JP5955815B2 - Address assignment apparatus, communication system, management method, and management program - Google Patents

Description

  The present invention relates to an address assignment device, a communication system, a management method, and a management program.

  In recent years, cloud computing has become widespread, and a virtual environment is constructed using resources of a physical server installed in a data center to provide various services to users. In addition, an L2 network is built across different data centers using virtual switches.

  For example, a description will be given by taking as an example a company (Z) that implements a department server, an accounting server, an attendance / leaving management server, a file server, and the like by a virtual machine (hereinafter sometimes referred to as VM (Virtual Machine)). In the company (Z), the virtual machine (A) and the virtual machine (B) are operated at the data center (X) of the base (Sapporo), and the virtual machine (C) is operated at the data center (Y) of the base (Fukuoka). The virtual machine (D) is operated. Then, the data center (X) and the data center (Y) are connected by a virtual L2 network using a virtual switch such as Open vSwitch.

  In this way, in the company (Z), by realizing communication between virtual machines that operate in different data centers and provide each service, employees at each base can be made independent of the base, Provide various services.

Hisashi Ishii, Kazue Ueno, Keisuke Tagami, Koji Iida, Tomonari Fujita, Kazutaka Morita, "Open Source laaS Cloud Platform OpenStack", NTT Technology Journal Vol.23, No.8, 2011. Hideo Kitazume, Takaaki Koyama, Yoshitake Tajima, Toshiharu Kishi, Atsuko Inoue, "Network Virtualization Technology that Supports Cloud Services", NTT Technology Journal Vol.23, No.10, 2011.

  However, the above technique has a problem in that when a virtual machine migration or the like occurs, the communication path becomes redundant and communication delay occurs.

  As an example, the company (Z) will be described as an example. In a situation where an employee's personal computer (hereinafter sometimes referred to as a PC) is connected to each site using the Internet or the like and uses a virtual machine. Suppose that a virtual machine (B) is migrated to the data center (Y) of the base (Fukuoka) in order to improve convenience etc. as the employee of the base (Sapporo) travels to the base (Fukuoka). . In this case, the default gateway of the PC of the employee who uses the Internet is the IP address of the router designated by ISP (Internet Service Provider). The default gateway of the migrated virtual machine (B) is set to the router of the migration source data center (X).

  For this reason, when an employee accesses the virtual machine (B) from a business trip destination in Fukuoka, the employee's PC sends a response from the virtual machine (B) to the data center (Y) at the business trip destination (Fukuoka), The data is received via the virtual L2 network between the data centers and the data center (X) of the base (Sapporo) that is the business trip source. In other words, the employee's PC receives a response from the virtual machine (B) via the business trip source even though the virtual machine (B) is migrated to the business trip destination in accordance with the business trip. As described above, the communication distance from the virtual machine (B) to the user terminal is increased, and the delay is increased unnecessarily.

  Although it is conceivable to change the default gateway of the virtual machine (B), it is not realistic from the viewpoint of security to allow an employee who is not an administrator to change the network settings.

  An embodiment of the disclosure has been made in view of the above, and an object thereof is to provide an address assignment device, a communication system, a management method, and a management program that can reduce communication delay.

  One embodiment of the present application is an address assignment device that transmits network setting information including an address of a default gateway to be passed when an information processing device performs data communication, to the information processing device, and holds the information processing device An address change information transmitting unit for transmitting address change information for changing the address information of the address assigning device to the information processing device, and message processing for receiving a response message of the message after transmitting the message to the information processing device Unit, a response time measuring unit for measuring a response time that is a time from transmission of the message to reception of the response message of the message, and a transfer order of transfer information between the address allocation devices in the same network segment. Storage unit for storing the transfer order information between the devices, and the measured response time A data transfer unit that transfers the transfer information added with the network setting information to the next address assignment device indicated in the inter-device transfer information, and its own address assignment device is the last indicated in the inter-device transfer information. If the address allocation device is one of the address allocation devices, the response time is the shortest with reference to the response time of its own address allocation device and the response time of each of the other address allocation devices indicated in the transfer information received from the other address allocation devices. A device selection unit that selects an address allocation device, and a network setting information transmission unit that transmits network setting information of the selected address allocation device to the information processing device.

  According to an embodiment of the present application, communication delay can be reduced.

FIG. 1 is a diagram illustrating an example of the entire structure of the system according to the first embodiment. FIG. 2 is a diagram illustrating a hierarchical structure of physical servers that operate VMs. FIG. 3 is a functional block diagram showing a functional configuration of the DHCP server. FIG. 4 is a diagram illustrating an example of inter-device transfer order information. FIG. 5 is a functional block diagram showing the functional configuration of the VM. FIG. 6 is a diagram illustrating a processing procedure of the DHCP server. FIG. 7 is a diagram illustrating a VM processing procedure. FIG. 8 is a diagram illustrating an example of VM migration. FIG. 9 is a diagram illustrating an example of a processing procedure of the system when the migration of FIG. 8 is performed. FIG. 10 is a diagram illustrating an example of a processing procedure of the system of the second embodiment when the migration of FIG. 8 is performed. FIG. 11 is a diagram illustrating a computer that executes a management program.

  Hereinafter, embodiments of the present invention will be described by dividing them into a first embodiment and a second embodiment with reference to the drawings. In addition, this invention is not limited by each embodiment. Further, the embodiments described below can be appropriately combined within a consistent range.

[First Embodiment]
(overall structure)
FIG. 1 is a diagram illustrating an example of the overall configuration of a system according to the first embodiment. As shown in FIG. 1, the system is a system that connects, for example, corporate bases via a network. A base (Sapporo) 1 and a base (Fukuoka) 11 each having a data center are connected by a network 20 such as the Internet. The

(Base (Sapporo))
The base (Sapporo) 1 has a user terminal 10 and a data center 2. The user terminal 10 is a terminal device that accesses a virtual machine operating in the data center 2 or the data center 12 of the base (Fukuoka) 11 and uses various services, such as a notebook computer or a smartphone.

