Server, processing system, processing method, and program

Abstract

To provide a server capable of shortening the time required to start life-and-death monitoring, even if part of the life-and-death monitoring frames are lost.SOLUTION: The server includes a control mechanism that, in life-and-death monitoring, transmits a second life-and-death monitoring frame to another server before receiving the first of multiple first life-and-death monitoring frames sent from the other server different from an own server, and determines whether the network is down on the basis of the multiple first life-and-death monitoring frames.SELECTED DRAWING: Figure 13

Description

[Technical Field]

[0001] The present disclosure relates to a server, a processing system, a processing method, and a program. [Background technology]

[0002] Systems in which servers communicate with each other are used in a variety of fields. Patent Document 1 discloses a related technology for determining whether an abnormality in the operation of a virtualized system is due to an abnormality in an application or virtual machine, or an abnormality on the network side. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-007609 Summary of the Invention [Problem to be solved by the invention]

[0004] In the system related to Patent Document 1, health monitoring does not start until a User Datagram Protocol (UDP) packet for health monitoring is received, and if the UDP packet is lost, it takes time for health monitoring to start. Therefore, there is a need for technology that can shorten the time until health monitoring starts even if some health monitoring frames are lost.

[0005] One of the objectives of each aspect of the present disclosure is to provide a server, a processing system, a processing method, and a program that can solve the above-mentioned problems. [Means for solving the problem]

[0006] In order to achieve the above object, according to one aspect of the present disclosure, a server is provided with a control mechanism that, in health monitoring, before receiving the first of a plurality of first health monitoring frames, which are health monitoring frames transmitted from a server other than the server itself, transmits a second health monitoring frame, which is a health monitoring frame, to the other server, and determines whether the network is down based on the plurality of first health monitoring frames.

[0007] To achieve the above object, according to another aspect of the present disclosure, a processing system includes the above server and another server separate from the server.

[0008] In order to achieve the above object, according to another aspect of the present disclosure, the processing method includes determining that the network is not down even if some of the health check frames are lost, if the next health check frame is received before the count value exceeds a certain value.

[0009] In order to achieve the above object, according to another aspect of the present disclosure, a program causes a computer to perform health monitoring by sending a second health monitoring frame to a server other than the server before receiving the first of multiple first health monitoring frames, which are health monitoring frames transmitted from the server other than the server itself, and determining whether the network is down based on the multiple first health monitoring frames. [Effects of the Invention]

[0010] According to each aspect of the present disclosure, even if some of the health check frames are lost, it is possible to shorten the time until health check starts. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 illustrates an example of a configuration of a processing system according to some embodiments of the present disclosure. [Figure 2]FIG. 10 is a diagram illustrating an example of the functions of a control mechanism according to some embodiments of the present disclosure. [Figure 3] FIG. 1 is a diagram illustrating an example of a processing flow of a processing system according to some embodiments of the present disclosure. [Figure 4] FIG. 2 is a diagram illustrating a first process performed by a processing system according to some embodiments of the present disclosure. [Figure 5] 10A and 10B are diagrams for explaining second and third processes performed by a processing system according to some embodiments of the present disclosure. [Figure 6] FIG. 2 is a first diagram illustrating transmission of a health check frame according to some embodiments of the present disclosure. [Figure 7] FIG. 10 is a second diagram illustrating transmission of health check frames according to some embodiments of the present disclosure. [Figure 8] FIG. 10 is a diagram for explaining a fourth process performed by a processing system according to some embodiments of the present disclosure. [Figure 9] FIG. 10 is a diagram for explaining a fifth process performed by a processing system according to some embodiments of the present disclosure. [Figure 10] FIG. 10 is a diagram for explaining a sixth process performed by a processing system according to some embodiments of the present disclosure. [Figure 11] FIG. 10 illustrates an example of a state of determination performed by a processing system according to some embodiments of the present disclosure. [Figure 12] FIG. 10 illustrates an example of a function being stopped by a server according to some embodiments of the present disclosure. [Figure 13] FIG. 10 is a diagram illustrating an example of a processing flow of a server according to some embodiments of the present disclosure. [Figure 14] FIG. 10 is a diagram illustrating an example of a processing flow of a server according to some embodiments of the present disclosure. [Figure 15] FIG. 1 is a schematic block diagram illustrating the configuration of a computer according to at least one embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, the embodiments will be described in detail with reference to the drawings. <Embodiment> A processing system 1 according to an embodiment of the present disclosure will be described with reference to the drawings. The processing system 1 is a system that monitors whether a network between server devices 10a and 10b (described later) is down and quickly detects any downtime. This makes it possible to reduce the impact on communication by users using the server devices 10a and 10b. Furthermore, the processing system 1 allows users to disable or stop monitoring the network for downtime at their discretion.

