WO2016192282A1

WO2016192282A1 - Link detection method and device

Info

Publication number: WO2016192282A1
Application number: PCT/CN2015/092858
Authority: WO
Inventors: 谌玉华
Original assignee: 中兴通讯股份有限公司
Priority date: 2015-06-03
Filing date: 2015-10-26
Publication date: 2016-12-08
Also published as: CN106301986A

Abstract

Disclosed is a link detection method. The method comprises the following steps: if a bidirectional forwarding detection (BFD) protocol negotiation between a first terminal and a second terminal is successful, generating, by the second terminal, a first BFD packet, and regularly sending the first BFD packet to the first terminal; if the second terminal does not receive a second BFD packet fed back by the first terminal and based on the first BFD packet, and the number for the second terminal to send the first BFD packet is greater than or equal to a preset threshold, determining, by the second terminal, that a link thereof between the first terminal has a fault. Also disclosed is a link detection device. The present invention can improve a reliability of a BFD detection mechanism.

Description

Link detection method and device

Technical field

The present invention relates to the field of data communication technologies, and in particular, to a link detection method and apparatus.

Background technique

Bidirectional Forwarding Detection (BFD) is a set of international standard protocols for fast detection. It provides a light load and continuous time period detection. Compared with other detection mechanisms in the past, it has many unique advantages. The BFD session detection is performed in two steps. The CPU then initiates a BFD session to negotiate. If the negotiation succeeds, the CPU configures the session to be created by the hardware. The final BFD packet is transmitted by the hardware.

When the negotiation is successful, a BFD session is created at both ends. However, the creation of the BFD session is not possible. For example, after the first negotiation succeeds, the device will notify the hardware to configure a BFD session. One end is configured to receive the negotiation success packet and the other end is in the negotiation. If the configuration is successful, there will be a certain delay when creating BFD at both ends. If the one end of the configuration is not received, the device will issue a Down alarm, which may cause a switchover that should not occur. The switchover is performed because the packets received at both ends are not synchronized. The link to the main link is incorrect, and the protection link is enabled to transmit data.

After the BFD session is configured to be in the hardware, the hardware detects whether the link is correct, such as the time in the BFD packet. In the normal scenario, this negotiation to session creation and verification can be processed quickly. However, in a large-capacity scenario, once the active link session is created successfully, a large number of protocols are in action, and the CPU is configured to process too much software interface information, so that the CPU cannot process the BFD packets to be sent in time. The session of the BFD session that is in the INIT or the UP state is returned to the Down state due to the timeout. For example, in the HSB (Hot-standby) switchback, if a physical port has many TE-LSPs, it corresponds to a large number of BFD sessions. The BFD packet is not processed in a timely manner. The switchback is performed when the protection link is enabled to transmit data. The main link is detected to be normal and needs to be returned to the primary link for transmission. Therefore, the traditional BFD detection mechanism is unreliable.

Summary of the invention

The embodiment of the invention provides a link detection method and device, which aims to improve the reliability of the BFD detection mechanism at least.

A method for detecting a link according to an embodiment of the present invention, the method includes the following steps: after the BFD protocol negotiation between the first terminal and the second terminal is successful, the second terminal generates a first BFD report. And sending the first BFD packet to the first terminal, and the second terminal does not receive the second BFD packet that is sent by the first terminal based on the first BFD packet, and When the number of times that the second terminal sends the first BFD packet is greater than or equal to a preset threshold, the second terminal determines that the link between the first terminal and the first terminal is faulty.

After the step of determining that the link between the second terminal and the first terminal is faulty, the second terminal sends a fault alarm message and stops sending BFD packets.

The method further includes: receiving, by the second terminal, a second BFD packet that is sent by the first terminal based on the first BFD packet, and the second terminal sending the first BFD packet When the number of times is less than a preset threshold, the second terminal determines that the link between the second terminal and the first terminal is normal.

Receiving, by the second terminal, the second BFD packet that is sent by the first terminal based on the first BFD packet, and the number of times that the second terminal sends the first BFD packet is less than a preset And the step of determining, by the second terminal, that the link between the first terminal and the first terminal is normal, the second terminal, when receiving the second BFD packet that is fed back by the first terminal according to the first BFD packet And determining, by the first terminal, whether the second BFD packet is a keep-alive packet; if the second BFD packet is a keep-alive packet, verifying the second BFD packet, if the verification succeeds And the second terminal determines that the link between the second terminal and the first terminal is normal.

The step of determining whether the second BFD packet fed back by the first terminal is a keep-alive packet includes: calculating, according to a period of the second BFD packet fed back by the first terminal, the second terminal The feedback time interval of each BFD packet fed back by the terminal; the second terminal determines whether the feedback time interval of each BFD packet fed back by the first terminal is less than a preset time; if the judgment result is the feedback of the first terminal When the feedback interval of each BFD packet is less than the preset time, the second BFD packet is determined to be a keep-alive packet.