  The data center 2 is a data center in which one or more physical servers are installed and a virtual machine 40 that is an information processing apparatus is operated using physical resources of the physical server. The physical resources include a communication interface, a processor, a memory, and a hard disk.

  Specifically, the data center 2 includes a CE (Customer Edge) router 3, a router 4, an OVS (Open vSwitch) 5, a VM (A) 40a, a VM (B) 40b, and a DHCP (Dynamic Host Configuration Protocol) server 30a. Have. The CE router 3 is an edge router installed at the boundary between a telecommunications carrier network such as a wide area Ethernet and a corporate network such as a corporate LAN (Local Area Network). The CE router 3 is realized by a physical device. .

  The router 4 is a router that divides the data center 2 of the base (Sapporo) 1 and the data center 12 of the base (Fukuoka) 11 into the same network segment (segment) 22 in the corporate network. That is, the router 4 relays communication between the user terminal 10 and each VM 40 in each data center. The interface 4a of the router 4 is an interface connected to the CE router 3, and “IP (4a)” is set as an IP (Internet Protocol) address. The interface 4b of the router 4 is an interface connected to each VM 40, and “IP (10)” is set as the IP address.

  Therefore, the user terminal 10 used at the base (Sapporo) 10 is connected with “IP (4a)” as a default gateway. Therefore, the user terminal 10 accesses via the router 4 when accessing each VM 40. The router 4 may be realized with a virtual machine or a physical device.

  The OVS 5 is a switch that relays between each router of each data center and each VM 40, and is a virtual switch that connects the data centers with the virtual L2 network 21 in cooperation with the OVS 15 of the data center 12. For example, the OVS 5 is connected to the interface 4 b of the router 4, the VM (A) 40 a, the VM (B) 40 b, and the OVS 15 of the data center 12.

  The VM (A) 40a is a virtual machine that executes, for example, a Web server or a DB server, and “IP (A)” is set as an IP address. The VM (B) 40b is a virtual machine that executes, for example, a Web server or a DB server, and “IP (B)” is set as the IP address. These VMs 40 communicate with the user terminal 10 via the OVS 5.

  The DHCP server (address allocation device) 30a transmits network setting information to the VMs 40 (VM (A) 40a, VM (B) 40b, VM (C) 40c, VM (D) 40d) in the same segment 22. The network setting information is setting information for the VM 40 to perform data communication, and includes an IP address assigned to the VM 40, an IP address of a default gateway used by the VM 40, and the like.

  Each DHCP server 30a holds the IP address of the default gateway in the data center (or base) to which the own DHCP server 30a belongs, and the DHCP server 30a transmits network setting information to the VM 40 in the same segment 22. In this case, the IP address of the default gateway (router 14) and the IP address assigned to the VM 40 are transmitted. For example, the DHCP server 30a holds the IP address of the default gateway (router 4) in the data center 2 to which the DHCP server 30a belongs, and when transmitting network setting information to the VM 40, this default gateway (router 4) including the IP address assigned to the VM 40. The DHCP server 30 (30a, 30b) installed in the same segment 22 is set with the same IP address.

(Base (Fukuoka))
The base (Fukuoka) 11 has a data center 12. The data center 12 is a data center in which one or more physical servers are installed and a virtual machine is operated using physical resources of the physical server.

  Specifically, the data center 12 includes a CE router 13, a router 14, an OVS 15, a VM (C) 40c, and a VM (D) 40d. The CE router 13 is an edge router installed at the boundary between a communication carrier network such as a wide area Ethernet and a corporate network such as a corporate LAN. The CE router 13 is realized by a physical device.

  The router 14 is a router that divides the data center 2 of the base (Sapporo) 1 and the data center 12 of the base (Fukuoka) 11 into the same segment 22 in the corporate network. That is, the router 14 relays communication between the external device and each VM 40 in each data center. The interface 14a of the router 14 is an interface connected to the CE router 13, and “IP (14a)” is set as the IP address. The interface 14b of the router 4 is an interface connected to each VM 40, and “IP (10)” is set as the IP address. The router 14 may be realized by a virtual machine or a physical device.

  The OVS 15 is a switch that relays between each router and each VM 40 of each data center, and is a virtual switch that connects the data centers with the virtual L2 network 21 in cooperation with the OVS 5 of the data center 12. For example, the OVS 15 is connected to the interface 14 b of the router 14, the VM (C) 40 c, the VM (D) 40 d, and the OVS 5 of the data center 1.

  The VM (C) 40c is a virtual machine that executes, for example, a Web server or a DB server, and “IP (C)” is set as the IP address. The VM (D) 40d is a virtual machine that executes, for example, a Web server or a DB server, and “IP (D)” is set as the IP address. These VMs 40 communicate with external devices outside the data center via the OVS 15.

  The DHCP server 30b transmits network setting information to the VMs 40 (VM (A) 40a, VM (B) 40b, VM (C) 40c, VM (D) 40d) in the same segment 22. The network setting information is setting information for the VM 40 to perform data communication, and includes an IP address assigned to the VM 40, an IP address of a default gateway used by the VM 40, and the like.

  Each DHCP server 30b holds the IP address of the default gateway in the data center (or base) to which the own DHCP server 30b belongs, and the DHCP server 30a transmits the network setting information to the VM 40 in the same segment 22. In this case, the IP address of the default gateway (router 14) and the IP address assigned to the VM 40 are transmitted. For example, the DHCP server 30b holds the IP address of the default gateway (router 14) in the data center 12 to which the DHCP server 30b belongs, and when transmitting network setting information to the VM 40, this default gateway (router 14) including the IP address assigned to the VM 40.

(Network configuration)
As described above, the same IP address “IP (10)” is set in the interface 4 b of the router 4 and the interface 14 b of the router 14. In addition, each VM operates in the same segment 22 although operating bases are different. In other words, the router 4, the router 14, the OVS 5, the OVS 15, the VM (A) 40a, the VM (B) 40b, the VM (C) 40c, and the VM (D) 40d are connected by the virtual L2 network 21 and operate in the same segment 22. To do. Therefore, the router 14 of the base (Fukuoka) 11 and the VM (A) 40a and VM (B) 40b are communicably connected, and the router 4 of the base (Sapporo) 1 and the VM (C) 40c and VM (D) 40d is connected to be communicable.

