JP6035601B2 - Packet replay method - Google Patents

Description

  The present invention relates to a computer system that reproduces communication between a plurality of nodes. In particular, it relates to reproduction using packet capture. The present invention can also be applied to analysis of failures or the like due to reproduced communication and analysis during migration.

  In a computer system composed of a plurality of nodes and in which processing is performed in cooperation with each node, there are cases where it is desired to process (reproduce) the contents previously processed by the computer system again. Two examples are given below.

  The first is a case where a problem that has occurred in a certain computer node is to be reproduced. If the computer system behaves unexpectedly due to factors such as bugs, the purpose is to check for problems and test after correction. In this example, the processing period is short and the processing content is small.

  The second is a case where when a successor node of a certain computer node is developed, it is confirmed whether the same processing as before is performed. In this example, the processing period is long and the processing content is large.

  In this reprocessing, despite the fact that there are only one or a few computer nodes, the same processing must be executed in the entire computer system for reprocessing, which is expensive. is there. In particular, when the computer system to be reprocessed is currently operating a service, the service must be stopped for reprocessing, which greatly affects the quality of the service.

  The technique used there is a packet replay technique. In the replay, first, a communication packet exchanged between computer nodes in a computer system is captured and recorded in advance. When reprocessing is performed on a certain computer node, only a target computer node (target node) and a computer node (replay node) that performs replay are prepared. The replay node simulates a plurality of computer nodes, and transmits the packet received by the target node among the recorded communication packets, thereby reproducing the same communication as at the time of capture.

  In general replay, the replay at the same time interval as when it was recorded is realized by associating and recording the time when the communication packet was transmitted and the communication packet.

  Patent Document 1 describes a method of recording a received packet amount at the time of each packet transmission of each computer node when recording a communication packet. The transmission condition of each packet when performing replay uses the above-described received packet amount in addition to the above-described time information. By transmitting a packet when the two conditions are satisfied, replay can be performed as if a pseudo response is being made.

  Patent Document 2 describes a method in which a request (request) and a response (response) in communication between nodes are paired, and if a target node transmits a request, the replay node transmits the response. Although it is assumed that a request and a response are related, a reliable replay of the response is possible.

JP 2010-205011 A JP 2008-97457 A

  In replay, it is desirable that the packet is accurate when it is desired to capture. This accuracy includes not only the time of capture but also the interval between requests and responses made between nodes. This is because, for example, node B is simulated in a process in which node B receives a packet transmitted by node A, performs processing inside node B, and transmits the result to node A. At this time, when replaying is based only on time information, when node A transmits a packet delayed due to some factor, in the worst case, a node simulating node B transmits a packet before transmitting node A. End up. This is an inappropriate replay because the response is returned before the request is received.

  In order to solve the above problems, the present invention reproduces the processing time of the node that has received the request in communication, and prepares a plurality of replay patterns to capture the captured packet and the captured packet. One pattern is specified from a plurality of replay patterns according to the relationship with time, and reproduction processing is executed according to the contents.

A more specific form is as follows.
A packet replay device using a device for calculating a relationship between packets, wherein the packet replay device uses a device having a function of copying and transferring a packet on a network path, and duplicating a packet exchanged The capture packet is input, the capture packet is associated with the capture time, the packet relationship that is the relationship between the capture packets is calculated based on the packet relationship calculation rule, the pattern is selected from the five replay patterns, and the replay target node On the other hand, based on a transmission packet creation rule, a replay transmission packet is created from the capture packet, the replay transmission packet is transmitted at a timing based on the replay pattern, and a reception packet is obtained from the replay target node via the network. The time, based on a comparison rule, to compare the contents of the received packet and the capture packet, if the replay transmission packet to respond is present for transmission.

  According to the exemplary embodiment of the present invention, it is possible to simulate a response to a request and simulate an application processing delay in packet replay.

The block diagram of the packet replay apparatus which performs packet relationship analysis and replay in one embodiment of this invention System configuration diagram when using packet replay device in one embodiment of the present invention Flow of packet replay analysis processing in one embodiment of the present invention Flow of packet replay relationship analysis processing in one embodiment of the present invention The figure which shows the additional information passed to the packet transmission part in one embodiment of this invention The figure which shows the additional information passed to the packet receiving part in one embodiment of this invention Flow of packet replay transmission request processing in an embodiment of the present invention Flow of packet replay transmission processing in one embodiment of the present invention Packet replay reception processing flow in one embodiment of the present invention The figure which shows the conversion information at the time of communication in one embodiment of this invention

A typical embodiment of the present invention is a computer system having a packet transmission / reception function.
The packet replay function accepts the capture packet, the packet relation calculation rule, the packet generation rule, and the packet comparison rule from the outside, selects the optimum replay method in packet replay, and the replay target node A replay transmission packet is transmitted.

  In a typical embodiment of the present invention, packet replay techniques are classified into five types: scheduled replay, continuous replay, time difference continuous replay, response replay, and time difference response replay.

