JP3807240B2 - E-mail system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electronic mail server device operated on the Internet.
[0002]
[Prior art]
There are various e-mail services in recent Internet connection services.
Among them, there is a service for accessing the same mail data from various client computers including mobile phones. Typical services include a service using a protocol called IMAP4 and a mail service using a web browsing function. However, due to a sudden increase in the number of users and uneven access to specific mail data from many users, the hardware of the server that manages this mail data may fail. The server service that manages mail data may be stopped to maintain the server.
[0003]
For example, in the electronic mail system described in Japanese Patent Application Laid-Open No. 9-331354, when moving mail data, it is necessary to move a large number of mail assets at the same time. Since copying and deletion in proportion to property occur, there is a problem that it takes a considerable time to complete the movement. Therefore, in order to solve this problem, a period for holding the same mail property at the source and destination is provided, and the user accesses only the source until a predetermined date and time, and accesses the destination server after the predetermined date and time. We are trying to solve this problem by switching access rights.
[0004]
[Problems to be solved by the invention]
However, in the conventional e-mail system, when managing e-mails on a mail server, not only reading e-mails from the server, but also rewriting flags indicating a plurality of states or changing a logical structure called a managed folder Therefore, there is a case where the operation to the mail server during that time cannot be correctly reflected only by accessing the migration source during copying and accessing the migration destination after copying.
[0005]
For example, if you change the flag that indicates the status of mail data after copying has started, or move a folder, the status will not be reflected in the destination mail data. When the destination is accessed after a certain time, there is a problem that the previous operation is invalidated. In such a case, there is a problem that the service must be stopped once.
[0006]
The present invention has been made to solve the above-described problems. In the method of managing mail on the server, it is assumed that a plurality of mail data management servers contain a large number of mails of the same user. By using multiple servers temporarily to make it appear as if it is a single server, the server configuration is changed, that is, the server configuration is changed, the user to which the user belongs is moved, An object of the present invention is to provide an e-mail system that does not require the service to be stopped even when the hardware is replaced.
[0007]
[Means for Solving the Problems]
The first invention executes a process based on an access request from a user transmitted via a network, and manages a plurality of mail data management servers for managing mail data for each user,
Information of a mail data management server that stores user information of the user and manages user mail data corresponding to the user information when the user information transmitted from the user exists in the stored user information A user authentication server to obtain
Connected to the plurality of mail data management servers via a network, acquires the access contents transmitted from the user, and acquires the access contents acquired and the information of the mail data management server acquired by the user authentication server. In an e-mail system including a front-end server that identifies a mail data management server to be accessed based on and returns a processing result executed by the identified mail data management server to the user,
The front-end server connects a new mail data management server to the network during operation of the plurality of mail data management servers, and the users in the plurality of mail data management servers operating on the new mail data management server. The mail data is copied, the information that the new mail data management server is connected is added to the management table held by itself, and the plurality of mail data that are operating on the new mail data management server are added to the user information. A mail server access management unit for adding information obtained by copying user mail data in the server is provided.
[0008]
According to a second aspect of the present invention, when a user accesses the new mail data management server while copying the user's mail data, the new mail data management server stores the user on the basis of the access content protocol being copied. A mail server access management unit for copying the mail data.
[0009]
According to a third aspect of the present invention, when all of the user's mail data is copied, the mail data management server information stored in the user is returned to the normal state before copying, and the mail data management server in the user information is restored. Is provided with a mail server access management unit for changing the information to new mail data management server information.
[0010]
The fourth invention determines whether or not there is one piece of mail data management server information acquired by the user authentication server, and when there are a plurality of pieces of mail data management server information, the plurality of pieces of mail data management A mail server access management unit is provided that accesses the server, synthesizes processing results executed by the plurality of mail data management servers in accordance with the access request, takes a history of access contents, and returns the history to the user.
[0011]
According to a fifth aspect of the present invention, there is provided a first configuration including a folder name corresponding to a user's mail data, unique ID information and data in the folder, based on a processing result executed by the specific mail data management server. A correspondence table is created for each mail data management server, and data of the same folder name and the same ID information is searched from the plurality of first correspondence tables thus created. A mail server that synthesizes the processing results by creating a second correspondence table composed of folder names, ID information, and data that do not overlap with the same ID information and that do not contradict each other. An access management unit is provided.
[0012]
A sixth invention includes a mail server access management unit that determines a protocol of an access request from a user and identifies a mail data management server based on the protocol.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Embodiment 1 FIG.
Embodiment 1 of the present invention will be described below with reference to the drawings.