[0013] (Configuration of the processing system of the present disclosure) FIG. 1 is a diagram illustrating an example of a configuration of a processing system 1 according to some embodiments of the present disclosure. As shown in FIG. 1, the processing system 1 according to one embodiment of the present disclosure includes servers 10a and 10b, a communication device 20, and cables 30a and 30b. As shown in FIG. 1, the server 10a is connected to the communication device 20 via the cable 30a. As shown in FIG. 1, the server 10b is connected to the communication device 20 via the cable 30b. The servers 10a and 10b may be collectively referred to as servers 10. The cables 30a and 30b may be collectively referred to as cables 30. The cables 30 may be, for example, a LAN (Local Area Network) cable.

[0014] Each of the servers 10 includes a network device 101. The network device 101 includes a NIC (Network Interface Card) 1011, a NIC driver 1012, and a control mechanism 1013, as shown in FIG.

[0015] The NIC 1011 is a card-type expansion device for connecting the server 10 including the NIC 1011 itself to a communication network (for example, a local area network).

[0016] The NIC driver 1012 is a program that mediates communication between the NIC 1011 and the OS (Operating System) in the network device 101 that includes the NIC driver 1012 itself. The NIC driver 1012 runs within the network device 101 that includes the NIC driver 1012 itself.

[0017] The control mechanism 1013 is firmware for the network device 101 provided in each server 10. The control mechanism 1013 runs an alive monitoring program in each network device 101. FIG. 2 is a diagram illustrating an example of functions possessed by the control mechanism 1013 according to some embodiments of the present disclosure. As shown in FIG. 2, the control mechanism 1013 has a frame transmission / reception function 1013a, a counter function 1013b, a timer function 1013c, and an alive monitoring flag setting function 1013d.

[0018] The frame sending / receiving function 1013a is a function for sending and receiving health check frames, which are frames used for health checks. Health check frames include User Datagram Protocol (UDP) packets for health checks. The counter function 1013b is a function for counting the number of health check frames received and checking the count value and incrementing the count. The timer function 1013c is a function for measuring the passage of time. The health check flag setting function 1013d is a function for setting the enable / disable of health checks. Health checks involve continuously checking the operating status of devices such as servers and the software running on those devices.

[0019] The control mechanism 1013 transmits and receives health monitoring frames using a frame transmission / reception function 1013a and a socket API (Application Programming Interface) 1013a5. The socket API 1013a5 is a set of socket calls that enable various communication functions to be executed between application programs. For example, the socket API 1013a5 includes socket calls for setting up and establishing connections with other users (processes) on the network, and socket calls for transmitting and receiving data to and from other users (processes).

[0020] The control mechanism 1013 also uses a counter function 1013b to count up and check the count value at regular intervals T. The control mechanism 1013 uses a timer function 1013c to repeatedly measure, for example, the passage of a certain period of time T. The control mechanism 1013 uses a health check flag setting function 1013d to perform settings for controlling whether health checks set by the OS or upper level applications are enabled or disabled.

[0021] The communication device 20 is, for example, a router connected to a communication network, or a hub connected to a router.

[0022] Cable 30a connects server 10a and communication device 20. This connection connects server 10a to the communication network. Cable 30b connects server 10b and communication device 20. This connection connects server 10b to the communication network. In this way, by connecting server 10a to communication device 20 and by connecting server 10b to communication device 20, server 10a and server 10b become able to communicate with each other via the communication network.

[0023] The above-described processing performed by the processing system 1 according to the embodiment of the present disclosure is merely an example, and the processing system 1 is not limited to the above-described processing. For example, the processing system 1 may perform the processing described below.

[0024] (Processing performed by the processing system of the present disclosure) Fig. 3 is a diagram illustrating an example of a processing flow of the processing system 1 according to some embodiments of the present disclosure. Here, a description will be given of processing performed by the processing system 1 illustrated in Fig. 3. Note that here, a description will be given of processing for alive monitoring when communication is performed between the control mechanism 1013 of the server 10a and the control mechanism 1013 of the server 10b.