In addition, in order to achieve at least the above object, the embodiment of the present invention further provides a link detecting apparatus, where the apparatus includes: a generating module, configured to generate a first BFD report after the first terminal and the second terminal BFD protocol negotiate successfully. The sending module is configured to periodically send the first BFD packet to the first terminal, and the receiving module is configured to receive the second BFD packet that is sent by the first terminal based on the first BFD packet; a determining module, configured to: in the second terminal, not receiving the second BFD packet that is sent by the first terminal based on the first BFD packet, and the second terminal sending the first BFD packet When the number of times is greater than or equal to the preset threshold, it is determined that the link between the second terminal and the first terminal is faulty.

The device further includes: an alarm module, configured to generate a fault alarm message when the BFD link fails.

The determining module is further configured to: receive, by the second terminal, a second BFD packet that is sent by the first terminal based on the first BFD packet, and the second terminal sends the first BFD packet When the number of times is less than or equal to the preset threshold, it is determined that the link between the second terminal and the first terminal is normal.

The determining module includes: a determining unit and a verifying unit, where the determining unit is configured to determine that the first terminal feedbacks when receiving the second BFD packet that is fed back by the first terminal according to the first BFD packet Whether the second BFD packet is a keep-alive packet; the verification unit is configured to: when the determining result of the determining unit is that the second BFD packet is a keep-alive packet, the second BFD packet Verification is performed, and if the verification is passed, it is determined that the link between the second terminal and the first terminal is normal.

The determining unit includes a calculating subunit, a determining subunit, and a determining subunit, and the calculating subunit is configured to calculate each BFD report fed back by the first terminal based on a period of the second BFD packet fed back by the first terminal a time interval of the text; the determining subunit is configured to determine whether a feedback time interval of each BFD message fed back by the first terminal is less than a preset time; the determining subunit is configured to determine a result in the determining subunit Each of the said feedback for the first terminal When the feedback interval of the BFD packet is less than the preset time, the BFD packet is determined to be a keep-alive packet.

In the embodiment of the present invention, after the first terminal and the second terminal BFD protocol are successfully negotiated, the second terminal generates a first BFD packet, and periodically sends the first BFD packet to the first terminal; The second terminal does not receive the second BFD packet that is sent by the first terminal based on the first BFD packet, and the number of times that the second terminal sends the first BFD packet is greater than or equal to a preset threshold. The second terminal determines that the link between the first terminal and the first terminal has failed. In the above manner, after the negotiation succeeds, the second terminal in the embodiment of the present invention continues to send the preset number of BFD packets without waiting for the BFD packet sent by the first terminal, and then determining the BFD packet after the preset threshold BFD packet is sent. The second terminal determines that the link between the first terminal and the first terminal has failed. It is possible to avoid unnecessary switching caused by the first terminal and the second terminal being unsynchronized, and to improve the negotiation of the INIT due to the failure of the first terminal CPU to process the BFD packet that needs to be sent in time in the large-capacity scenario. The technical problem that the BFD link in the UP state returns to the Down state due to timeout, thereby improving the reliability of the BFD detection mechanism.

DRAWINGS

1 is a schematic flowchart of a first embodiment of a link detecting method according to the present invention;

2 is a schematic flowchart of a second embodiment of a link detecting method according to the present invention;

3 is a second BFD packet that the first terminal receives based on the first BFD packet, and the second terminal sends the first BFD packet in the second terminal in FIG. When the number of times is less than the preset threshold, the second terminal determines a refinement flow chart of the step that the link between the second terminal and the first terminal is normal;

4 is a schematic diagram of functional modules of a first embodiment of a link detecting apparatus according to the present invention;

FIG. 5 is a schematic diagram of a refinement function module of the judging module in FIG. 4; FIG.

FIG. 6 is a schematic diagram of a refinement function module of the judging unit in FIG. 5. FIG.

The implementation, functional features, and advantages of the present invention will be further described in conjunction with the embodiments.

detailed description

It is understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

The embodiment of the invention provides a link detection method.

Please refer to FIG. 1. FIG. 1 is a schematic flowchart diagram of a first embodiment of a link detecting method according to the present invention.

In this embodiment, the link detection method of the present invention includes:

Step S10, after the first terminal and the second terminal BFD protocol are successfully negotiated, the second terminal generates a first BFD packet, and periodically sends the first BFD packet to the first terminal.

In the network data transmission, the BFD packet is set to the authentication parameter for the BFD session. Before the BFD session is established, the BFD session is in the Down state. The BFD session is set to be the BFD session. The BFD session is reported to the CPU. After the BFD session is established, the BFD session is set to update the BFD session parameters, or the BFD session is renegotiated. After the BFD session is established, the BFD session is set to the Up state. The text is a keep-alive message, which is mainly processed by a Field-Programmable Gate Array (FPGA). The time and port parameters included in the BFD packet need to be reported to the CPU for processing. In the traditional BFD detection mechanism, if the CPU fails to process in time due to task scheduling, it will cause a large number of packets in the CPU to accumulate, affecting the stability of the entire BFD operation and reducing the performance of the entire system. For example, the second terminal receives the pre-configured two-way. After forwarding the negotiation packet sent by the first terminal of the BFD protocol, the first terminal cannot process the negotiation packet and configure the hardware to send the BFD packet, so that the second terminal does not receive the message for a long time. In the BFD packet, the second terminal and/or the first terminal considers that the primary BFD link is faulty, and then switches to the standby BFD session link or sends a BFD fault packet.