(Hierarchical structure)
FIG. 2 is a diagram illustrating a hierarchical structure of physical servers that operate VMs. Here, an example in which the VM 40 is operated by one physical server is described as an example, but the present invention is not limited to this, and the operation can be performed by using a plurality of physical servers.

  In the data center 2, the physical server 6 operates, and in the data center 12, the physical server 16 operates. Each physical server is a general server device, and includes hardware, a processor, a memory, and the like.

  The physical server 6 of the data center 2 operates virtual software 6b such as a hypervisor on the hardware 6a to provide a virtual environment. The virtualization software 6b operates the virtual switch 6c.

  Similarly, the physical server 16 in the data center 12 operates virtualization software 16b such as a hypervisor on the hardware 16a to provide a virtual environment. The virtualization software 16b operates the virtual switch 16c.

  Here, the virtual switch 6c and the virtual switch 16c are realized using, for example, Open vSwitch, KVM, and the like, and construct the virtual L2 network 21. That is, different data centers are connected to each other via a virtual network.

  Each virtualization software of each physical server operates a virtual machine in a state where the virtual L2 network 21 can be used. Specifically, the virtualization software 6b operates the VM (A) 40a and the VM (B) 40b using the physical resources of the physical server 6, and each VM 40 is connected to the virtual L2 network via the virtual switch 6c. 21 is connected. Similarly, the virtualization software 16b operates the VM (C) 40c and the VM (D) 40d using the physical resources of the physical server 16, and passes each VM 40 to the virtual L2 network 21 via the virtual switch 16c. Connecting.

(Configuration of DHCP server)
Next, the configuration of the DHCP server shown in FIG. 1 will be described. First, an outline of the operation of the DHCP server 30 will be briefly described. First, each DHCP server 30 in the same segment 22 measures the time (response time) until the response of the DHCP message is received from the VM 40 after transmitting the DHCP message to the VM 40. Each DHCP server 30 sequentially transfers transfer information including network setting information in the DHCP server 30 between the DHCP servers 30 during the measured response time. The DHCP server 30 that has finally reached the transfer information refers to the received transfer information, specifies the DHCP server 30 with the shortest response time, selects the network setting information of the specified DHCP server 30, and selects the VM 40 Send to.

  In the following description, the DHCP message transmitted from the DHCP server 30 to the VM 40 is DHCP FORCERENEW (message for instructing the DHCP client to reconfigure the DHCP server 30), and the response message received from the DHCP server 30 is DHCP RENEW. The case of (a message notifying that the DHCP server 30 has been reset) will be described as an example, but the present invention is not limited to this.

  FIG. 3 is a functional block diagram showing a functional configuration of the DHCP server. As illustrated in FIG. 3, the DHCP server 30 includes a communication control unit 31, a storage unit 32, and a control unit 33.

  The communication control unit 31 has an interface and controls communication of other devices. For example, the communication control unit 31 controls communication with the VM 40. An IP address is set for the interface. This IP address is, for example, “IP (10)”.

  The storage unit 32 is a storage device such as a memory or a hard disk, and stores address information and inter-device transfer order information.

  The address information is information that is the basis of the network setting information transmitted to the VM 40, and is information that indicates the IP address of the router of the default gateway in the data center (or base) to which the own DHCP server 30 belongs.

  The inter-device transfer order information is information indicating the transfer order of transfer information between the DHCP servers 30. FIG. 4 is a diagram illustrating an example of inter-device transfer order information. For example, as illustrated in FIG. 4, the transfer order between the DHCP server 30 a and the DHCP server 30 b is described in the inter-device transfer order information.

  The address information and the inter-device transfer order information are input via the communication control unit 31 and the control unit 33 by an administrator of the system.

  The control unit 33 is an electronic circuit such as a processor, and controls the entire DHCP server 30. The control unit 33 includes a network setting information creation unit 330, an address change information transmission unit 331, a DHCP message processing unit 332, a response time measurement unit 333, a data transfer unit 334, a device selection unit 335, and a network setting information transmission unit 336. .

  The network setting information creation unit 330 creates network setting information of the VM 40 with reference to the address information. Specifically, the network setting information creation unit 330 determines an IP address to be assigned to the VM 40, and creates network setting information including the determined IP address and the IP address of the default gateway indicated in the address information.

  The address change information transmission unit 331 transmits a GARP (Gratuitous ARP (Address Resolution Protocol)) message as address change information to the migrated VM 40 before transmitting the DHCP message. By transmitting this GARP message (hereinafter abbreviated as GARP as appropriate), the information on the IP address and MAC address of the DHCP server 30 in the ARP table of the VM 40 is flushed.

  The reason why the information in the ARP table of the VM 40 is flushed in this way is that the same IP address is set for each DHCP server 30 in the same segment 22 in this system. In other words, the VM 40 is assigned an IP address in advance by any DHCP server 30 in the same segment 22, but if the information of the DHCP server 30 remains in the ARP table, the VM 40 This is because communication with the DHCP server 30 (the IP address is the same but the MAC address is different) cannot be performed.

  The DHCP message processing unit 332 transmits DHCP FORCERENEW to the VM 40 after the GARP transmission to the VM 40 by the address change information transmission unit 331. Thereafter, when the DHCP message processing unit 332 receives DHCP RENEW from the VM 40 in response to the transmitted DHCP FORCERENEW, the DHCP message processing unit 332 returns a DHCP ACK to the VM 40. The DHCP ACK here includes network setting information for the VM 40. This network setting information includes an IP address of a default gateway used by the VM 40 and an IP address assigned to the VM 40.