  Scheduled replay performs replay based on the elapsed time at the time of packet capture, continuous replay and time difference continuous replay perform replay triggered by transmission of the replay packet, and response replay and time difference response replay receive packets from the target node. Replay when triggered.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1A is a block diagram of a packet replay device 101 that performs packet relationship analysis and replay according to the embodiment. Each of the following devices is realized by a so-called information processing device, and a calculation unit (CPU) executes processing shown below according to a program.

  The packet replay device 101 is a device for receiving packet information exchanged in a computer system and replaying packet information by simulating an arbitrary number of nodes in the computer system.

  The packet replay device 101 includes a packet replay unit 102, a network interface 103 as a general computer resource, a memory 104, a CPU 105, a storage device 106, and a user interface 107.

  Of the information input from the user interface 107 by the user, the packet information is sent to the packet information receiving unit 108, the computer node information to be simulated and the interpacket relationship calculation rule are sent to the interpacket relationship calculation unit 109, and the packet transmission rule Is sent to the packet transmission setting unit 110, the packet comparison rule is sent to the packet comparison unit 111, and the communication conversion information is sent to the communication information conversion unit. These pieces of information are stored in the storage device 106 in the form of various queues and tables.

The packet replay device 101 further includes a packet information analysis unit 112, a packet transmission unit 113,
A packet receiving unit 114 and a replay result output unit 115 are provided.
Each unit (each function) of the packet replay unit 102 is realized by executing a predetermined computer program recorded in the memory on a computer resource.

  FIG. 1B is a system configuration diagram when the packet replay device is used. In the packet collection environment 120, the computer nodes 121 communicate with each other via a network 123. The packet collection device is installed between the computer node 121 and the network 123, acquires the content of communication, and sends it to the packet replay device 101 as packet information 124. In the packet replay environment 125, the packet replay device 101 performs communication simulating the computer node 121 based on the packet information 124 (FIG. 1: 126).

  FIG. 2A is a flow of packet replay analysis processing. The packet information analysis unit 112 analyzes the packet information, divides the packet information into information for each protocol and communication layer, and creates packet analysis information given a packet identifier as an identifier.

The inter-packet relationship calculation unit 109 receives the packet analysis information from the packet information analysis unit 112, and calculates the replay pattern of the packet analysis information using the inter-packet relationship calculation rule that has been input in advance. In the replay, for the packet that needs to be transmitted from the packet replay device 101, the packet analysis information, the replay pattern, and the transmission supplement information are registered together in the packet transmission unit 113. At this time, if the replay pattern of the registered packet is a scheduled replay (FIG. 2A: 201), the packet is set as a timer waiting state (FIG. 2A: 202).
In the replay, the packet received by the packet replay device 101 is registered in the packet receiving unit 114 together with the packet analysis information and the reception supplement information.

FIG. 2B is a flow of packet replay relationship analysis processing.
The interpacket relationship calculation unit 109 calculates a replay pattern used when replaying packet analysis information. In the inter-packet relationship analysis processing, a loop is used for a packet to be compared (FIG. 2B: 210), and processing is performed for each comparison packet. A loop is performed for each given relationship (FIG. 2B: 212) (FIG. 2B: 211), the input packet and the comparison packet are applied to each relationship rule (FIG. 2B: 213), and the relationship is calculated. In this case (FIG. 2B: 214), the replay pattern of the input packet and supplementary information for replay are given (FIG. 2B: 215) (FIG. 3: 303) (FIG. 4: 402). If there is no relationship with any packet, the replay pattern is set to “regular” (FIG. 2B: 216).

  The packets to be compared are basically all packet analysis information obtained before the start of each analysis, but the target may be narrowed down using time and address information.

  FIG. 3 shows information given in addition to the packet analysis information when the analysis information is passed to the packet transmission unit 113. The packet identifier 301 is information included in the packet analysis information, and is used when representing a connection between packets. The replay pattern 302 is obtained by classifying packet transmission methods by replay into five types. The transmission supplement information 303 describes supplement information necessary for replay.

  FIG. 4 shows information given in addition to the packet analysis information when the analysis information is passed to the packet receiving unit 114. The packet identifier 401 is information included in the packet analysis information, and is used when representing a connection between packets. The supplementary information 402 for receiving describes supplementary information necessary for replaying a response when receiving a packet.

FIG. 5 is a flow of packet replay transmission request processing.
Transmission processing is performed using a loop for transmission packets waiting for a timer at regular intervals (FIG. 5: 501). When the packet waiting time has elapsed (FIG. 5: 502), the target packet is placed in the transmission queue (FIG. 5: 503). When there is a continuous transmission packet following the transmitted packet (FIG. 5: 504), the packet is set in a timer waiting state (FIG. 5: 505). The waiting time is set to zero so that transmission is performed immediately. When there is a time difference continuous transmission packet following the transmitted packet (FIG. 5: 506), the packet is set in a timer waiting state (FIG. 5: 507). The timer waiting time is given as transmission supplementary information 303 from the inter-packet relationship calculation unit 109 at the time of analysis.

