and DD, respectively.
2,... DDn are managed.

Also, the directory server search device 1
It is connected to the client C via the network 8.

The directory server search device 1
An ordinary computer system including a CPU for performing various types of processing and storage means for storing instructions for the processing is included. Instructions and timing constraints for the respective processes of the access requesting unit 2, the access determining unit 3, the access switching unit 4, and the access responding unit 5 included in the directory server search device 1 are stored in a storage unit. And is executed.

Next, a directory server search process in the directory server search device of the present embodiment will be described with reference to the flowchart of FIG.

First, when there is a search request from the application of the client C to the directory servers DS1,... DSn (S201), the access request means 2 of the directory server search device 1 reads the directory server list file 6 (S202). The directory server list file 6 describes the host names and port numbers of the directory servers DS1,..., DSn. Here, an example of the directory server list file 6 is shown in FIG. In FIG. 3, DS1, DS2,..., DSn are described as host names, and a port number is 38 for each host name.
9, 389, ..., 9000 are described.

Next, the access judgment means 3 reads the judgment criterion definition file 7 (S203). This determination criterion definition file 7 includes directory servers DS1,.
Information for the access determining means 3 to determine whether or not access to Sn has succeeded is described. here,
FIG. 4 shows an example of the criterion definition file 7.

In FIG. 4, "cycle" refers to the upper limit of the number of cycles for repeatedly making an access request when the access request from directory server DS1 to directory server DSn is one cycle.
Therefore, in the case of “cycle = 2”, it means that the access request from the directory servers DS1 to DSn is repeated up to two cycles, but does not enter the third cycle.

The "timeout" refers to a response timeout period for waiting for a response from one directory server. Therefore, "timeout = 60
In the case of "0", if there is no response from the directory server even after waiting for a response for 600 seconds, it is determined that a timeout has occurred.

Further, in FIG. 4, the number of directory servers is described as Sv = n.

Then, in steps S203 and S204, when the reading of each of the directory server list file 6 and the criterion definition file 7 is completed,
The access request unit 2 requests access by using the directory server described at the head of the directory server list file 6 as the access target directory server (S204). Therefore, in the case of the directory server list file in FIG. 3, since the directory server DS1 is described at the top, the access is first requested with the directory server DS1 as the access target directory server.

The access determining means 3 first determines whether or not there is an error response due to a reason such as the directory server DS1 being down as a result of the access request (S205), and then the directory server DS1.
It is determined whether 1 has timed out due to a busy state or the like (S206). For example, since timeout = 600 is described in the criterion definition file 7 in FIG. 4, if there is no response from the directory server DS1 for 600 seconds, it is determined that a timeout has occurred.

In steps S205 and S206, if there is no error response and there is no timeout, the access determining means 3 determines that the access was successful, and the access response means 5
An access response to the effect that access to S1 has been completed is transmitted (S207), and the directory server search processing by the directory server search device 1 ends.

In steps S205 and S206, when the access judging means 3 receives an error response or judges that a time-out has occurred, the upper limit value c of the number of cycles to repeat the next directory server search is set.
Then, it is determined whether or not the value exceeds ycycle (S208).
The upper limit cycle of the number of cycles is an upper limit of the number of times that the cycle is repeated with one cycle of an access request from the directory server DS1 to the directory server DSn. In the case of FIG. , But the third cycle is not performed.

In this case, since the cycle is still the first cycle, the cycle becomes equal to or less than the upper limit cycle, and the process proceeds to step S211 where the access switching means 4 switches the directory server to be accessed and requests access (S211). ).

Here, the access switching means 4 switches the access in the order described in the directory server list file 6. Therefore, in the case of FIG. 3, the access switching means 4 switches from the directory server DS1 to the next directory server DS2. Thereafter, if the access is not successful, the directory server is sequentially switched from DS2 to DSn.

Then, the access judging means 3 obtains the result of the access request to the switched directory server,
It is determined whether there is an error response due to a reason such as the server being down from the directory server (S212), and whether a timeout has occurred due to a busy state or the like (S213).

Here, if there is no error response and there is no timeout, it is determined that the access has succeeded, and the flow advances to step S207 to transmit an access response to the client C (S207). The directory server search process ends.

Steps S212 and S2
In 13, when the access determining means 3 determines that an error response or timeout has occurred, it is determined whether the access determining means 3 has switched to all directory servers (S 214). This corresponds to the number of servers Sv described in the criterion definition file 7,
Judgment is made based on whether or not the number of times of switching has been reached. Therefore, in the case of FIG. 1, since the number of servers is n, Sv = n is described in the criterion definition file of FIG. It is determined whether or not all directory servers have been switched.