  The response time measurement unit 333 measures the time (response time) from when the DHCP server 30 transmits a DHCP message to the VM 40 until the response message of the DHCP message is received. For example, the response time measurement unit 333 measures the time (response time) from when DHCP FORCERENEW is transmitted to the VM 40 until when DHCP RENEW is received from the VM 40. By measuring the response time, the communication delay time between the DHCP server 30 and the VM 40 is known. The response time measurement unit 333 outputs the measured response time to the data transfer unit 334 and the device selection unit 335.

  The data transfer unit 334 creates transfer information including the response time measured by the response time measurement unit 333, identification information of its own DHCP server 30, and network setting information created by the network setting information creation unit 330. Then, the data transfer unit 334 transfers the created transfer information to the DHCP server 30 in the next order of its own DHCP server 30 in the inter-device transfer order information.

  For example, the data transfer unit 334 of the DHCP server 30b adds the response time of its own DHCP server 30b and the network setting information to the transfer information from the DHCP server 30a, and transfers as illustrated in Table 1 below. Create information.

  When the own DHCP server 30 is the first DHCP server 30 in the inter-device transfer order information, transfer information with the measured response time and the network setting information added is created and transferred to the next DHCP server 30 To do. Also, in the inter-device transfer order information, when the own DHCP server 30 is the second or later DHCP server 30 other than the last, the response measured by the own DHCP server 30 to the transfer information received from the other DHCP server 30 Transfer information to which time and network setting information are added is created and transferred to the next DHCP server 30. In the inter-device transfer order information, when the own DHCP server 30 is the last DHCP server 30, the created transfer information is output to the device selection unit 335 and the network setting information transmission unit 336.

  The device selection unit 335 compares the response times of the DHCP servers 30 indicated in the transfer information output from the data transfer unit 334, and specifies (selects) the DHCP server 30 having the shortest response time.

  The network setting information transmission unit 336 reads the network setting information of the DHCP server 30 selected by the device selection unit 335 from the transfer information (see Table 1) output from the data transfer unit 334, and transmits the DHCP RENEW source To the VM 40. For example, when the DHCP server 30 selected by the device selection unit 335 is the DHCP server 30b, the network setting information of the DHCP server 30b is read from the transfer information and transmitted to the VM (B) 40b that is the DHCP RENEW transmission source. . Thereby, the network setting information of the DHCP server 30 with the shortest response time from the VM 40 (that is, the shortest communication delay) is transmitted to the VM 40. That is, the VM 40 can receive network setting information from the DHCP server 30 at the base (or data center) after migration.

(VM configuration)
Next, the configuration of the VM 40 illustrated in FIG. 1 will be described. FIG. 5 is a functional block diagram showing the functional configuration of the VM. As illustrated in FIG. 5, the VM 40 includes a communication control unit 41, a storage unit 42, and a control unit 43.

  The communication control unit 41 has an interface and controls communication of other devices. For example, the communication control unit 41 controls communication with the user terminal 10 via the OVS 5, the router 4, and the CE router 3. An IP address is set for the interface. This IP address is, for example, “IP (A)”.

  The storage unit 42 is a storage device such as a memory or a hard disk, and stores an ARP table and network setting information.

  The ARP table is information in which an IP address and a MAC address of a communication destination device are associated with each other. This ARP table also includes the IP address of the DHCP server 30 and the MAC address of the DHCP server 30.

  The network setting information is setting information for the VM 40 to communicate via the network 20 such as an IP address assigned to the VM 40 and a default gateway IP address used by the VM 40.

  The control unit 43 is an electronic circuit such as a processor and controls the entire VM 40. The control unit 43 includes an ARP table update unit 431, a DHCP message transmission / reception unit 432, and a communication processing unit 434.

  When receiving the GARP from the DHCP server 30, the ARP table update unit 431 flushes the information on the IP address and the MAC address of the DHCP server 30 in the ARP table. Thereafter, when the DHCP message transmission / reception unit 432 receives the DHCP ACK from the DHCP server 30, the ARP table update unit 431 updates the MAC address of the DHCP server 30 in the ARP table to the MAC address indicated in the DHCP ACK.

  For example, when the MAC address of the DHCP server 30a (for example, the IP address “10.1.1.30”) is described in the ARP table, the DHCP server 30b (for example, the IP address “10.1.1.30”) is used in the DHCP message transmission / reception unit 432. When receiving the DHCP ACK from the ARP table, the ARP table updating unit 431 updates, for example, the MAC address for the IP address “10.1.1.30” to the MAC address of the DHCP server 30b (see Table 2). That is, when receiving the DHCP ACK from the DHCP server 30 having the same IP address, the ARP table updating unit 431 updates the ARP table with the MAC address of the DHCP server 30 indicated in the recently received DHCP ACK.

  The DHCP message transmission / reception unit 432 transmits / receives a DHCP message to / from the DHCP server 30. For example, when receiving DHCP FORCERENEW from the DHCP server 30, the DHCP message transmission / reception unit 432 returns DHCP RENEW to the DHCP server 30 and then receives a DHCP ACK from the DHCP server 30. Here, the network setting information included in the DHCP ACK received from the DHCP server 30 indicates the same default gateway IP address that has been set in the VM 40 until then.

  The network setting information updating unit 433 updates the network setting information in the storage unit 42 using the network setting information indicated in the DHCP ACK received by the DHCP message transmission / reception unit 432.

  The communication processing unit 434 communicates with other devices via the communication control unit 41 with reference to the network setting information and the ARP table in the storage unit 42. For example, the communication processing unit 434 communicates with other devices via a default gateway indicated in the network setting information. Further, the communication processing unit 434 refers to the ARP table, obtains the MAC address of the device from the IP address of the communication destination device, and performs communication with the device.

(Processing procedure)
(Processing procedure of DHCP server)
Next, the processing procedure of the DHCP server 30 shown in FIG. 3 will be described with reference to FIG. FIG. 6 is a diagram illustrating a processing procedure of the DHCP server.

  When migration of the VM 40 is performed, the address change information transmission unit 331 of the DHCP server 30 transmits GARP to the VM 40 (S1). Thereafter, the DHCP message processing unit 332 transmits DHCP FORCERENEW to the VM 40 (S2), and receives DHCP RENEW from the VM 40 (S3). Then, the response time measurement unit 333 measures the time (response time) until DHCP RENEW reception from the VM 40 after DHCP FORCERENEW transmission to the VM 40 (S4).