When the data transmission needs to be started, the first terminal actively sends a BFD negotiation packet to the second terminal that is configured with the BFD protocol. When receiving the BFD negotiation packet sent by the first terminal, the second terminal verifies the BFD negotiation packet sent by the first terminal, and after the verification is passed, the second terminal configures the hardware field editable gate array FPGA to create a BFD session to generate a BFD session. The BFD packet is sent to the first terminal, and the BFD packet is sent to the first terminal when the field editable gate array FPGA generates a BFD packet, or the negotiation packet is verified. Sending the generated negotiation success message to the first terminal, and then sending the BFD packet generated by the field editable gate array FPGA to the first terminal, of course, the second terminal may also send P set or F set The bit message is sent to the first terminal. In a specific implementation, the received BFD negotiation packet sent by the first terminal and the BFD packet generated by the second terminal are sent together. At this time, the first terminal CPU may be occupied. If the first terminal is occupied, the first terminal hardware field editable gate array FPGA receives the negotiation success message or the pre-sent message sent by the second terminal based on the negotiation message sent by the first terminal. Set the number of BFD packets.

When the first terminal CPU is not occupied, the first terminal receives the BFD negotiation success message or the BFD message, and the first terminal CPU obtains the BFD negotiation success message or the BFD keep-alive message according to the received BFD negotiation message. Configuring a hardware field editable gate array FPGA to establish a BFD session to generate a BFD packet and send the BFD packet to the second terminal, and of course, the received BFD packet sent by the second terminal and the BFD report generated by the first terminal. The text is sent to the second terminal together. In the specific implementation, the first terminal can also automatically create a BFD session after the hardware field editable gate array FPGA receives the BFD negotiation success message.

For example, in this embodiment, when the second terminal receives the negotiated BFD packet sent by the first terminal, the second terminal verifies the negotiation BFD packet sent by the first terminal, and if the verification succeeds, the negotiation succeeds to the first terminal. The BFD packet is sent to the second terminal in the hardware field to edit the gate array FPGA to configure the BFD session. The hardware field editable gate array FPGA configures the BFD session to count the generated BFD keep-alive packets, and sends the generated BFD packets to the first terminal once after generating the BFD packets. Of course, it can also be set to 2 times and 4 times. In the specific implementation, the setting menu can also be entered, and the preset number of times is set for the user with different performances of the device. In more implementations, When a BFD session is set, the BFD packet can be sent according to the traditional mechanism. After the BFD session is successfully sent, a BFD packet is sent to the first terminal. The first terminal is received before the preset number of BFD packets are sent. Sending a corresponding keep-alive message and/or a P-set message, but not detecting the BFD packet and/or the P-set packet sent by the first terminal, that is, before sending the preset number of BFD packets. The second terminal does not receive the BFD packet of the first terminal, and does not generate an alarm or enable other protection mechanisms, such as enabling the protection link. When the second terminal receives the preset number of BFD packets sent by the first terminal, the preset number of keep-alive messages are reported to the CPU of the second terminal.

When the first terminal receives the successfully negotiated packet, the first terminal CPU verifies the received negotiation success packet, and if the verification succeeds, notifies the first terminal hardware to edit the gate array FPGA to configure the BFD. Session, at this time, the first terminal starts to enter the UP state, and the hardware field can edit the gate array FPGA to configure the BFD session, generate BFD keep-alive packets, and count the generated BFD packets. After generating 3 BFD packets, Sending the generated three BFD packets to the second terminal, which may be set to 2 times or 4 times, of course, may also enter a setting menu, for different performances of the first terminal and/or the second terminal. Define settings. In a specific implementation, after the BFD session is entered, the BFD packet can be sent in the BFD session according to the traditional mechanism. After receiving the BPDU, the BFD packet is sent to the device. The second terminal receives a corresponding keep-alive message and/or a P-set message sent by the second terminal. When a preset number of BFD packets are received, the preset number of keep-alive messages are reported to the CPU of the first terminal. In a further implementation, after the first terminal sends the negotiation message, the hardware field editable gate array FPGA is notified to configure the BFD session. It is known in the art that the time taken to send BFD keep-alive packets is less than the preset time for detecting BFD packets in the BFD detection mechanism. For example, the preset time in the BFD detection mechanism is 5 seconds. If it is not received within 5 seconds, If the BFD session is faulty, the BFD session is faulty. The time taken for the number of BFD keepalive packets is less than 5 seconds. In the specific implementation, the preset time in the BFD detection mechanism can be adjusted.

After the preset number of BFD messages are sent, the process proceeds to step S20.

In step S20, the second terminal does not receive the second BFD packet that is sent by the first terminal based on the first BFD packet, and the second terminal sends the first BFD packet more than When the threshold is equal to or equal to the preset threshold, the second terminal determines that the link between the first terminal and the first terminal is faulty.