[0025] In the network device 101 of the server 10, the control mechanism 1013 runs an alive-or-dead monitoring program. FIG. 4 is a diagram illustrating a first process performed by the processing system 1 according to some embodiments of the present disclosure. The first process is, for example, the process of step S1 performed by the processing system 1. The control mechanism 1013 of the server 10 enables the alive-or-dead monitoring flag setting function 1013d, and establishes a connection with the control mechanism 1013 of the other server 10 by a handshake with the network device 101 using the alive-or-dead monitoring flag setting function 1013d to enable the alive-or-dead monitoring flag (step S1).

[0026] Specifically, for example, in the processing system 1, the control mechanism 1013 of the server 10a activates the alive-check flag. Then, the control mechanism 1013 of the server 10a transmits a connection frame to the server 10b. The connection frame is a frame including a UDP packet for establishing a connection. The data portion of the UDP packet has a data format that allows the control mechanism to recognize it as a connection request. This transmission is performed before the control mechanism 1013 of the server 10b receives the alive-check frame from the server 10a. The control mechanism 1013 of the server 10b receives the connection frame from the server 10a. Upon receiving the connection frame, the control mechanism 1013 of the server 10b transmits a response frame to the server 10a in response to the reception of the connection frame. The control mechanism 1013 of the server 10a receives the response frame from the server 10b. Upon receiving the response frame from the server 10b, the control mechanism 1013 of the server 10a transitions to a connection-established state in response to the reception of the response frame. Also, in the processing system 1, the control mechanism 1013 of the server 10b activates the alive-check flag. Then, the control mechanism 1013 of server 10b transmits the health check frame to server 10a. This transmission is performed before the control mechanism 1013 of server 10a receives the health check frame from server 10b. The control mechanism 1013 of server 10a receives the health check frame from server 10b. Upon receiving the received health check frame, the control mechanism 1013 of server 10a transmits a response frame to server 10b in response to the reception. The control mechanism 1013 of server 10b receives the response frame from server 10a. Upon receiving the response frame from server 10a, the control mechanism 1013 of server 10b transitions to a connection established state in response to the reception.

[0027] FIG. 5 is a diagram illustrating second and third processes performed by the processing system 1 according to some embodiments of the present disclosure. The second process is, for example, the process of step S2 performed by the processing system 1. The third process is, for example, the process of step S3 performed by the processing system 1. The control mechanism 1013 of the server 10 enables the counter function 1013b and the timer function 1013c (step S2). Then, the control mechanism 1013 of the server 10 starts a transmission check and a reception check of the UDP alive-check frame when the frame transmission / reception function 1013a transmits and receives the alive-check frame (step S3). For example, the transmission check is performed by confirming whether the frame transmission process has been completed successfully. For example, the reception check is performed by reading the data portion of the received frame and confirming whether the alive-check frame has been received. The transmission of the alive-check frame is performed periodically at a fixed interval T using the timer function 1013c.

[0028] Note that the transmission of health check frames does not have to be periodically performed at a fixed interval T. FIG. 6 is a first diagram illustrating the transmission of health check frames according to some embodiments of the present disclosure. FIG. 7 is a second diagram illustrating the transmission of health check frames according to some embodiments of the present disclosure. For example, as shown in FIG. 6, the fixed interval T may be calculated from the arrival time t of the health check frame when establishing a connection (i.e., during handshake). The fixed interval T is assumed to be a value that includes a margin in the arrival time t, and is set to, for example, t × 1.2. Furthermore, for example, the transmission interval of the second and subsequent health check frames may be varied based on statistical information on the transmission interval of the health check frame and the line usage rate, as shown in FIG. 7. Specifically, as shown in parts (a) and (b) of FIG. 7, the statistical information on the transmission interval of the health check frame and the line usage rate are acquired using well-known techniques. As shown in part (b) of Figure 7, when the line utilization rate exceeds a certain value, the transmission interval of the health check frames may be lengthened to reduce the impact on traffic, and when the line utilization rate is below a certain value, the transmission interval of the health check frames may be shortened to shorten the time it takes to detect a network downtime. In the specific example shown in part (b) of Figure 7, when the line utilization rate is 80% or higher, the transmission interval of the health check frames is set to twice the transmission interval of the previous health check frames. When the line utilization rate is 40% or higher but less than 80%, the transmission interval of the health check frames is set to the transmission interval of the previous health check frames. When the line utilization rate is 0% or higher but less than 40%, the transmission interval of the health check frames is set to half the transmission interval of the previous health check frames.