  After S4, the data transfer unit 334 refers to the inter-device transfer order information to determine whether or not the data transfer order of its own DHCP server 30 is last (S5), and the data transfer order of its own DHCP server 30. If it is not the last (No in S5), the response time measured in S4 and the network setting information are added to the transfer information and transferred to the next DHCP server 30 (S6). If the data transfer unit 334 has already received transfer information from another DHCP server 30, the data transfer unit 334 adds the response time measured in S4 and the network setting information to the received transfer information, and the next DHCP server. Transfer to 30.

  After S6, the DHCP server 30 transmits a DHCP ACK to the VM 40 (S7). This DHCP ACK includes the network setting information of the DHCP server 30 and the MAC address.

  On the other hand, in S5, when the data transfer unit 334 refers to the inter-device transfer order information and determines that the data transfer order of its own DHCP server 30 is the last (Yes in S5), the transfer information is transferred. First, the device selection unit 335 selects the DHCP server 30 having the shortest response time from among the DHCP servers including its own DHCP server 30. Then, the network setting information transmission unit 336 transmits the network setting information transmitted from the selected DHCP server 30 to the VM 40 by DHCP ACK (S8).

  By doing in this way, the DHCP server 30 can transmit the network setting information of the DHCP server 30 having the shortest communication delay from the VM 40 among the DHCP servers 30 in the same segment 22.

(VM processing procedure)
Next, the processing procedure of the VM 40 shown in FIG. 5 will be described with reference to FIG. FIG. 7 is a diagram illustrating a VM processing procedure.

  When receiving the GARP from the DHCP server 30 (S11), the ARP table update unit 431 of the VM 40 clears the ARP table (S12). That is, the ARP table update unit 431 flushes the information of the MAC address of the DHCP server 30 in the ARP table.

  After S12, when receiving DHCP FORCERENEW from the DHCP server 30 (S13), the DHCP message transmission / reception unit 432 transmits DHCP RENEW to the DHCP server 30 (S14), and then receives a DHCP ACK from the DHCP server 30. (S15). Then, the ARP table update unit 431 updates the ARP table with the MAC address of the DHCP server 30 indicated in the received DHCP ACK (S16).

  Further, the network setting information updating unit 433 updates the network setting information in the storage unit 42 with the network setting information indicated in the DHCP ACK received in S15 (S17). As a result, the IP address of the default gateway of the VM 40 is also updated.

  Then, the communication processing unit 434 performs data communication via the default gateway indicated in the updated network setting information (S18).

  The VM 40 executes the above processing every time it receives a GARP from the DHCP server 30.

  A specific example of the processing procedure of the system will be described with reference to FIGS. FIG. 8 is a diagram illustrating an example of VM migration. FIG. 9 is a diagram illustrating an example of a processing procedure of the system when the migration of FIG. 8 is performed. Here, as shown in FIG. 8, the user terminal 10 moves from the base (Sapporo) 1 to the base (Fukuoka) 11, and the VM (B) 40b is migrated from the data center 2 to the data center 12. Explained as an example. In the inter-device transfer order information, it is assumed that the transfer order of the transfer information is DHCP server 30a → DHCP server 30b.

  When migration of the VM (B) 40b to the data center 12 is performed, the address change information transmission unit 331 of the DHCP server 30a transmits GARP to the VM (B) 40b (S21). Thereafter, the DHCP message processing unit 332 of the DHCP server 30a transmits DHCP FORCERENEW (S22), and then receives DHCP RENEW from the VM (B) 40b (S23). Here, the response time measuring unit 333 of the DHCP server 30a measures the time (response time) until the DHCP RENEW is received after transmitting DHCP FORCERENEW to the VM (B) 40b (S24).

  After S24, the data transfer unit 334 of the DHCP server 30a transfers the response time measured in S24 and the network setting information (including the IP address (4a) of the default gateway) as transfer information to the DHCP server 30b (S25). ). Further, the DHCP server 30a transmits a DHCP ACK for DHCP RENEW to the VM (B) 40b (S26).

  In S26, the DHCP ACK transmitted by the DHCP server 30a includes the MAC address and network setting information of the DHCP server 30a, whereby the ARP table is updated and the network setting information is updated in the VM (B) 40b. Is called.

  After receiving the transfer information transmitted from the DHCP server 30a in S25, the DHCP server 30b transmits the GARP to the VM (B) 40b by the address change information transmitting unit 331 (S31). Since S32 to S34 are the same as S22 to S24 described above, description thereof is omitted.

  After S34, the device selection unit 335 of the DHCP server 30b selects the DHCP server 30 having the shortest response time among the DHCP servers 30 based on the transfer information transmitted in S25 and the response time measured in S34. (S35). Then, the network setting information transmission unit 336 receives the network setting information (including the IP address (14a) of the default gateway) of the DHCP server 30 (here, the DHCP server 30b) selected in S35 as a VM (B) using DHCP ACK. It transmits to 40b (S36).

  The network setting information updating unit 433 of the VM (B) 40b updates the network setting information in the storage unit 42 with the network setting information transmitted in S36 (S37), and the communication processing unit 434 indicates the network setting information. Data communication is performed via the default gateway (IP address (14a)) (S38).

  As described above, after the migration of the VM (B) 40b, the network setting information of the DHCP server 30b of the data center 12 is set in the VM (B) 40b. As a result, the VM (B) 40b performs data communication using the router 14 (IP address (14a)) as a default gateway, so that communication delay can be reduced.

[Second Embodiment]
Next, a second embodiment of the present invention will be described. The system of the second embodiment uses IPv6 (Internet Protocol Version 6) as a communication protocol. In this case, the router in the system advertises route information by IPv6.