In the step S10, when the number of times the second terminal sends the BFD packet to the first terminal is greater than or equal to a preset threshold, for example, in this embodiment, the first terminal CPU is occupied, and the received terminal cannot be processed in time. After the BFD packet sent by the second terminal is not processed in time after receiving the negotiation success message sent by the second terminal, the hardware editable gate array FPGA cannot be configured to generate the BFD packet, and the second terminal is in the second terminal. Determining, by the second terminal, the second terminal and the first terminal, if the number of times the BFD packet is sent by the terminal is greater than or equal to 3 times, if the second terminal does not receive the BFD packet sent by the first terminal The link between the links has failed. Of course, if the second terminal receives the BFD packet sent by the first terminal in the time that the second terminal sends the BFD packet of the preset threshold, but the verification fails, the foregoing may also be determined. The link between the second terminal and the first terminal fails. In a specific implementation, after the second terminal sends the preset number of times of the BFD packet, if the second terminal does not receive the BFD packet sent by the first terminal, the protection link is enabled for data transmission, and then And sending the BFD packet with the preset threshold number, if the BFD packet of the preset threshold is sent after the protection link is sent, the second terminal is determined to be the same as the feedback BFD packet of the first terminal. The link between the first terminal and the first terminal fails.

Or, if the second terminal CPU is occupied, the received BFD packet sent by the first terminal cannot be processed, and after the first terminal sends the BFD packet with the preset threshold, if the first terminal does not receive the When the BFD packet sent by the second terminal is used, it is determined that the link between the second terminal and the first terminal is faulty, and then the first terminal automatically resends the BFD packet, and may not be sent.

Step S30: The second terminal generates a fault alarm message and sends it to the CPU, and stops sending BFD packets.

According to the result of the step S20, if it is determined that the BFD session link is faulty, the first terminal and/or the second terminal generate a fault alarm message, and send a fault alarm message to the respective terminal CPU. The fault alarm packet can be sent to the peer end. In the specific implementation, the fault alarm packet can be sent according to the preset frequency, or only the fault alarm packet can be sent only before the fault state is changed, so as to reduce the fault alarm message to the CPU. The burden may of course not be sent. For example, the first terminal resends the negotiation message to the second terminal through the CPU. The CPU receives the fault alarm packet and searches for the BFD information table. The preset BFD information table stores a BFD information index table, which mainly involves communication problems between the BFD packet and the BFD link. When the BFD link is faulty, the corresponding fault alarm packet is found and the corresponding problem is processed. In a further implementation, the preset BFD information table may be used to determine whether there is a preset stop flag in the BFD packet, and if it is determined that there is a stop flag in the BFD packet, the fault alarm report is If the stop flag in the preset BFD information table is found, the BFD packet is stopped.

In another implementation, by determining the number of CPU processes, it is determined according to the determination result whether the BFD packet is sent by the preset number of times. Because the task behavior of the CPU is mostly performed in the multi-process task system, the number of CPU processes can be determined. If the number of CPU processes is greater than the preset number, the CPU is occupied. At this time, the pre-transmission is performed according to the present invention. If the number of CPU processes is less than or equal to the preset number, the CPU is not occupied, and can be sent according to the traditional BFD detection mechanism.

Referring to FIG. 2, FIG. 2 is a schematic flowchart diagram of a second embodiment of a link detecting method according to the present invention. Based on the first embodiment, the method further includes:

Step S40, the second terminal receives the second BFD packet that is sent by the first terminal based on the first BFD packet, and the number of times the second terminal sends the first BFD packet is less than the pre- When the threshold is set, the second terminal determines The link with the first terminal is normal.

If the second terminal receives the BFD packet sent by the first terminal in the time that the second terminal receives the preset number of the BFD packets, the second terminal accesses the received first terminal. The transmitted BFD packet is verified. If the verification succeeds, it is determined that the link between the second terminal and the first terminal is normal. If the verification fails, the first terminal sends a verification failure BFD packet to the first terminal, and may not send the authentication. If the first terminal negotiates the BFD packet, the BFD packet is sent, and the second terminal continues to send the BFD packet, and the second terminal performs the BFD packet received by the first terminal. verification.

Or, when the first terminal CPU is occupied, the first terminal receives the BFD packet sent by the second terminal, when the second terminal sends the preset number of the BFD packets. And verifying, determining that the link between the second terminal and the first terminal is normal.

The first terminal and the second terminal start detecting the received BFD packet only when the preset number of BFD packets are sent. When the first terminal and the second terminal CPU are not occupied, the CPU may be uploaded to the CPU when the preset number of BFD packets are received, and the CPU may verify the BFD packet received by the preset number of times. Each time a BFD packet is received, it is uploaded to the CPU, and the first terminal and the second terminal CPU start to verify when the first terminal or the second terminal sends a preset number of BFD packets.