Here, if the switching has not been completed for all directory servers, the process proceeds to step S211 to be switched to the next directory server, and if the switching has been completed for all directory servers, the process returns to step S208 and returns to step S208. It is determined whether or not to enter the cycle.

Here, in step S208, when the value exceeds the upper limit cycle, the access judging means 3
Means that all directory servers DS1, DS2,.
.., It is determined that DSn is not in an accessible state (S
209) In response to this determination, the access response means 5 transmits an error response indicating that the directory server could not be accessed to the application of the client C requesting the search (S210). Is terminated.

If it is determined in step S208 that the value does not exceed the upper limit cycle, the next cycle is entered and the above-described search processing is continued, and the access response means 5 returns the access response in step S207 or the error response in step S210. Until is transmitted to the client C, the directory server search processing by the directory server search device 1 is continued.

As described above, the directory server search device of the present embodiment performs a process of searching for an accessible directory server in response to a directory server search request from each application. Therefore, each application searches the directory server. It is possible to access a directory server without implementing a function to perform this.

Next, a directory server search device according to a second embodiment will be described with reference to FIG.

As shown in FIG. 5, the directory server search device 1 according to the present embodiment differs from the first embodiment shown in FIG. 1 only in that it is mounted on the terminal device of the client C.

However, in the first embodiment, since the directory server search device 1 is provided on the directory server side, there is a problem that it is impossible to respond to a search request from many client applications. On the other hand, in the second embodiment, since the directory server search device 1 is mounted on each of the clients C1,..., Cn, such a problem can be solved.

Therefore, the directory server search device 1 according to the second embodiment searches for an accessible directory server in response to a directory server search request from each application, as in the first embodiment. Since the processing is performed, each application can access the directory server without implementing a function of searching the directory server.

Further, since the directory server search device according to the second embodiment is installed for each client, even if access requests to the directory server increase, it is possible to process those access requests. .

A program for realizing each process of the directory server search device described above can be stored in a recording medium, and by reading this recording medium by a computer system, the program is executed to execute the computer. The respective processes of the directory server search device described above can be realized while controlling.
Here, the recording medium includes a device capable of recording a program, such as a memory device, a magnetic disk device, and an optical disk device.

[0050]

As described above, according to the directory server search device and the storage medium storing the search program in the directory server search device of the present invention,
Each application can access a directory server that can be accessed from multiple directory servers without implementing a function to search the directory server, and the directory server can realize load distribution from multiple clients. .

Further, by mounting the directory server search device of the present invention for each client, even if access requests to the directory server increase, it becomes possible to process those access requests.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the configuration of a first embodiment of a directory server search device according to the present invention.

FIG. 2 is a flowchart illustrating a directory server search process in the directory server search device illustrated in FIG. 1;

FIG. 3 is a diagram showing an example of a directory server list file shown in FIG.

FIG. 4 is a diagram showing an example of a criterion definition file shown in FIG.

FIG. 5 is a block diagram showing the configuration of a second embodiment of the directory server search device according to the present invention.

FIG. 6 is a diagram for explaining a conventional directory server search process.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Directory server search apparatus 2 Access request means 3 Access judgment means 4 Access switching means 5 Access response means 6 Directory server list file 7 Judgment standard definition file 8, 62 Network 61, C, C1, ..., Cn client 63, 64 , DS1, DS2, ..., DSn Directory server 65, 66, DD1, DD2, ... DDn Directory database A1, A2, ..., An application

Claims (3)

[Claims] In response to an access request to a directory server from an application, an access target directory server to which an access request is to be made is selected from a plurality of clustered directory servers.
Access requesting means for requesting access; access determining means for determining whether or not the access target directory server requested by the access requesting means is accessible; and the access determining directory server using the access determining means. Access switching means for switching access to another directory server when it is determined that the access target directory server is not accessible, and the access is successful when the access determination means determines that the access target directory server is in an accessible state. Access response means for transmitting an access response to the effect to the application, and when it is determined that all the directory servers are inaccessible, an error response to the application is provided. Directory server search device and butterflies. 2. The directory server search device according to claim 1, wherein the directory server search device is mounted on a client terminal device. 3. In response to an access request to a directory server from an application, an access target directory server targeted for the access request is selected from a plurality of clustered directory servers.
Access request processing for requesting access; access determination processing for determining whether or not the access target directory server requested in the access request processing is accessible; and the access target directory server in the access determination processing. Is determined to be inaccessible, an access switching process for switching access to another directory server, and the access is successful when the access determination process determines that the access target directory server is accessible. Transmitting an access response to the application to the effect that all directory servers are inaccessible when the directory server is determined to be inaccessible. Recording medium recording a search program in the directory server retrieval apparatus according to symptoms.