KR20180126868A - Method for providing dualization - Google Patents

Abstract

According to an embodiment of the present invention, a dualization providing method which is performed by a software defined network (SDN) controller connected to an SDN network, comprising the steps of: detecting whether a fault occurs in a first virtual machine when the first virtual machine allocated with a first private IP provides a service for a terminal located outside an SDN; issuing a command to a second virtual machine allocated with a second private IP to start an operation thereof when the fault occurrence is detected; and controlling a virtual router which transmits traffic transmitted from an external terminal to the first virtual machine before the fault occurs, to transmit the same to the second virtual machine after the operation of the second virtual machine is started.

Description

{METHOD FOR PROVIDING DUALIZATION}

The present invention relates to a method for providing redundancy. More specifically, a second virtual machine providing the same service as a first virtual machine in which a failure occurs is generated or operated by a software defined network controller (SDN controller) after detection of occurrence of the failure. ≪ RTI ID = 0.0 >

A service provider that provides various services using a server uses a dualization technique to stably provide the service. Examples of services requiring redundancy include a mobile communication service providing voice or data, a banking service, a web portal service, a messenger service, or a game service.

Here, a mobile communication service or banking service that provides voice or data may have a very high level of disaster recovery (such as level 6 (6 nines availability (99.9999%)) or level 5 (5 nines availability (99.999% failover is required. That is, in case of the service, if the server in the active state fails, the same service can be provided by the server in the standby state within several to several tens ms.

FIGS. 1A and 1B are diagrams illustrating a redundancy providing method for a service requiring such a high level of failure recovery. Referring to FIG. 1A, a first server 2 refers to a server that provides an IP with an IP of 10.1.1.2. The second server 3 is a server in a standby state, and indicates a server that is currently in a standby state without providing a service. The first server (2) and the second server (3) synchronize the main information. The second server 3 checks whether the first server 2 is operating normally, for example, by a heartbeat check method. As a result of the check, if a failure occurs in the first server 2, the second server 3 immediately substitutes the first server 2 (within the time required at the level 5 or 6) And provide the corresponding service.

However, as shown in Figs. 1A and 1B, the above-mentioned high level of failure recovery must be configured so that the following conditions are satisfied. First, the network configuration of the second server 3 should be the same as that of the first server 2. For example, the second server 3 should be connected to the same switch 1 as the first server 2. Second, the second server 2 must be in constant operation even if it is in the standby state. The second server 3 can provide the same service as that provided by the first server 2 within the time required at the level 5 or 6 when the first server 2 fails.

Korean Unexamined Patent Publication No. 10-2015-0111608 (published October 10, 2015)

Among the services requiring redundancy, there is a service that requires a relatively low failure recovery than the one described above. For example, level 4 (4 nines availability (99.99%)) level is required for web portal service, messenger service or game service.

Accordingly, a problem to be solved by the present invention is that the above-described conditions (same as the network configuration between the standby server and the actis server, and the standby operation of the standby server) are satisfied for a service requiring a relatively low level of failure recovery than the level 5 or 6, To provide redundancy without having to satisfy the requirements of the present invention.

A duplication providing method performed by an SDN controller connected to a software defined network (SDN) according to an exemplary embodiment of the present invention includes providing a service to a terminal located outside the software defined network and allocating a first private IP The method comprising the steps of: detecting whether a failure has occurred in a virtual machine; instructing a second virtual machine, to which a second private IP is allocated, to operate when the occurrence of the failure is detected; And requesting a virtual router for delivering traffic to the first virtual machine to forward the traffic delivered from the external terminal to the second virtual machine after the operation of the second virtual machine is started.

According to one embodiment, the server in the standby state for redundancy may be connected to a different switch from the server in the actuated state. Thus, flexibility in system configuration for redundancy can be increased. Also, the standby server does not have to be operated at all times. For example, the standby server may be created and started to operate after a failure occurs in the active server. Therefore, a waste of resources due to the normal operation of the standby server may not occur any more.