  FIG. 6 is a flow of packet replay transmission processing. This process is performed every time a transmission packet is placed in the transmission queue. After the transmission packet (FIG. 6: 601) is taken out from the transmission queue, it is checked whether a transmission rule is set in the replay system (FIG. 6: 602). If it is set, the packet is transmitted after shaping the transmission packet (FIG. 6: 604) based on the transmission rule (FIG. 6: 603) (FIG. 6: 605).

FIG. 7 is a flow of packet replay reception processing. When receiving a packet from an external node, the reception process is performed using a loop for the transmission packet waiting to be received (Figure: 701)
. Using the comparison rule (FIG. 7: 702), the received packet is compared with each reception waiting packet (FIG. 7: 703). If the two packets match (FIG. 7: 704), it is checked whether a response is necessary. When the packet waiting for reception performs packet replay as a response (FIG. 7: 705), the target transmission packet is set to the timer waiting state (FIG. 7: 706). The waiting time is set to zero so that transmission is performed immediately. When there is a time difference response transmission packet (FIG. 7: 707), the packet is set to a timer waiting state (FIG. 7: 708). The timer waiting time is given as transmission supplementary information 303 from the inter-packet relationship calculation unit 109 at the time of analysis.

  Note that the number of objects of the loop target packet analysis information may be narrowed down by using time or a communication path.

  FIG. 8 shows communication conversion information. In the communication conversion information 801, a parameter 803 conversion rule for each protocol 802 is described. When transmitting and receiving a packet, the conversion source information 804 is referred to. When the communication information to be used corresponds to the conversion source information 804, the conversion to the conversion destination information 805 is performed before transmission / reception processing is performed.

  In the present embodiment, a packet relationship rule that matches the configuration of the computer system is created, and the packet relationship is calculated by applying the rule to the captured packet. This realizes not only the improvement of replay work efficiency but also capture and replay that do not affect the capture target system.

  Since the partial job pattern creation method of the present invention shows the cost for each partial job pattern and the amount of computer resources that can be migrated in migration, the user can select the optimum partial job pattern in consideration of cost effectiveness. it can.

101 packet replay device
102 Packet replay section
103 Network interface
104 memory
105 CPU
106 Storage device
107 User interface
108 Packet information reception part
109 Interpacket relationship calculator
110 Packet transmission setting section
111 Packet comparator
112 Packet information analyzer
113 Packet transmitter
114 Packet receiver
115 Replay result output section
116 Communication conversion information reception part

Claims (10)

A packet replay method using packet relationship analysis,
A plurality of replay patterns are stored in advance,
Capture packets sent and received between nodes,
A capture start time that is a time when capture is started is stored , a capture packet that is the captured packet, a packet analysis result that is an analysis result of the capture packet , and a capture completion time that is a time when the capture packet is captured Are stored in association with each other.
Based on the associated information, a predetermined replay pattern is specified from the plurality of replay patterns,
A packet replay method, wherein reproduction processing is executed using an identified replay pattern. The packet replay method according to claim 1,
The plurality of replay patterns include scheduled replay, continuous replay, time difference continuous replay,
Response replay and time difference response replay,
The reproduction process transmits a replay transmission packet created from the identified replay pattern and the capture packet to a replay target node at a timing based on the identified replay pattern, and received from the replay target node. A packet replay method comprising: determining whether a packet is reproduced by comparing the captured packet. The packet replay method according to claim 2, wherein
The scheduled replay does not receive a related packet related to the capture packet, and transmits the replay transmission packet when a capture time that is a difference between the capture start time and the capture completion time has elapsed since the start of replay. And a packet replay method. The packet replay method according to claim 2, wherein
In the continuous replay, the replay transmission packet is transmitted within a predetermined time after the related packet related to the capture packet is transmitted. The packet replay method according to claim 2, wherein
In the time difference continuous replay, after the related packet related to the capture packet is transmitted, the replay transmission packet is transmitted after the time difference continuous replay time elapses, and the time difference continuous replay time includes the capture packet and the related packet, respectively A packet replay method using a capture time difference that is a difference between the capture start time and the capture completion time. The packet replay method according to claim 2, wherein
In the packet replay method, the response replay transmits the replay transmission packet within a predetermined time after receiving a related packet related to the capture packet. The packet replay method according to claim 2, wherein
After receiving the related packet related to the capture packet, the replay transmission packet is transmitted after the time difference response replay time elapses, and the time difference response replay time is determined by the capture start time of each of the capture packet and the related packet and the capture packet. A packet replay method characterized by using a difference in capture time that is a difference from a capture completion time. The packet replay method according to any one of claims 2 to 7,
The replay pattern is identified by arbitrarily combining header information and payload information of the capture packet, the packet analysis result, the capture completion time, and a capture time that is a difference between the capture start time and the capture completion time. A packet replay method which is executed based on a relation calculation rule. The packet replay method according to any one of claims 2 to 8,
The packet replay method, wherein the replay transmission packet is generated when the replay transmission packet is transmitted. The packet replay method according to any one of claims 2 to 8,
A packet replay method, comprising: a packet comparison rule that serves as a determination criterion when comparing the captured packet and the received packet, and performing the reproduction determination according to the packet comparison rule.

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