Referring to FIG. 3, FIG. 3 is a second BFD packet that is received by the first terminal according to the first BFD packet, and the second terminal sends the first When the number of times of a BFD packet is less than a preset threshold, the second terminal determines a refinement flow of the step of normalizing the link between the BFD packet and the first terminal. This step includes:

Step S41: When receiving the second BFD packet that is sent by the first terminal based on the first BFD packet, determining whether the second BFD packet fed back by the first terminal is a keep-alive packet;

After the negotiation succeeds, the second terminal determines, according to the preset number of times of the BFD packet, the BFD packet sent by the first terminal, and determines whether the BFD packet is a keep-alive packet. For example, the packet sent by the CPU is a slow packet, and the sending period is more than one second, that is, more than one second. The packet sent by the hardware field editable gate array FPGA is a fast packet, and the sending time is seconds. the following. In this embodiment, the time for generating the BFD packet is calculated according to the time when the BFD packet is generated, or the period of the received BFD packet is calculated by the two nodes, and the BFD packet is sent. If the time is greater than or equal to the second level, the BFD packet is determined to be a BFD negotiation packet. In the specific implementation, the BFD message generated by the CPU and/or the hardware field editable gate array FPGA can be determined by the CPU or the hardware field editable gate array FPGA, for example, according to the mark. Judge. If the result of the determination is that the BFD message is a keep-alive message, the process proceeds to step S42, otherwise, the process proceeds to step S43.

Step S42: If the second BFD packet is a keep-alive packet, verify the second BFD packet, and if the verification succeeds, the second terminal determines that it is between the first terminal and the first terminal. The link is normal;

According to the result of the step S41, when the BFD message is a keep-alive message, the first terminal hardware can edit the gate array on site. When the column FPGA generates a preset number of BFD keep-alive messages, and then sends the BFD keep-alive message to the second terminal, or the first terminal hardware field editable gate array FPGA generates a BFD keep-alive message, and sends the message to the second terminal. For example, in the embodiment, when the hardware field editable gate array FPGA generates three numbers of BFD keep-alive messages, the first end sends the three BFD keep-alive messages generated by the hardware field editable gate array FPGA to the first end. Two ends. The second terminal receives the three BFD keep-alive messages sent by the first terminal, and performs the verification of the received BFD keep-alive packets. After the verification is passed, the second terminal generates a preset number of BFD keep-alive messages, and sends the BFD keep-alive packets. Give the first terminal. Certainly, before the first terminal and the second terminal do not receive the command to stop sending the BFD packet, the generated BFD packet can be sent to the other party, and the first terminal and the second terminal CPU receive the preset number of times. When the BFD packet is sent, the keepalive packet is verified. If the verification succeeds, the link between the second terminal and the first terminal is determined to be normal. If the verification fails, it is determined that the link between the second terminal and the first terminal is abnormal.

In step S43, the traditional BFD mechanism is sent.

According to the judgment result of the step S41, if the BFD packet is a BFD negotiation packet, the first terminal and/or the second terminal are sent and processed according to the traditional BFD mechanism. The priority of the BFD negotiation packet is also increased, so that the second terminal preferentially processes the BFD negotiation packet.

The core idea of the embodiment of the present invention is to start the detection when the preset number of BFD packets are received, and the method includes: at least three implementation manners: 1. When the second terminal receives the preset number of BFD packets sent by the first terminal at a time, The preset number of BFD packets is sent to the CPU. The second terminal receives the BFD packets sent by the first terminal in a preset time, and saves the BFD packets. The CPU is uploaded to the CPU when receiving the BFD packet sent by the first terminal. The CPU processes the received BFD packet only when it receives the preset number of BFD packets. At the same time, those skilled in the art may know that the first terminal and the second terminal may be interchanged, that is, the first terminal and the second terminal have the same function.

The embodiment of the invention further provides a link detecting device.

Please refer to FIG. 4. FIG. 4 is a schematic diagram of functional modules of a first embodiment of a link detecting apparatus according to the present invention.

In this embodiment, the link detecting apparatus includes: a generating module 10, a sending module 20, a receiving module 30, and a determining module 40.

The generating module 10 is configured to generate a first BFD packet after the negotiation between the first terminal and the second terminal BFD protocol is successful.

The sending module 20 is configured to periodically send the first BFD packet to the first terminal.

The receiving module 30 is configured to receive the second BFD packet that is sent by the first terminal based on the first BFD packet.

In the network data transmission, the BFD packet is set to the authentication parameter for the BFD session. Before the BFD session is established, the BFD session is in the Down state. The BFD session is set to be the BFD session. The BFD session is reported to the CPU. After the BFD session is established, the BFD session is set to update the BFD session parameters, or the BFD session is renegotiated. After the BFD session is established, the BFD session is set to the Up state and the BFD session is set to detect the BFD session. The normal BFD packet is a keep-alive packet, which is processed by the Field-Programmable Gate Array (FPGA). The time and port parameters included in the BFD packet are reported to the CPU for processing. In the traditional BFD detection mechanism, if the CPU fails to process in time due to task scheduling, it will cause a large number of packets in the CPU to accumulate, affecting the stability of the entire BFD operation and reducing the performance of the entire system. For example, the second terminal receives the pre-configured two-way. After forwarding the negotiation packet sent by the first terminal of the BFD protocol, the first terminal cannot process the negotiation packet and configure the hardware to send the BFD packet, so that the second terminal does not receive the message for a long time. In the BFD packet, the second terminal and/or the first terminal considers that the primary BFD link is faulty, and then switches to the standby BFD session link or sends a BFD fault packet.