Figures 1a and 1b show a diagram of a system for providing redundancy for services requiring level 5 or 6 failover.
2 is a diagram illustrating a system for providing redundancy in accordance with one embodiment.
3 is a flowchart illustrating a method of providing a redundancy according to an embodiment of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention, and the manner of achieving them, will be apparent from and elucidated with reference to the embodiments described hereinafter in conjunction with the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. To fully disclose the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims.

In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear. The following terms are defined in consideration of the functions in the embodiments of the present invention, which may vary depending on the intention of the user, the intention or the custom of the operator. Therefore, the definition should be based on the contents throughout this specification.

2, the system 100 includes a duplication control apparatus 100, a terminal 200, a virtual router 300, a first virtual machine 410 and a first switch 411 connected to the first virtual machine 410, (420) and a second switch (421) connected thereto. In addition, these components are connectable by the network 500.

At this time, the redundancy control apparatus 100, the virtual router 300, the first virtual machine 410 and the first switch 411 connected thereto, and the second virtual machine 420 and the second switch 421 connected thereto May logically be interconnected within a software defined network and the terminal 200 may be logically connected to a network (wired network or wireless network) that is placed outside of such a software defined network and is typically used .

The first virtual machine 410 and the second virtual machine 420 are each implemented in a virtualization server created according to a virtualization technique of a plurality of physical servers. The first virtual machine 410 and the second virtual machine 420 can each independently provide a specific service together with another virtual machine or the like. For example, the first virtual machine 410 and the second virtual machine 420 according to an embodiment may provide a web portal service, a messenger service, or a game service.

The first virtual machine 410 is assigned a first private IP. The first private IP can only be used or recognized internally in the software defined network and can not be recognized by objects located outside the software defined network, The second virtual machine 420 is assigned a second private IP. The second private IP can only be used or recognized internally in the software defined network and can not be recognized by objects located outside the software defined network, At this time, the first private IP is an IP different from the second private IP.

The first virtual machine 410 is connected to the network 500 via the first switch 411. The first switch 411 is a virtual switch that is implemented in software within the first virtual machine 410 and is a virtual switch that is provided on the path when the first virtual machine 410 communicates with the external terminal 200 . The first switch 411 transmits the failure of the first virtual machine 410 to the SDN controller 120.

The second virtual machine 420 is connected to the network 500 via the second switch 421. The second switch 421 is a virtual switch implemented in software in the second virtual machine 420 and is a virtual switch that is provided on the path when the second virtual machine 420 communicates with the external terminal 200 . The second switch 421 transfers the failure of the second virtual machine 420 to the SDN controller 120.

Here, the first virtual machine 410 is connected to the first switch 411 while the second virtual machine 420 is connected to the second switch 421. That is, the respective switches connected to the first virtual machine 410 and the second virtual machine 420 are different from each other.

The virtual router 300 serves as a gateway for connecting the first virtual machine 410 or the second virtual machine 420 to the external terminal 200. [ This virtual router 300 can be implemented and controlled by a software defined network.

The virtual router 300 has a public IP address, and informs other routers to route the public IP address to the virtual router 300 itself.

The virtual router 300 stores mapping information for mapping the public IP with the first private IP. When the first virtual machine 410 having the first private IP transmits traffic to the virtual router 300 with the destination of the external terminal 200 as a destination, the virtual router 300 uses the mapping information So that the traffic is delivered to the external terminal 200. To this end, the virtual router 300 converts the first private IP to the public IP using the mapping information. When the external terminal transmits the traffic to the virtual router 300 using the public IP as the destination IP, the virtual router 300 transmits the corresponding traffic to the first virtual terminal 410 using the mapping information. To this end, the virtual router 300 converts the public IP into the first private IP using the mapping information.