FIG. 1 is a configuration diagram of the electronic mail system according to the first embodiment. In FIG. 1, 1 is the Internet or intranet as a network for connecting a user or another mail system to this system, 2 is monitoring the access request from the user, and when the access request comes, the work determined in order A front-end server that performs processing, distributes processing as necessary, and synthesizes the results, 3 is a user authentication server that authenticates that the user who requested the access is a correct user, and 4 is user information used by the user authentication server 3 Is a user database (user DB) in which is stored, 5 is a mail data management server composed of one or more servers that execute distributed processing, and 6 is a network that connects these servers.
Here, the physical functions of each server, which is a component, may be realized on a single computer.
[0014]
Next, a software configuration for operating each component of the electronic mail system will be described.
In FIG. 1, 11 is on the front-end server 2 to which an access request is made from the Internet or the intranet 1 to which the user or other mail system is connected to this system, and an access request from the user or another mail system is received. An access monitoring unit 12 for monitoring is located on the user authentication server 3 and is accessed from the Internet or an intranet, and a user authentication unit for authenticating a user when a mail addressed to the mail system is sent. 13 is a user authentication server 3 is a user database management unit (user DB management unit) for managing the user DB 4 used for user authentication, and 14 is a front-end server 2 for analyzing the contents of access from the user. , 15 is on the front-end server 2 and is based on the result of command analysis. A mail server access management unit that identifies and distributes the mail data management server 5 and sends a request to a plurality of mail data management servers 5 and summarizes the results when accessing the mail data; 16 is a mail data management server 5 is a plurality of mail data management units that actually manage mail data for each user.
[0015]
2 is a flowchart showing an operation procedure of the electronic mail system according to the first embodiment, FIG. 3 is a flowchart showing an operation procedure at the time of server distribution described in the flowchart of FIG. 3, and FIG. 4 is a plurality of flowcharts described in the flowchart of FIG. FIG. 5 is a flowchart showing an operation procedure for combining response results of a plurality of mail data management servers 5 described in the flowchart of FIG. 3, and FIG. 6 is a mail data management server. FIG. 7 is a flowchart showing the operation procedure of the data copy end process of the mail data management server 5.
[0016]
The operation will be described with reference to the flowcharts of FIGS.
First, in the flowchart of FIG. 2, the access monitoring unit 11 monitors an access request from a user or another mail server, that is, the access monitoring unit 11 monitors an access request from the Internet or the intranet 11 for each access port. If there is, a response is immediately returned to the other party to acquire user information (step S1).
[0017]
Next, the user authentication unit 12 determines whether the user information of the user corresponding to the user information exists in the user DB 4 based on the user information acquired by the access monitoring unit 11, and if necessary, It is determined whether the user's password is correct. If there is no problem, the information of the mail data management server 5 that holds the user's mail among the plurality of mail data management servers 5 that manage the user's mail is used as the user authentication server 3. (Step S2).
On the other hand, if it is determined in step S2 that the user is not correct, the other party is notified of this (step S6), and the connection is terminated.
[0018]
The information related to the mail data management server 5 is usually one mail data management server 5 and does not change for each user, but the number of users is large and cannot be managed by one mail data management server 5. In this case, users are distributed to a plurality of mail data management servers 5, and in this case, the information is different for each user.
In addition, information regarding the mail data management server 5 may include information on the mail data management server 5 of the user who should be originally and flag information indicating that the migration is in progress to replace the server.
[0019]
Next, the command analysis unit 14 analyzes the access contents from the user (step S3). In the analysis method, the corresponding protocol is limited by the port number from which the access request has been made, and if the content is not understood by the protocol, it is processed as an error.
As protocols, for example, the IMAP4 protocol corresponds to the port number 143 of the computer network, and the protocol called SMTP corresponds to the port number 25, which is used as an Internet standard. These protocols are examples, and neither the port number nor the protocol is limited.
In step S3, there is a command that can be recognized for each protocol, and it is analyzed according to the input data to determine what the command is actually.
[0020]
Next, the mail server access management unit 15 identifies and accesses the mail data management server 5 based on the access contents analyzed in step 3 and the information of the mail data management server 5 acquired in step 2, Processing according to the request is performed (step S4, step S5).
In step S5, the content specified by the protocol is executed by the mail data management unit 16 on the mail data management server 5. For example, this server may be an SMTP server or an IMAP4 server.
Further, the analysis in step S3 specifically refers to the character string after the space by determining whether or not the character string from the beginning of the line until the space comes is read as a command. Is considered as an argument.