For example, in this embodiment, when the second terminal receives the negotiated BFD packet sent by the first terminal, the second terminal verifies the negotiation BFD packet sent by the first terminal, and if the verification succeeds, the negotiation succeeds to the first terminal. The BFD packet is sent to the second terminal in the hardware field to edit the gate array FPGA to configure the BFD session. The hardware field editable gate array FPGA configures the BFD session to count the generated BFD keep-alive packets, and sends the generated BFD packets to the first terminal once after generating the BFD packets. Of course, it can also be set to 2 times and 4 times. In the specific implementation, the setting menu can also be entered, and the preset number of times is set for the user with different performances of the device. In a more implementation, when a BFD session is configured, the BFD packet can be sent according to the traditional mechanism. After the negotiation succeeds, a BFD packet is generated and sent to the first terminal. Before receiving the packet, the first terminal sends a corresponding keep-alive packet and/or a P-set packet, but does not detect the BFD packet and/or the P-set packet sent by the first terminal, that is, after the packet is sent. Before the preset number of BFD packets, the second terminal does not receive the BFD packet of the first terminal, and does not generate an alarm or enable other protection mechanisms, such as enabling the protection link. When the second terminal receives the preset number of BFD packets sent by the first terminal, the preset number of keep-alive messages are reported to the CPU of the second terminal.

When the first terminal receives the successfully negotiated packet, the first terminal CPU verifies the received negotiation success packet, and if the verification succeeds, notifies the first terminal hardware to edit the gate array FPGA to configure the BFD. Session, at this time, the first terminal starts to enter the UP state, and the hardware field can edit the gate array FPGA to configure the BFD session, generate BFD keep-alive packets, and count the generated BFD packets. After generating 3 BFD packets, Sending the generated three BFD packets to the second terminal, which may be set to 2 times or 4 times, of course, may also enter a setting menu, for different performances of the first terminal and/or the second terminal. Define settings. In a specific implementation, after the BFD session is entered, the BFD packet can be sent in the BFD packet according to the traditional mechanism. After receiving the BPDU, the BFD packet is sent to the BFD session. The second terminal receives a corresponding keep-alive message and/or a P-set message sent by the second terminal. When a preset number of BFD packets are received, the preset number of keep-alive messages are reported to the CPU of the first terminal. In a further implementation, after the first terminal sends the negotiation message, the hardware field editable gate array FPGA is notified to configure the BFD session. It is known in the art that the time taken to send BFD keep-alive packets is less than the preset time for detecting BFD packets in the BFD detection mechanism. For example, the preset time in the BFD detection mechanism is 5 seconds. If it is not received within 5 seconds, If the BFD session is faulty, the BFD session is faulty. The time taken for the number of BFD keepalive packets is less than 5 seconds. In the specific implementation, the preset time in the BFD detection mechanism can be adjusted.

The determining module 40 is configured to receive, in the second terminal, the second BFD packet that is sent by the first terminal based on the first BFD packet, and the second terminal sends the first BFD packet When the number of times is greater than or equal to the preset threshold, it is determined that the link between the second terminal and the first terminal is faulty.

When the number of times the BFD packet is sent to the first terminal is greater than or equal to a preset threshold, for example, in this embodiment, the first terminal CPU is occupied, and the received second terminal cannot be processed in time. The BFD packet is sent to the first terminal by the second terminal after the BFD packet is sent to the first terminal after the second terminal receives the BPDU. If the number of times of the BFD packet is greater than or equal to 3 times, if the second terminal does not receive the BFD packet sent by the first terminal, determine the link between the second terminal and the first terminal. malfunction. Of course, if the second terminal receives the BFD packet sent by the first terminal in the time that the second terminal sends the BFD packet of the preset threshold, but the verification fails, the foregoing may also be determined. The link between the second terminal and the first terminal fails. In a specific implementation, after the second terminal sends the preset number of times of the BFD packet, if the second terminal does not receive the BFD packet sent by the first terminal, the protection link is enabled for data transmission, and then And sending the BFD packet with the preset threshold number, if the BFD packet of the preset threshold is sent after the protection link is sent, the second terminal is determined to be the same as the feedback BFD packet of the first terminal. The link between the first terminal and the first terminal fails.

The determining module 40 is further configured to: receive, by the second terminal, a second BFD packet that is sent by the first terminal based on the first BFD packet, and the second terminal sends the first BFD packet When the number of times is less than a preset threshold, the second terminal determines that the link between the second terminal and the first terminal is normal.