The mapping information stored in the virtual router 300 is changeable. For example, the virtual router 300 can receive an instruction to change the private IP mapped to the public IP from the open stack 110 from the first private IP to the second private IP, thereby changing the mapping information accordingly.

The terminal 200 may be a terminal receiving various services provided by a software defined network. For example, it may be a smart phone, a smart pad, a PC, a PDA, or the like.

The terminal 200 can acquire information on the public IP assigned to each of the above-described services. If the acquired public IP is matched with the public IP of the virtual router 300, the terminal 200 can receive the service from the virtual machine connected to the virtual router 300 through the virtual router 300.

Here, since the terminal 200 is disposed outside the software defined network as described above, it can not obtain the first private IP and the second private IP that can be used / recognized only in the software defined network. The terminal 200 can only acquire information on the public IP assigned to the virtual router 300. [

The duplication control apparatus 100 detects whether a failure occurs in an active virtual machine providing a service and controls the other virtual machine to provide the corresponding service when a failure occurs. That is, the duplication control apparatus 100 provides a function of redundancy. Hereinafter, the configuration of the duplication control apparatus 100 will be described.

The duplication control apparatus 100 includes an open stack 110 and a software defined network controller 120. This duplication control apparatus 100 can be implemented by a memory including an instruction programmed to perform a function to be described later and a microprocessor for executing such an instruction.

First, the open stack 110 is an open source cloud technology, which is a type of virtualization OS installed in a network function virtualization infrastructure (NFVI), although it is not shown in the drawing. A detailed description of the configuration of the open stack 110 itself will be omitted.

The open stack 110 creates, modifies, and deletes virtual machines. For example, the first virtual machine 410 and the second virtual machine 420 shown in FIG. 2 are generated by the open stack 110.

The open stack 110 requests the virtual router 300 to map the public IP and the private IP. To this end, the open stack 110 transmits information on the private IP to the virtual router 300. Accordingly, mapping information on the private IP mapped to the public IP is generated and stored in the virtual router 300.

The open stack 110 requests the SDN controller 120 to set the network according to the mapping relationship between the public IP and the private IP. In this case, the network is set according to the mapping relationship between the public IP and the private IP. Accordingly, when the first virtual machine 410 having the first private IP transmits traffic to the virtual router 300 with the external terminal 200 as a destination, the traffic is delivered to the external terminal 200 . Also, if the external terminal 200 transmits the traffic to the virtual router 300 using the public IP as the destination IP, the corresponding traffic can be delivered to the first virtual terminal 410.

The SDN controller 120 monitors the virtual machine in the active state. Specifically, the SDN controller 120 receives information on whether a failure has occurred in the virtual machine from a switch connected to the virtual machine in an active state, and determines whether the virtual machine has failed based on the received information. In the case of FIG. 2, the SDN controller 120 receives the status of the first virtual machine 410 in an active state from the first switch 411, and monitors the failure.

The SDN controller 120 informs the open stack 110 of the occurrence of the failure when a failure is detected in the virtual machine in the active state. In addition, when a failure is detected, the SDN controller 120 requests the open stack 110 to start the creation or operation of a virtual machine in a standby state. Thereby allowing the open stack 110 to create or operate a virtual machine that is in a standby state. 2, the SDN controller 120 transmits the fault occurrence of the first virtual machine 410 in an active state to the open stack 110 and informs the open stack 110 of the occurrence of the second virtual machine 420 Or the start of operation.

That is, according to one embodiment, when a failure occurs in a virtual machine that is in an active state, a virtual machine that is in a standby state is created or started after that. Therefore, since the virtual machine in the standby state does not need to be operated at all times, resource waste due to normal operation can be eliminated. In this case, the time required until the service is restarted by the second virtual machine after the service is stopped due to the failure of the first virtual machine can satisfy the criterion required at the level 4.

In addition, a virtual machine in a standby state and a virtual machine in an active state need not be connected to the same switch. Thus, flexibility can be provided in constructing a system that provides redundancy.