[0021]
Next, a detailed processing operation of the server distribution processing in step S4 that operates on the front-end server 2 will be described with reference to FIG.
First, when the mail server access management unit 15 receives an access request command from a user or another mail server, the mail server access management unit 15 takes out the information of the mail data management server 5 regarding the user acquired at the time of user authentication (step S11).
Subsequently, the mail server access management unit 15 determines whether or not the information of the mail data management server 5 is one server (step S12).
[0022]
Here, in normal operation, it is considered that there is only one mail data management server 5 that manages the mail data of one user. The process proceeds to step S15, and the requested content is directly applied to the corresponding mail data management server. The mail data management server 5 performs processing according to the corresponding IMAP4 command or SMTP command.
Thereafter, the processing result obtained by the mail data management server 5 is returned to the requesting user and other mail servers according to the route for which the access request has been made without doing anything (step S16).
[0023]
If there are a plurality of mail data management servers 5 in step S12, the user's data is being migrated, indicating that the data is in the plurality of mail data management servers 5. In such a case, the mail server access management unit 15 issues an access request to a plurality of mail data management servers 5 (step S13), and the plurality of mail data management servers 5 perform processing and access the obtained processing results. The result is combined with the processing result according to the request, and the history of what access is made is sent back to the user (step S14).
[0024]
Next, a detailed processing operation of the processing for issuing a request to the plurality of mail data management servers 5 in step 13 will be described with reference to FIG.
First, it is determined what protocol is used (step S21). For example, in the case of SMTP, an external mail client or server is trying to send mail according to a mail transfer protocol, that is, a new mail is being sent. When copying from the old mail data management server 5 to the new mail data management server 5, only the new mail data management server 5 is accessed and a request is sent to the new mail data management server 5. (Step S24). This prevents mails from arriving and disappearing after copying is complete.
[0025]
Next, the response from the mail data management server 5 is returned to the request source as it is (step S25).
Further, in the case of a protocol for accessing stored mail data such as IMAP4 or POP3, it is necessary to access mail data that exists only in the old mail data management server 5 and mail data in the new mail data management server 5. Therefore, an access request is issued to both the new and old mail data management servers 5 (step S22).
This is because, during copying, mail exists on both mail data management servers 5 until copying is completed, and new mail exists only on the new server. This is because it cannot be guaranteed that all mail will exist on the new server.
[0026]
Subsequently, each mail data management server 5 performs processing in response to each request, and returns the processing result (step S23). For example, if this request is a protocol of IMAP4 and requests a list of contents of a folder called “inbox” that is a standard inbox, contents of a folder called “inbox” that is a standard inbox in each mail data management server 5 The process of performing a list of.
[0027]
Next, a processing operation for synthesizing the result obtained in step S14 of FIG. 3 returned from the plurality of mail data management servers 5 by the mail server access management unit 15 on the front-end server 2 will be described with reference to FIG. explain.
First, responses from each mail data management server 5 are collected (step S31). This response is, for example, UID information that is a unique ID in the folder indicating the mail data or the mail data itself together with information indicating whether the request has succeeded or failed. Here, for example, in the IMAP4 server which is an example of the mail data management server 5, the UID information indicating the mail data is a number uniquely determined by a folder for managing mail, and the same UID code sent from a plurality of servers. If mail data with the same folder information is the same mail data, this means that the same mail data is only copied
[0028]
Next, in response to a response from one mail data management server 5, the creation of a correspondence table of folder names, UIDs, and actual data is repeated, and this correspondence table is created for each mail data management server 5. (Step S32).
Subsequently, the plurality of tables created in step S32 are compared to find data having the same folder name and the same UID information (step S33).
[0029]
Next, it is assumed that the flag information is different despite the same mail data. In this case, the contents of the old mail data management server 5 before copying are prioritized (step S34). The reason for this is that, as will be described later with reference to FIG. 6, in the data copy operation of the mail data management server 5, if there is a contradiction in the information of the mail data management server 5, the old mail data management before copying This is because only the server 5 is operated and the new mail data management server 5 is not operated.
Next, a correspondence table of folder names, UIDs, and actual data is created in which duplicates of the same mail data are omitted and no contradiction occurs, that is, there is no difference (step S35).
Further, a result of synthesis is returned by returning a response based on this correspondence table (step S36).
[0030]
Next, the mail data copy processing operation of the mail data management server 5 will be described with reference to FIG.
This copy does not stop the service, for example, when the user's disk capacity is almost full, when replacing a machine to improve performance, or when moving user information to a new machine. This is to copy user information.