[0029] It is also possible to set an upper limit to the transmission interval of the health check frame. Setting an upper limit to the transmission interval of the health check frame has the effect of preventing the time required to discover a network downtime from becoming excessively long.

[0030] 8 is a diagram illustrating a fourth process performed by the processing system 1 according to some embodiments of the present disclosure. The fourth process is, for example, the process of step S4 performed by the processing system 1. The control mechanism 1013 of the server 10 uses the counter function 1013b to count up and check the count value at regular intervals T (step S4).

[0031] 9 is a diagram illustrating a fifth process performed by the processing system 1 according to some embodiments of the present disclosure. The fifth process is, for example, the process of step S5 performed by the processing system 1. Upon receiving the health check frame, the control mechanism 1013 of the server 10 resets the counter function 1013b (step S5).

[0032] 10 is a diagram illustrating a sixth process performed by the processing system 1 according to some embodiments of the present disclosure. The sixth process is, for example, the process of step S6 performed by the processing system 1. When the count value exceeds a certain value, the control mechanism 1013 of the server 10 determines that the network is down (step S6).

[0033] Note that even if some of the health check frames are lost, the control mechanism 1013 of the server 10 determines that the network is not down as long as the next health check frame is received before the count value exceeds a certain value. FIG. 11 is a diagram illustrating an example of a state of determination made by the processing system 1 according to some embodiments of the present disclosure. Specifically, it is a diagram illustrating a state in which the processing system 1 determines that the network is not down even if some of the health check frames are lost. As illustrated in FIG. 11, in the processing system 1, the control mechanism 1013 of the server 10 receives the next health check frame before the count value exceeds a certain value. In this case, the control mechanism 1013 of the server 10 determines that the network is not down even if some of the health check frames are lost.

[0034] Furthermore, when an enabled health check flag is cleared or the network device 101 transitions to a disconnected state through a handshake, the server 10 stops the frame transmission / reception function 1013a, the counter function 1013b, and the timer function 1013c, which perform transmission and reception checks of health check frames. Figure 12 is a diagram showing an example of the suspension of functions performed by the server 10 according to some embodiments of the present disclosure. In the example shown in Figure 12, when the network device 101 transitions to a disconnected state through a handshake, the server 10 stops the frame transmission / reception function 1013a, the counter function 1013b, and the timer function 1013c.

[0035] (advantage) The processing system 1 according to an embodiment of the present disclosure has been described above. In the processing system 1, the server 10 includes a control mechanism 1013 that, in health checks, transmits a second health check frame, which is a health check frame, to another server 10 before receiving the first of multiple first health check frames, which are health check frames transmitted from the other server 10, and determines whether the network is down based on the multiple first health check frames.

[0036] The invention described in Patent Document 1 transmits a health check UDP packet in response to a received health check UDP packet. In other words, with the invention described in Patent Document 1, health check does not start until the health check UDP packet is received, and if the health check UDP packet is lost, it takes time to start health check. In contrast to the invention described in Patent Document 1, server 10 can shorten the time until health check starts even if some of the health check frames are lost.

[0037] Furthermore, even if some of the multiple first health monitoring frames are lost, the control mechanism 1013 determines that the network is not down if it receives the next first health monitoring frame before the count value of the received first health monitoring frame among the multiple first health monitoring frames exceeds a certain value.

[0038] The invention described in Patent Document 1 compares the number of transmitted UDP packets with the number of returned UDP packets, and if the two numbers are the same, determines that there is no network failure. In the invention described in Patent Document 1, UDP is a connectionless protocol, and the invention described in Patent Document 1 may erroneously diagnose a network failure if return UDP packets cannot be received due to a momentary network outage or the like. In contrast to the invention described in Patent Document 1, the control mechanism 1013 in the server 10 can determine that the network is not down and receive new health-check frames even if some of the health-check frames are lost, thereby reducing the possibility that the server 10 will diagnose the network as down even if some of the health-check frames are lost due to a momentary network outage or the like.