  In the system of the second embodiment, the default gateway of the VM 40 is set to DHCPv6 Route Option draft-dec-dhcpv6-route-option-05 (URL: http://tools.ietf.org/html/draft-dec- Table 3 below shows messages exchanged between the DHCP server 30 and the VM 40 when using dhcpv6-route-option-05). The left column of Table 3 is a DHCP message for IPv4, and the right column is a DHCPv6 Route Option draft-dec-dhcpv6-route-option-05 message corresponding to the message content.

  That is, when DHCPv6 Route Option draft-dec-dhcpv6-route-option-05 is used for setting the default gateway of the VM 40, the DHCP server 30 transmits Reconfigure instead of DHCP FORCERENEW. Further, the VM 40 transmits Renew as a response to Reconfigure. Further, the DHCP server 30 transmits Reply as a response to Renew from the VM 40.

  In the system of the second embodiment, instead of the DHCP server 30 sending GARP, the link-layer address change of the neighbor advertisement of ICMPv6 (RFC4861) is changed from the link local address of the DHCP server 30 to the link local address of the VM 40. Send. As a result, the link local address of the DHCP server 30 held by the VM 40 is changed. Then, the DHCP server 30 transmits Reconfigure after transmitting the link-layer address change of Neighbor advertisement to the VM 40.

  When measuring the response time, each DHCP server 30 in the system of the second exemplary embodiment measures the time from Reconfigure transmission to the VM 40 until Renew reception from the VM 40. Each DHCP server 30 transfers the added transfer information indicating the measured response time and network setting information to the next DHCP server 30 indicated in the inter-device transfer order information.

  Then, the last DHCP server 30 that has received the transfer information from the other DHCP server 30 refers to the transfer information, and the DHCP server 30 that has the shortest response time among the DHCP servers 30 including its own DHCP server 30. The network setting information of the selected DHCP server 30 is included in Reply and transmitted to the VM 40. Note that the field for inserting network setting information in Reply may be an IA_RT option field defined in draft-dec-dhcpv6-route-option-05.

  Also, when ICMPv6 (see RFC4861) is used for setting the default gateway of the VM 40, the DHCP server 30 changes the link-layer address change of the Neighbor advertisement of the ICMPv6 (RFC4861) instead of the GARP described above. The link local address is transmitted to the link local address of the VM 40. As a result, the link local address set in the VM 40 is changed to the link local address of the DHCP server 30. Further, when measuring the response time described above, the DHCP server 30 uses the time from the Reconfigure transmission to the VM 40 to the reception of Renew from the VM 40. In addition, the DHCP server 30 transmits Reply to the VM 40 after receiving Renew. Note that this response time measurement uses the time from the transmission of the echo request from the router to the VM 40 to the reception of the echo reply from the VM 40 in addition to the time from the Reconfigure transmission to the reception of Renew from the VM 40. May be. Further, the DHCP server 30 may use the time from when Reconfigure is transmitted to the VM 40 to when Reconfigure-Accept is received from the VM 40.

  Then, the DHCP server 30 transfers the added transfer information indicating the measured response time to the next DHCP server 30. The last DHCP server 30 that repeats such processing and receives transfer information from another DHCP server 30 refers to the transfer information, and has a response time in each DHCP server 30 including its own DHCP server 30. The shortest DHCP server 30 (that is, the DHCP server 30 with the shortest communication delay) is selected, and an ICMPv6 Router advertisement to the VM 40 is instructed to the selected DHCP server 30. Upon receiving such an instruction, the DHCP server 30 instructs the router serving as the default gateway of the data center (base) to which the DHCP server 30 belongs to an ICMPv6 Router advertisement to the VM 40. Upon receiving this instruction, the router performs an ICMPv6 Router advertisement (router advertisement) toward the link local address of the VM 40. As a result, an IPv6 IP address is set in the VM 40, and the advertisement source router is set as the default gateway. That is, the router with the shortest communication delay is set as the default gateway in the VM 40.

  A specific example of the processing procedure of the system when ICMPv6 (see RFC4861) is used for setting the default gateway of the VM 40 will be described with reference to FIG. FIG. 10 is a diagram illustrating an example of a processing procedure of the system of the second embodiment when the migration of FIG. 8 is performed. Again, as shown in FIG. 8, the user terminal 10 moves from the base (Sapporo) 1 to the base (Fukuoka) 11, and the VM (B) 40b is migrated from the data center 2 to the data center 12. Explained as an example. In the inter-device transfer order information, it is assumed that the transfer order of the transfer information is from the DHCP server 30a in the data center 2 to the DHCP server 30b in the data center 12.

  When migration of the VM (B) 40b to the data center 12 is performed, the DHCP server 30a of the data center 2 changes the link-layer address change of the Neighbor advertisement from the link local address of the DHCP server 30a to the VM (B) 40b. Transmit to the link local address (S41). Thereafter, the DHCP server 30a of the data center 2 transmits Reconfigure (S42), and then receives Renew from the VM (B) 40b (S43). Here, the DHCP server 30a measures the time (response time) until it receives Renew after transmitting Reconfigure to the VM (B) 40b (S44).

  After S44, the DHCP server 30a of the data center 2 transfers the response time measured in S44 to the router B of the data center 12 as transfer information (S45). Also, the DHCP server 30a of the data center 2 transmits a Reply for Renew to the VM (B) 40b (S46).

  After receiving the transfer information transmitted from the DHCP server 30a of the data center 2 in S45, the router B of the data center 12 transmits a Neighbor advertisement link-layer address change to the VM (B) 40b (S51). Since S52 to S54 are the same as S42 to S44 described above, description thereof will be omitted.

  After S54, the DHCP server 30b of the data center 12 selects the DHCP server 30 having the shortest response time among the DHCP servers 30 based on the transfer information transmitted in S45 and the response time measured in S54. (S55). Then, the DHCP server 30b of the data center 12 instructs the DHCP server 30 selected in S56 to perform ICMPv6 Router advertisement (router advertisement) to the VM (B) 40b (S56). That is, the DHCP server 30 instructs the router serving as the default gateway of the site to which the DHCP server 30 belongs to ICMPv6 Router advertisement to the VM (B) 40b. Upon receiving this instruction, the router performs ICMPv6 Router advertisement to the VM (B) 40b (S58). That is, the router advertises network setting information having its own router as a default gateway to the VM (B) 40b. Further, the DHCP server 30b of the data center 12 transmits a Reply for Renew received in S53 to the VM (B) 40b (S54).