First, a new mail data management server is physically connected to the running system and connected to the network. Thereby, the connection of a new mail data management server can be added (step S41).
[0031]
Next, the setting of the mail server access management unit 15 is changed (step S42). For example, for TCP / IP connection, assign an IP address, write the information that the new mail data management server 5 is added and the address to the table of the mail server access management unit 15 after connecting with a LAN cable. Thus, the mail data management server 5 can be added. At this point, since each user is not in a moving state, all access requests are processed for the old mail data management server 5.
[0032]
Next, the user is selected and the copy status is set (step S43).
Here, for example, one user is selected one by one from the user DB 4 in order. Selecting from users who are not logged in with IMAP4 is less likely to cause inconsistencies described in the following steps and loop.
[0033]
Subsequently, the following information is entered in the user information of the user selected in step S43. In other words, the user information of the selected user is copied to the mail data management server newly connected to the mail data of the mail data management server 5 that has been operating so far, and which mail data management server ( Information such as which mail data management server (new mail data management server) the mail data is being copied from the currently used mail data management server in operation is entered. This operation is performed for user information of all users.
Note that this information is used to confirm whether or not there is one server in step S12 in FIG.
[0034]
Next, after looking at the folder structure of the corresponding user, the folder information is copied to the new mail data management server 5 in units of folders (step S44).
Subsequently, it is checked whether the user has accessed the folder during copying of the folder (step S45).
A history is taken when processing is performed in response to the access request in step S14 of FIG. 2, but this can be determined from this history.
[0035]
If nothing has been changed in step S45, the process ends for the folder, and the process proceeds to the process shown in FIG.
On the other hand, if the user accesses the folder during folder copying in step S45, it is determined whether the access content being copied is, for example, the protocol of IMAP4 (step S46). Here, since inconsistency does not occur unless the protocol is IMAP4, the process proceeds to FIG. Although an example using the IMAP4 protocol has been described here, this is a protocol for changing the state on the mail data management server 5 (for example, changing the state such as deleting mail data or changing a flag). It is not necessarily limited to the IMAP4 protocol shown in the example here.
[0036]
If it is determined in step S46 that the protocol is IMAP4, the execution history is analyzed, the target folder and mail data to which changes are made are picked up, and a table is created (step S47).
[0037]
In accordance with this table, the new and old servers confirm whether or not the folder exists, and information on whether there is a mismatch is set in the table. For example, if there is subscription information in the IMAP4 protocol in this folder, the difference between the information is confirmed by the old and new servers, and information indicating whether there is a mismatch is set in the table.
According to this table, it is checked whether or not the mail data exists and whether status information such as a flag is changed, and information on whether or not there is a mismatch is set in the table.
[0038]
Next, looking at this table, if there is no inconsistency, the process proceeds to the process of FIG. 7 described later (step S48).
If there is inconsistency, copy the inconsistent information from the old mail data management server to the new mail data management server, eliminate the inconsistency, and access the user again during the investigation of the copy. In order to check whether there is any, the process moves to step S45, and the same processing is repeated (step S49).
Here, if the user always logs in with IMAP4 and keeps changing the state, there may theoretically be a case where this loop cannot be exited, but it may be considered that the user cannot continue to use it indefinitely.
[0039]
Next, the data copy end processing operation of the mail data management server 5 will be described with reference to FIG.
First, it is checked whether or not the copy processing described in FIG. 6 has been completed for all folders (step S51). Here, if all the folders have not been completed, the processing after step S44 in FIG. 6 is executed for the remaining folders in step S55.
On the other hand, if all the folders have been completed, the information of the mail data management server 5 stored in the user is restored, that is, the copy is returned to the normal state, and only the information of the mail data management server 5 is updated. The mail data management server 5 is changed, that is, the information of the mail data management server 5 in the user information is changed from the original old mail data management server to the new mail data management server (step S52).
[0040]
Next, it is investigated whether or not the execution has been completed for all users (step S53). If not completed, the processes after step S43 in FIG. 6 are executed for the remaining users in step S56. If execution has been completed for all users, the copy of the corresponding mail server is complete, so the old mail data management server 5 is disconnected (step S54), and the process is completed.
Note that this processing is executed by the same method when, for example, the mail system is operated by one mail server, but it is desired to distribute to two servers due to an increase in processing capacity.
Further, since the user information includes server name information to be accessed, the servers can be distributed.