3 is a flowchart illustrating a method of providing a redundancy according to an embodiment of the present invention. The duplication providing method shown in FIG. 3 can be performed by the SDN controller 110 shown in FIG. In addition, the procedure shown in FIG. 3 is merely an example, and thus the spirit of the present invention is not limited thereto.

3, the physical switch 310 is a configuration that is associated with the virtual router 300 and serves as a gateway to the first virtual machine 410 and the second virtual machine 420, Quot; switch "

Referring to FIG. 3, first, the open stack 110 instructs the first virtual machine 410 to provide a service to the terminal 200 in an active state, that is, to start an operation (SlOO). The first virtual machine 410 at this time may be previously generated by the open stack 110.

Next, the failure of the first virtual machine 410 in the active state is reported to the SDN controller 110 (S110). More specifically, such a report may be periodically performed by the first switch 411 implemented in the first virtual machine 410 or when a failure occurs.

Next, the open stack 110 requests the virtual router 300 to map the public IP and the private IP (S120). To this end, the open stack 110 transmits information on the private IP to be mapped to the public IP to the virtual router 300. Accordingly, mapping information on the private IP mapped to the public IP is generated and stored in the virtual router 300.

Next, the open stack 110 requests the SDN controller 120 to set the network according to the mapping relationship between the public IP and the private IP (S130). In response to the request from the open stack 110, the SDN controller 120 sets a physical switch so that the network is set according to the mapping relationship between the public IP and the private IP (S140).

The service is provided by the first virtual machine 410. In detail, the external terminal 200 requests the service and transmits the traffic to the virtual router 300 using the public IP as the destination IP (S210). The virtual router 300 converts the public IP into the first private IP address assigned to the first virtual machine 410 using the mapping information and then transmits the converted information of the first private IP to the physical switch 310 (S220). The physical switch 310 transmits the traffic to the first virtual machine 410 having the first private IP (S230). The physical switch 310 from the physical switch 310 to the virtual router 300 in step S250 and the virtual router 250 from the terminal 200 in the reverse order, that is, in the first virtual machine 410, (S260).

Meanwhile, while the service is provided by the first virtual machine 410, the first virtual machine 410 may fail (S300). Then, the first switch 411 connected to the first virtual machine 410 reports the failure occurrence to the SDN controller 110 (S310). The SDN controller 110 reports the failure to the open stack 120 and requests the virtual machine in the standby state, e.g., the second virtual machine 420, to start the operation (S320).

The open stack 110 creates a second virtual machine 420 using a server having idle resources among the current servers and then transmits the same service as that provided by the first virtual machine 410 to the second virtual machine 420. [ (Step S330). Alternatively, the open stack 110 may instruct the second virtual machine 420, which has already been created, to start the operation of the second virtual machine 420 so as to provide the same service as that provided by the first virtual machine 410 You may.

Next, the failure of the second virtual machine 420 is monitored by the SDN controller 110 (S340). More specifically, this monitoring can be performed periodically or when a failure occurs by the second switch 412 implemented in software in the second virtual machine 420.

Next, the open stack 110 requests the virtual router 300 to map the public IP and the second private IP (S350). To this end, the open stack 110 transmits information on the private IP to be mapped to the public IP, that is, information on the second private IP to the virtual router 300. Accordingly, the mapping information stored in the virtual router 300 is changed and stored.

Next, the open stack 110 requests the SDN controller 120 to set the network according to the mapping relationship between the public IP and the second private IP (S360). In response to the request from the open stack 110, the SDN controller 120 sets up the physical switch so that the network is set according to the mapping relationship between the public IP and the second private IP (S370).