  The network setting information updating unit 433 of the VM (B) 40b updates the network setting information in the storage unit 42 by the router advertisement received in S58 (S59). That is, the network setting information updating unit 433 of the VM (B) 40b updates the default gateway to the advertisement source router (for example, the router 14 of the data center 12). Thereafter, the communication processing unit 434 performs data communication via a default gateway (for example, the router 14 of the data center 12) indicated in the network setting information (S60).

  In S55, when the DHCP server 30b of the data center 12 determines that the router with the shortest response time is its own router, the DHCP server 30b itself instructs the router 14 to perform ICMPv6 Router advertisement. Upon receiving this instruction, the router 14 advertises the router to the VM (B) 40b.

  As described above, after migration of the VM (B) 40b, the DHCP server 30 having the shortest response time (for example, the DHCP server 30b of the data center 12) sends the VM (B) to the router serving as the default gateway of the site to which the DHCP server 30 belongs. Since the router advertisement to 40b is instructed, the router with the shortest response time is set as the default gateway in the VM (B) 40b. Thereby, the VM (B) 40b can reduce the communication delay.

(effect)
In this way, the present invention can be implemented even when the protocol used in the system is IPv6.

[Other Embodiments]
Note that the data transfer unit 334 of the DHCP server 30 may transfer the transfer information without including the network setting information of the DHCP server 30. In this case, the network setting information transmission unit 336 instructs the DHCP server 30 selected by the device selection unit 335 (that is, the DHCP server 30 with the shortest response time) to transmit the network setting information of the DHCP server 30. To do. Upon receiving such an instruction, the DHCP server 30 creates network setting information with reference to its own address information, and transmits it to the VM 40.

(effect)
Even in this way, when the migration of the VM 40 is performed between the data centers, the default gateway with the shortest communication delay is set in the VM 40, so that the communication delay can be reduced.

  Note that the network setting information transmitted from the DHCP server 30 to the VM 40 may include an IP address of a DNS (Domain Name System) server installed at a location to which the DHCP server 30 belongs. As a result, when the VM 40 is migrated between data centers, the VM 40 uses a DNS server installed at the migration destination base. Therefore, after the migration of the VM 40, the communication delay when the VM 40 specifies the IP address of the communication destination from the host name of the communication destination can be reduced.

(System configuration etc.)
Each component of each illustrated device is functionally conceptual, and does not necessarily need to be the same as the physically illustrated component. In other words, the specific form of distribution / integration of each device is not limited to that shown in the figure, and all or a part thereof may be functionally or physically distributed or arbitrarily distributed in arbitrary units according to various loads or usage conditions. Can be integrated and configured.

  In addition, among the processes described in the present embodiment, all or a part of the processes described as being automatically performed can be manually performed. Further, all or any part of each processing function performed in each device may be realized by a CPU and a program analyzed and executed by the CPU, or may be realized as hardware by wired logic.

(program)
In addition, it is possible to create a program in which processing executed by the DHCP server 30 according to the above-described embodiment is described in a language that can be executed by a computer. In this case, when the computer executes the management program, the same effect as in the above embodiment can be obtained. Further, the management program may be recorded on a computer-readable recording medium, and the management program recorded on the recording medium may be read into the computer and executed to execute the same processing as in the above embodiment. Hereinafter, an example of a computer that executes a management program that implements the same functions as the DHCP server 30 and the router illustrated in FIG. 3 and the like will be described.

  FIG. 11 is a diagram illustrating a computer that executes a management program. As illustrated in FIG. 11, the computer 1000 includes, for example, a memory 1010, a CPU 1020, a hard disk drive interface 1030, a disk drive interface 1040, a serial port interface 1050, a video adapter 1060, and a network interface 1070. These units are connected by a bus 1080.

  The memory 1010 includes a ROM (Read Only Memory) 1011 and a RAM 1012. The ROM 1011 stores a boot program such as BIOS (Basic Input Output System). The hard disk drive interface 1030 is connected to the hard disk drive 1090. The disk drive interface 1040 is connected to the disk drive 1041. For example, a removable storage medium such as a magnetic disk or an optical disk is inserted into the disk drive 1041. For example, a mouse 1110 and a keyboard 1120 are connected to the serial port interface 1050. For example, a display 1130 is connected to the video adapter 1060.

  Here, as shown in FIG. 11, the hard disk drive 1090 stores, for example, an OS 1091, an application program 1092, a program module 1093, and program data 1094. Each table described in the above embodiment is stored in the hard disk drive 1090 or the memory 1010, for example.

Further, the management program is stored in the hard disk drive 1090 as a program module in which a command executed by the computer 1000 is described, for example.
Specifically, an address change information transmission step for executing information processing similar to that of the address change information transmission unit 331 of the DHCP server 30 described in the above embodiment, and message processing for executing information processing similar to that of the DHCP message processing unit 332 Step, response time measurement step for executing information processing similar to the response time measurement unit 333, data transfer step for executing information processing similar to the data transfer unit 334, and device selection for executing information processing similar to the device selection unit 335 The hard disk drive 1090 stores a program module in which a step and a network setting information transmission step for executing the same information processing as the network setting information transmission unit 336 are described.

  Further, data used for information processing by the management program is stored in the hard disk drive 1090 as program data, for example. Then, the CPU 1020 reads out the program module 1093 and the program data 1094 stored in the hard disk drive 1090 to the RAM 1012 as necessary, and executes the above-described procedures.

  The program module 1093 and the program data 1094 related to the management program are not limited to being stored in the hard disk drive 1090. For example, the program module 1093 and the program data 1094 are stored in a removable storage medium and read by the CPU 1020 via the disk drive 1041 or the like. May be. Alternatively, the program module and program data relating to the management program are stored in another computer connected via a network such as a LAN (Local Area Network) or a WAN (Wide Area Network), and are executed by the CPU 1020 via the network interface 1070. It may be read out.