[0041]
In this way, only the part of all the users in the copy process shown in FIG. 6 is performed for all the specified users, and only a part of the users are copied to the new mail data management server. Can be migrated to.
[0042]
As described above, according to the present embodiment, it is possible to perform upgrades of the mail server part, hardware replacement, switching to multiple servers due to insufficient capacity, etc. without stopping the service in a system operating as a mail system. effective.
Also, by not stopping the service, there is an effect that a large amount of processing is performed while the service is stopped, and it is possible to avoid the occurrence of a failure due to concentration of access to mail data immediately after the service is restarted.
[0043]
【effect】
Since the present invention is configured as described above, the following effects can be obtained.
[0044]
According to the present invention, a new mail data management server is connected to a network while a plurality of mail data management servers are in operation, and user mail data in the plurality of mail data management servers operating in the new mail data management server is received. By copying the information in folders and having the copied information in the front-end server and user authentication server, the mail server part (mail data management server) can be upgraded, the hardware can be replaced, and the capacity can be increased. There is an effect that switching to a plurality of mail servers due to shortage can be executed without stopping the service.
Also, by not stopping the service, there is an effect that a large amount of processing is performed while the service is stopped, and it is possible to avoid the occurrence of a failure due to concentration of access to mail data immediately after the service is restarted.
[Brief description of the drawings]
FIG. 1 is a configuration diagram of an electronic mail system according to a first embodiment.
FIG. 2 is a flowchart showing an operation procedure of the electronic mail system according to the first embodiment.
FIG. 3 is a flowchart showing an operation procedure during server distribution according to the first embodiment.
4 is a flowchart showing a procedure for requesting a plurality of mail data management servers 5 according to Embodiment 1. FIG.
FIG. 5 is a flowchart showing an operation procedure for combining response results of a plurality of mail data management servers 5 according to the first embodiment.
FIG. 6 is a flowchart showing a data copy operation procedure of the mail data management server 5 according to the first embodiment.
7 is a flowchart showing an operation procedure of a data copy end process of the mail data management server 5 according to the first embodiment. FIG.
[Explanation of symbols]
1 Internet or Intranet 2 Front-end server 3 User authentication server 4 User database 5 Mail data management server 6 Network 11 Access monitoring unit 12 User authentication unit 13 User DB management unit 14 Command analysis unit 15 Mail server access management unit, 16 A plurality of mail data management units.

Claims (5)

A plurality of mail data management servers that execute processing based on access requests from users transmitted via the network and manage mail data for each user,
Information of a mail data management server that stores user information of the user and manages user mail data corresponding to the user information when the user information transmitted from the user exists in the stored user information A user authentication server to obtain
Connected to the plurality of mail data management servers via a network, acquires the access contents transmitted from the user, and acquires the access contents acquired and the information of the mail data management server acquired by the user authentication server. In an e-mail system including a front-end server that identifies a mail data management server to be accessed based on and returns a processing result executed by the identified mail data management server to the user,
The front-end server connects a new mail data management server to the network during operation of the plurality of mail data management servers, and the users in the plurality of mail data management servers operating on the new mail data management server. The mail data is copied, the information that the new mail data management server is connected is added to the management table held by itself, and the plurality of mail data that are operating on the new mail data management server are added to the user information. An e-mail system comprising a mail server access management unit for adding information obtained by copying user mail data in a server.   When all of the user's mail data has been copied, the mail server access management unit returns the mail data management server information stored in the user to the normal state before copying, and the mail data in the user information 2. The electronic mail system according to claim 1, wherein the information on the management server is changed to information on a new mail data management server.   The mail server access management unit determines whether there is one piece of mail data management server information acquired by the user authentication server, and when there are a plurality of pieces of mail data management server information, 2. The electronic device according to claim 1, wherein the electronic mail management server accesses the data management server, synthesizes the processing results executed by the plurality of mail data management servers in accordance with the access request, collects the history of access contents, and returns the result to the user. Mail system. The mail server access management unit includes a folder name corresponding to the user's mail data based on the processing result executed by the specific mail data management server, and unique ID information and data in the folder. One correspondence table is created for each mail data management server, data of the same folder name and the same ID information is retrieved from the plurality of first correspondence tables created, and the same folder as the retrieved identical data The above processing result is synthesized by creating a second correspondence table composed of folder names, ID information, and data in which names do not overlap with the same ID information and each information does not contradict each other. The e-mail system according to claim 3 .   2. The electronic mail system according to claim 1, wherein the mail server access management unit determines a protocol of an access request from a user and specifies a mail data management server based on the protocol.

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