[0039] The control mechanism 1013 may limit the number of packets in the health check frame to a predetermined number based on the load during health check. For example, by controlling the transmission (start / stop / transmission interval) of health check frames according to the state (i.e., load) of the network device 101 included in the server 10, traffic can be made appropriate and an increase in traffic can be suppressed. On the other hand, the invention described in Patent Document 1 limits the number of transmitted UDP packets to a predetermined number, but does not make the predetermined number appropriate for traffic according to the load. Note that the health check frame includes UDP packets. Therefore, if the number of health check frames is considered synonymous with the number of UDP packets, limiting the number of health check frames can be considered to limit the number of packets.

[0040] Furthermore, by providing the server 10 with the control mechanism 1013, it is possible for the servers 10 to monitor each other's status. In contrast, in the comparative invention (for example, the invention described in the patent document JP 2007-312091 A), a protocol is used in which packets are sent and received between routers, and it is not possible to monitor the status between servers.

[0041] In another embodiment of the present disclosure, the processing system 1 may include three or more servers 10. In the processing system 1, each server 10 may communicate with two or more servers 10 other than the server 10 itself in the same manner as the server 10 of the embodiment of the present disclosure.

[0042] In another embodiment of the present disclosure, the processing system 1 may notify a higher-level application or an OS (Operating System) via the control mechanism 1013 when the network goes down.

[0043] In another embodiment of the present disclosure, the network device 101 is not limited to being provided in the server 10, but may be a network device that operates independently, such as a router. The network device may have a control mechanism 1013.

[0044] 13 is a diagram illustrating an example of a processing flow of the server 300 according to some embodiments of the present disclosure. Next, processing of the server 300 according to some embodiments of the present disclosure will be described with reference to FIG.

[0045] Server 300 includes control mechanism 301. In the health check, before receiving the first of a plurality of first health check frames transmitted from a server other than its own server, control mechanism 301 transmits a second health check frame to the other server, and determines whether the network is down based on the plurality of first health check frames.

[0046] The control mechanism 301 can be realized, for example, by using the functions of the control mechanism 1013 illustrated in Figures 1 and 2. The server 300 can be realized, for example, by using the functions of the servers 10a and 10b illustrated in Figure 1.

[0047] Next, a description will be given of processing performed by the server 300 according to some embodiments of the present disclosure. Fig. 14 is a diagram showing an example of a processing flow of the server 300 according to some embodiments of the present disclosure. Here, the processing of the server 300 will be described with reference to Fig. 14.

[0048] In server 300, before receiving the first of a plurality of first health monitoring frames, which are health monitoring frames transmitted from a server other than the server itself, the control mechanism 301 transmits a second health monitoring frame, which is a health monitoring frame, to the other server in health monitoring, and determines whether the network is down or not based on the plurality of first health monitoring frames (step S101).

[0049] The above describes the server 300 according to some embodiments of the present disclosure. This server 300 can shorten the time until health check starts even if some of the health check frames are lost.

[0050] The order of the processes in each embodiment of the present disclosure may be changed as long as the processes are performed appropriately.

[0051] Each embodiment of the present disclosure has been described, but the processing system 1, server 10, and other control devices may have a computer system built therein. The above-described processing steps are stored in the form of a program on a computer-readable recording medium, and the computer reads and executes this program to perform the above processing. Specific examples of computers are shown below.

[0052] 15 is a schematic block diagram showing the configuration of a computer according to at least one embodiment. As shown in FIG. 15, the computer 5 includes a CPU (Central Processing Unit) 6, a main memory 7, a storage 8, and an interface 9.

[0053] For example, the processing system 1, server 10, and other control devices described above are each implemented in a computer 5. The operations of each of the processing units described above are stored in the form of a program in a storage 8. A CPU 6 reads the program from the storage 8, loads it into a main memory 7, and executes the above-described processing in accordance with the program. The CPU 6 also allocates storage areas in the main memory 7 corresponding to each of the storage units described above in accordance with the program.