And the second terminal sends the BFD sent by the first terminal to the received first terminal, if the second terminal receives the BFD packet sent by the first terminal in the time that the second terminal sends the preset number of the BFD packets. The message is verified, and if the verification is passed, it is determined that the link between the second terminal and the first terminal is normal. If the verification fails, the first terminal sends a verification failure BFD packet to the first terminal, and may not send the authentication. If the first terminal negotiates the BFD packet, the BFD packet is sent, and the second terminal continues to send the BFD packet, and the second terminal performs the BFD packet received by the first terminal. verification.

In a preferred implementation, the device further includes an alarm module (not shown), and the alarm module is configured to determine, according to the judgment result of the determining module 330, if the BFD session link transmission failure is determined, the first terminal and The second terminal generates a fault alarm message and sends a fault alarm message to the respective terminal CPU. Of course, the two terminals can also send the fault alarm message to the peer end. In the specific implementation, the fault alarm message can also be sent according to the preset frequency, or only the fault alarm message can be sent only before the fault state is changed, so as to reduce the fault alarm report. The burden on the CPU may of course not be sent. For example, the first terminal resends the negotiation message to the second terminal through the CPU. The CPU receives the fault alarm packet and searches for the BFD information table. The preset BFD information table stores a BFD information index table, which mainly involves communication problems between the BFD packet and the BFD link. When the BFD link is faulty, the corresponding fault alarm packet is found and the corresponding problem is processed. In a further implementation, the preset BFD information table may be used to determine whether there is a preset stop flag in the BFD packet, and if it is determined that there is a stop flag in the BFD packet, the fault alarm report is If the stop flag in the preset BFD information table is found, the BFD packet is stopped.

Please refer to FIG. 5. FIG. 5 is a schematic diagram of the refinement function module of the judging module in FIG.

Based on the first embodiment of the link detecting apparatus of the present invention, the determining module 40 includes: a determining unit 41 and a verifying unit 42.

The determining unit 41 is configured to determine whether the second BFD packet fed back by the first terminal is a keep-alive packet when receiving the second BFD packet that is fed back by the first terminal according to the first BFD packet.

After the negotiation succeeds, when receiving the second BFD packet that is sent by the first terminal based on the first BFD packet, the device determines the BFD packet to be a keep-alive packet. . In the specific implementation, the number of CPU processes can also be judged, because the task behaviors involving the CPU are mostly performed in the multi-process task system, and the number of CPU processes can be determined. If the number of CPUs is large, for example, the number of CPU processes is greater than the preset. The quantity indicates that the CPU is occupied. At this time, according to the embodiment of the present invention, the preset number of BFD messages are sent at a preset time; if the number of CPU processes is less than or equal to the preset number, it indicates that the CPU is not occupied, then press The traditional BFD detection mechanism is sent.

The verification unit 42 is configured to verify the second BFD message when the second BFD message is a keep-alive message, and if the verification is passed, the determining module 40 determines that the The link between the second terminal and the first terminal is normal.

According to the judgment result of the determining unit 41, when the BFD message is a keep-alive message, the first terminal hardware field editable gate array FPGA generates a preset number of BFD keep-alive messages, and then sends the BFD keep-alive message to the second terminal. For example, in the embodiment, when the hardware field editable gate array FPGA generates three numbers of BFD keep-alive messages, the first end sends the three BFD keep-alive messages generated by the hardware field editable gate array FPGA to the first end. Second end. The second terminal receives the three BFD keep-alive messages sent by the first terminal, and performs the verification of the received BFD keep-alive packets. After the verification is passed, the second terminal generates a preset number of BFD keep-alive messages, and sends the BFD keep-alive packets. Give the first terminal to complete the verification of the UP state. If the judgment result of the determining unit 321 is that the BFD packet is a BFD negotiation packet, the first terminal and/or the second terminal send and process according to the traditional BFD mechanism.

Please refer to FIG. 6. FIG. 6 is a schematic diagram of the refinement function module of the judging unit in FIG. Based on the above embodiment, the determination unit 41 in the link detecting apparatus includes a calculation subunit 411, a judgment subunit 412, and a decision subunit 413.

The calculation sub-unit 411 is configured to calculate a time interval of each BFD message fed back by the first terminal, based on a period of the second BFD message fed back by the first terminal.

Generally, the packets sent by the CPU are slow packets, and the sending period is more than one second, that is, more than one second. The packets sent by the hardware field editable gate array FPGA are fast packets, and the sending time is less than the second. In this embodiment, the time for generating the BFD packet is calculated according to the BFD packet generation time, or the period of the received BFD packet is calculated by the two terminals, and the calculation time of each BFD packet is calculated, and the calculation subunit may not be included in the implementation. For example, in the CPU and / or hardware field editable gate array FPGA generated BFD message as a mark, judged according to the mark.

The determining sub-unit 412 is configured to determine whether the feedback time interval of each BFD message fed back by the first terminal is smaller than when the calculation result of the calculation of the sub-unit 411 is that the feedback time of each BFD packet is less than the preset time. Preset time.

The determining sub-unit 413 is configured to determine that the BFD message is a keep-alive message when the determining sub-unit 412 determines that the feedback time interval of each of the BFD messages fed back by the first terminal is less than a preset time.