Thereafter, the service is provided by the second virtual machine 420, for example, after the second virtual machine 420 starts operation (S400). Specifically, when the external terminal 200 requests the service while transmitting the traffic to the virtual router 300 using the public IP as the destination IP, the virtual router 300 transmits the public IP to the virtual router 300 using the mapping information. 2 private IP, and transmits information on the converted second private IP together with the traffic to the physical switch 310. The physical switch 310 transmits the traffic to the second virtual machine 420 having the second private IP. The second virtual machine 420 responds to the physical switch 310 with respect to the transmitted traffic and the physical switch 310 responds to the virtual router 300. The virtual router 300 transmits the response to the terminal 200 ).

Thus, according to one embodiment, a virtual machine that is in a standby state is created or started after a failure occurs in the active virtual machine. Therefore, since the virtual machine in the standby state does not need to be operated at all times, resource waste due to normal operation can be eliminated.

In addition, a virtual machine in a standby state and a virtual machine in an active state need not be connected to the same switch. Thus, flexibility can be provided in constructing a system that provides redundancy.

On the other hand, the duplication providing method described above can be implemented in the form of a computer program stored in a computer-readable recording medium that is programmed to perform the procedures included in the method, or a computer program programmed to perform the procedures included in the method And a computer-readable recording medium storing the program.

Combinations of each step of the flowchart and each block of the block diagrams appended to the present invention may be performed by computer program instructions. These computer program instructions may be loaded into a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus so that the instructions, which may be executed by a processor of a computer or other programmable data processing apparatus, And means for performing the functions described in each step are created. These computer program instructions may also be stored in a computer usable or computer readable memory capable of directing a computer or other programmable data processing apparatus to implement the functionality in a particular manner so that the computer usable or computer readable memory It is also possible for the instructions stored in the block diagram to produce a manufacturing item containing instruction means for performing the functions described in each block or flowchart of the block diagram. Computer program instructions may also be stored on a computer or other programmable data processing equipment so that a series of operating steps may be performed on a computer or other programmable data processing equipment to create a computer- It is also possible that the instructions that perform the processing equipment provide the steps for executing the functions described in each block of the block diagram and at each step of the flowchart.

Also, each block or each step may represent a module, segment, or portion of code that includes one or more executable instructions for executing the specified logical function (s). It should also be noted that in some alternative embodiments, the functions mentioned in the blocks or steps may occur out of order. For example, two blocks or steps shown in succession may in fact be performed substantially concurrently, or the blocks or steps may sometimes be performed in reverse order according to the corresponding function.

The above description is merely illustrative of the technical idea of the present invention, and various modifications and changes may be made by those skilled in the art without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the scope of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The scope of protection of the present invention should be construed according to the following claims, and all technical ideas within the scope of equivalents should be construed as falling within the scope of the present invention.

According to one embodiment, since the virtual machine in the standby state does not need to be operated at all times, resource waste due to normal operation can be eliminated.

Flexibility can also be provided in constructing a system that provides redundancy.

100: Redundant device
110: Open stack
120: SDN controller
200: terminal
300: Virtual Router

Claims (4)

A duplication providing method performed by an SDN controller connected to a software defined network (SDN), wherein when a first virtual machine to which a first private IP is allocated provides a service to a terminal located outside the software defined network ,
Detecting whether the first virtual machine has failed;
When the occurrence of the failure is detected, instructing a second virtual machine assigned a second private IP to start operation;
Wherein the second virtual machine is configured to transmit the traffic from the external terminal to the first virtual machine before the occurrence of the failure, To the machine,
Providing redundancy. The method according to claim 1,
Wherein the second virtual machine comprises:
Is generated by an open stack connected to the SDN according to the command,
Providing redundancy. The method according to claim 1,
Wherein the switch on the path where the first virtual machine is connected to the external terminal is different from the switch on the path where the second virtual machine is connected to the external terminal
Providing redundancy. The method according to claim 1,
The time when the provision of the service is stopped to the external terminal according to the occurrence of the failure satisfies the availability of the level 4
Providing redundancy.

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