[0054] Examples of storage 8 include a hard disk drive (HDD), a solid state drive (SSD), a magnetic disk, a magneto-optical disk, a compact disc read-only memory (CD-ROM), a digital versatile disc read-only memory (DVD-ROM), and a semiconductor memory. Storage 8 may be an internal medium directly connected to the bus of computer 5, or an external medium connected to computer 5 via interface 9 or a communication line. In addition, when this program is distributed to computer 5 via a communication line, computer 5 that receives the program may load the program into main memory 7 and execute the above-mentioned processing. In at least one embodiment, storage 8 is a non-transitory tangible storage medium.

[0055] The program may also implement some of the functions described above. Furthermore, the program may be a file that can implement the functions described above in combination with a program already recorded in the computer system, a so-called differential file (differential program).

[0056] Although several embodiments of the present disclosure have been described, these embodiments are merely examples and do not limit the scope of the disclosure. Various additions, omissions, substitutions, and modifications may be made to these embodiments without departing from the spirit of the disclosure.

[0057] Note that part or all of the above-described embodiments can be described as, but are not limited to, the following supplementary notes.

[0058] (Appendix 1) a control mechanism for determining whether the network is down or not based on a plurality of first health-check frames transmitted from a server other than the server itself, before receiving a first health-check frame among the plurality of first health-check frames transmitted from the server itself; A server comprising:

[0059] (Appendix 2) The control mechanism Even if some of the plurality of first health check frames are lost, if the next first health check frame is received before the count value of the received first health check frame among the plurality of first health check frames exceeds a certain value, the network is determined to be not down. The server described in Appendix 1.

[0060] (Appendix 3) The control mechanism limiting the number of packets in the health check frame to a predetermined number based on a load during the health check; A server as described in Appendix 1 or Appendix 2.

[0061] (Appendix 4) The other server a control mechanism that transmits the initial first health check frame to the other server before receiving the second health check frame from the server itself, and determines whether the network is down based on the second health check frame; Equipped with 1. A server according to any one of Annexes 1 to 3.

[0062] (Appendix 5) a server according to any one of Appendix 1 to Appendix 4; a server separate from the server; A processing system comprising:

[0063] (Appendix 6) In the health check, before receiving a first health check frame among a plurality of first health check frames that are health check frames transmitted from a server other than the server itself, transmitting a second health check frame that is a health check frame to the other server; determining whether the network is down based on the plurality of first health check frames; A processing method comprising:

[0064] (Appendix 7) On the computer, In the health check, before receiving a first health check frame among a plurality of first health check frames that are health check frames transmitted from a server other than the server itself, transmitting a second health check frame that is a health check frame to the other server; determining whether the network is down based on the plurality of first health check frames; A program that executes the following. [Explanation of symbols]

[0065] 1. Processing System 5. Computer 6, 205···CPU 7. Main memory 8. Storage 9. Interface 10, 10a, 10b, 300... servers 20. Communication equipment 101 Network equipment 301, 1013... Control mechanism 1011...NIC(Network Interface Card) 1012...NIC driver 1013a Frame sending and receiving function 1013a5···Socket API 1013b···Counter function 1013c···Timer function 1013d Alive / dead monitoring flag setting function

Claims

1. a control mechanism for determining whether the network is down or not based on a plurality of first alive-check frames transmitted from a server other than the server itself, before receiving a first first alive-check frame among the plurality of first alive-check frames transmitted from the server itself; A server comprising:

2. The control mechanism Even if some of the plurality of first alive-check frames are lost, if the next first alive-check frame is received before the count value of the received first alive-check frame among the plurality of first alive-check frames exceeds a certain value, it is determined that the network is not down. The server of claim 1 .

3. The control mechanism limiting the number of packets in the health check frame to a predetermined number based on a load during the health check; The server of claim 1 .

4. The other server a control mechanism that transmits the initial first health check frame to the other server before receiving the second health check frame from the server itself, and determines whether the network is down based on the second health check frame; Equipped with The server of claim 1 .

5. A server according to any one of claims 1 to 4; a server separate from the server; A processing system comprising:

6. In the health check, before receiving a first first health check frame among a plurality of first health check frames which are health check frames transmitted from a server other than the server itself, transmitting a second health check frame which is a health check frame to the other server; determining whether or not a network is down based on the plurality of first health check frames; A processing method comprising:

7. On the computer, In the health check, before receiving a first first health check frame among a plurality of first health check frames which are health check frames transmitted from a server other than the server itself, transmitting a second health check frame which is a health check frame to the other server; determining whether or not a network is down based on the plurality of first health check frames; A program that executes the following.

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