1 base (Sapporo)
2, 12 Data center 3, 13 CE router 4, 14 Router 5, 15 OVS
11 bases (Fukuoka)
20 network 21 virtual L2 network 22 network segment 14a, 14b interface 30, 30a, 30b DHCP server 40 virtual machine 31, 41 communication control unit 32, 42 storage unit 33, 43 control unit 330 network setting information creation unit 331 address change information transmission Unit 332 DHCP message processing unit 333 response time measurement unit 334 data transfer unit 335 device selection unit 336 network setting information transmission unit 431 address change information transmission unit 431 ARP table update unit 432 DHCP message transmission / reception unit 433 network setting information update unit 434 communication processing Part

Claims (7)

An address assignment device that transmits network setting information including an address of a default gateway to be passed when the information processing device performs data communication to the information processing device,
An address change information transmission unit for transmitting address change information for changing the address information of the address assignment device held by the information processing device to the information processing device;
A message processing unit that receives a response message of the message after transmitting the message to the information processing apparatus;
A response time measuring unit that measures a response time that is a time from transmission of the message to reception of a response message of the message;
A storage unit for storing inter-device transfer order information indicating a transfer order of transfer information between address allocation devices in the same network segment;
A data transfer unit for transferring the transfer information to which the measured response time and the network setting information are added to the next address assignment device indicated in the inter-device transfer order information;
When its own address assignment device is the last address assignment device indicated in the inter-device transfer order information, the response time of its own address assignment device and other addresses indicated in the transfer information received from other address assignment devices Referring to the response time of each of the allocation devices, a device selection unit for selecting the address allocation device with the shortest response time;
An address assignment apparatus comprising: a network setting information transmission unit that transmits network setting information of the selected address assignment apparatus to the information processing apparatus. The data transfer unit is
The transfer information with the measured response time added is transferred to the next address allocation device indicated in the inter-device transfer order information,
The network setting information transmission unit
2. The address assignment device according to claim 1, wherein the address assignment device instructs the selected address assignment device to transmit network setting information of the address assignment device to the information processing device. When the communication protocol between the information processing device and the address assignment device is IPv4 (Internet Protocol version 4),
The address change information is a GARP (Gratuitous ARP (Address Resolution Protocol)) message,
The address allocation device according to claim 1, wherein the address allocation device is a DHCP (Dynamic Host Configuration Protocol) server. When the communication protocol between the information processing device and the address assignment device is IPv6 (Internet Protocol Version 6) and ICMPv6 is used for setting the default gateway of the information processing device,
The address change information is a link-layer address change message of ICMPv6 Neighbor advertisement,
The address assignment device is a DHCP (Dynamic Host Configuration Protocol) server,
The network setting information transmission unit
3. The selected address assignment device is instructed to execute an ICMPv6 Router advertisement from a router serving as a default gateway of a site to which the address assignment device belongs to the information processing device. Address assignment device. A communication system having a plurality of address assignment devices for transmitting network setting information including an address of a default gateway to be passed when the information processing device performs data communication to the information processing device,
Each of the address allocation devices is
An address change information transmission unit for transmitting address change information for changing the address information of the address assignment device held by the information processing device to the information processing device;
A message processing unit that receives a response message of the message after transmitting the message to the information processing apparatus;
A response time measuring unit that measures a response time that is a time from transmission of the message to reception of a response message of the message;
A storage unit for storing inter-device transfer order information indicating a transfer order of transfer information between address allocation devices in the same network segment;
A data transfer unit that transfers the transfer information to which the measured response time and the network setting information are added to the next address allocation device indicated in the inter-device transfer order information;
The address allocation device with the last transfer order is:
Receiving the transfer information from another address allocation device, referring to the response time of its own address allocation device and the response time of each of the other address allocation devices indicated in the received transfer information, A device selection unit for selecting a short address assignment device;
A communication system, further comprising: a network setting information transmitting unit that transmits network setting information of the selected address assignment device to the information processing device. A management method executed by an address assignment device that transmits network setting information including an address of a default gateway to be passed when an information processing device performs data communication, to the information processing device,
An address change information transmission step for transmitting address change information for changing the address information of the address allocation device held by the information processing device to the information processing device;
A message processing step of receiving a response message of the message after transmitting the message to the information processing apparatus;
A response time measuring step for measuring a response time which is a time from transmission of the message to reception of the response message of the message;
The next address assignment device indicated by the inter-device transfer order information indicating the transfer order of the transfer information between the address assignment devices in the same network segment , with the transfer information added with the measured response time and the network setting information. A data transfer step to transfer to,
When its own address allocation device is the last address allocation device indicated in the inter-device transfer order information, it receives the transfer information from another address allocation device, and receives the response time of its own address allocation device and the received A device selection step of referring to the response time of each of the other address allocation devices indicated in the transfer information and selecting the address allocation device with the shortest response time;
A network setting information transmitting step of transmitting network setting information of the selected address assignment device to the information processing device. To the address assignment device that transmits network setting information indicating the address of the default gateway to be passed when the information processing device performs data communication to the information processing device,
An address change information transmission step for transmitting address change information for changing the address information of the address allocation device held by the information processing device to the information processing device;
A message processing step of receiving a response message of the message after transmitting the message to the information processing apparatus;
A response time measuring step for measuring a response time which is a time from transmission of the message to reception of the response message of the message;
The next address assignment device indicated by the inter-device transfer order information indicating the transfer order of the transfer information between the address assignment devices in the same network segment , with the transfer information added with the measured response time and the network setting information. A data transfer step to transfer to,
When its own address allocation device is the last address allocation device indicated in the inter-device transfer order information, it receives the transfer information from another address allocation device, and receives the response time of its own address allocation device and the received A device selection step of referring to the response time of each of the other address allocation devices indicated in the transfer information and selecting the address allocation device with the shortest response time;
A management program for executing a network setting information transmission step of transmitting network setting information of the selected address assignment device to the information processing device.

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