The above are only the preferred embodiments of the present invention, and are not intended to limit the scope of the invention, and the equivalent structure or equivalent process transformations made by the description of the present invention and the drawings are directly or indirectly applied to other related technical fields. The same is included in the scope of patent protection of the present invention.

Industrial applicability

As described above, the link detection method and apparatus provided by the embodiments of the present invention have the following beneficial effects: after the negotiation succeeds, the second terminal continues to send the preset number of BFD packets without waiting for the first After the BFD packet sent by the terminal sends the preset threshold BFD packet, the second terminal determines that the link between the terminal and the first terminal is faulty. It is possible to avoid unnecessary switching caused by the first terminal and the second terminal being unsynchronized, and to improve the negotiation of the INIT due to the failure of the first terminal CPU to process the BFD packet that needs to be sent in time in the large-capacity scenario. The technical problem that the BFD link in the UP state returns to the Down state due to timeout, thereby improving the reliability of the BFD detection mechanism.

Claims

A link detection method, the method comprising the following steps:

After the first terminal and the second terminal BFD protocol are successfully negotiated, the second terminal generates a first BFD packet, and periodically sends the first BFD packet to the first terminal.

Receiving, by the second terminal, the second BFD packet that is sent by the first terminal based on the first BFD packet, and the number of times that the second terminal sends the first BFD packet is greater than or equal to a pre- When the threshold is set, the second terminal determines that the link between the first terminal and the first terminal has failed.
The method of claim 1, wherein the step of determining that the link between the second terminal and the first terminal has failed comprises:

The second terminal generates a fault alarm message and stops sending BFD packets.
The method of claim 1 wherein the method further comprises:

When the second terminal receives the second BFD packet that is sent by the first terminal based on the first BFD packet, and the number of times that the second terminal sends the first BFD packet is less than a preset threshold The second terminal determines that the link between the first terminal and the first terminal is normal.
The method of claim 3, wherein the second terminal receives a second BFD message that is sent by the first terminal based on the first BFD packet, and the second terminal sends a When the number of times that the first BFD packet is less than the preset threshold, the step of the second terminal determining that the link between the first terminal and the first terminal is normal includes:

And determining, by the first terminal, whether the second BFD packet fed back by the first terminal is a keep-alive packet, according to the second BFD packet that is sent by the first terminal according to the first BFD packet;

If the second BFD packet is a keepalive packet, the second BFD packet is verified, and if the verification succeeds, the second terminal determines that the link between the second terminal and the first terminal is normal. .
The method of claim 4, wherein the step of determining whether the second BFD message fed back by the first terminal is a keep-alive message comprises:

The second terminal calculates a feedback time interval of each BFD packet fed back by the first terminal, based on a period of the second BFD packet that is fed back by the first terminal;

The second terminal determines whether the feedback time interval of each BFD packet fed back by the first terminal is less than a preset time;

If the result of the determination is that the feedback time interval of each BFD packet fed back by the first terminal is less than the preset time, the second BFD packet is determined to be a keep-alive message.
A link detecting device, the device comprising:

The generating module is configured to generate a first BFD packet after the negotiation between the first terminal and the second terminal BFD protocol is successful;

a sending module, configured to periodically send the first BFD packet to the first terminal;

a receiving module, configured to receive a second BFD packet that is sent by the first terminal according to the first BFD packet;

a determining module, configured to: in the second terminal, not receiving the second BFD packet that is sent by the first terminal based on the first BFD packet, and the second terminal sending the first BFD packet When the number of times is greater than or equal to the preset threshold, it is determined that the link between the second terminal and the first terminal is faulty.
The device of claim 6 wherein said device further comprises:

The alarm module is configured to generate a fault alarm message when the link is faulty.
The device of claim 6, wherein the determining module is further configured to receive, by the second terminal, a second BFD packet that is fed back by the first terminal based on the first BFD packet, and the When the number of times that the second terminal sends the first BFD packet is less than or equal to a preset threshold, determining that the link between the second terminal and the first terminal is normal.
The apparatus of claim 8, wherein the determining module comprises: a determining unit and a verifying unit,

The determining unit is configured to determine, according to the second BFD packet that the first terminal feeds back based on the first BFD packet, whether the second BFD packet fed back by the first terminal is a keep-alive packet. ;

The verification unit is configured to verify the second BFD packet when the judgment result of the determining unit is that the second BFD packet is a keep-alive packet, and if the verification succeeds, determine the second The link between the terminal and the first terminal is normal.
The apparatus according to claim 9, wherein said judgment unit comprises a calculation subunit, a judgment subunit, and a decision subunit,

The calculating subunit is configured to calculate a time interval of each BFD packet fed back by the first terminal, based on a period of the second BFD packet that is fed back by the first terminal;

The determining subunit is configured to determine whether a feedback time interval of each BFD packet fed back by the first terminal is less than a preset time;

The determining subunit is configured to determine that the BFD packet is a keep-alive report when the judgment subunit determines that the feedback time interval of each of the BFD packets fed back by the first terminal is less than a preset time. Text.