WO2023197644A1

WO2023197644A1 - Cross-segmented network fault detection method, and communication system and related apparatus

Info

Publication number: WO2023197644A1
Application number: PCT/CN2022/138069
Authority: WO
Inventors: 李大成; 生绪博; 曾海飞; 成名
Original assignee: 华为技术有限公司
Priority date: 2022-04-15
Filing date: 2022-12-09
Publication date: 2023-10-19

Abstract

The embodiments of the present application belong to the technical field of communications. Disclosed are a cross-segmented network fault detection method, and a communication system and a related apparatus. The method comprises: a first forwarding node acquiring the state of a BFD group, wherein the BFD group comprises a BFD session of each path in a plurality of paths corresponding to the first forwarding node in a second segmented network, and the BFD session is used for detecting a fault in a corresponding path; and the first forwarding node notifying, on the basis of the state of the BFD group, a second forwarding node of fault conditions of the plurality of paths. Compared with a single-point fault detection mode, the embodiments of the present application provide a cross-segmented network multi-fault-point detection mode since the second forwarding node is notified of the fault conditions of the plurality of paths on the basis of the state of the BFD group in the embodiments of the present application, thereby improving the flexibility of fault detection.

Description

Fault detection method, communication system and related devices across segmented networks

This application claims priority to the Chinese patent application with application number 202210400005.8 and the invention title "A method for fast switching of segmented cascading fault scenarios" submitted on April 15, 2022, as well as the Chinese patent application submitted on June 10, 2022 The priority of the Chinese patent application with application number 202210657604.8 and the invention title "Fault detection method, communication system and related devices across segmented networks", the entire content of which is incorporated into this application by reference.

Technical field

Embodiments of the present application relate to the field of communication technology, and in particular to a fault detection method across segmented networks, a communication system and related devices.

Background technique

In order to improve network security and stability, communication networks can be divided into multiple segmented networks. Different segmented networks are used to carry different services. For example, two adjacent segmented networks can be used to carry the segment routing policy (Segment Routing IPv6 Policy, SRv6 policy) service based on the sixth generation network protocol and the shortest path (Segment Routing IPv6 Policy, SRv6 policy) based on the sixth generation network protocol respectively. Segment Routing IPv6 Best Effort, SRv6 BE) business, or used to carry virtual leased line (Virtual Leased Line, VLL) business and virtual private line service (Virtual Private Lan Service, VPLS) business respectively. Among them, multiple edge forwarding nodes are deployed between adjacent segmented networks. Any edge forwarding node is used to divert the packet flow in the upper-level segmented network to the next-level segmented network, thereby realizing the packet flow. Transmission across segmented networks. In the scenario of transmitting message flows across segmented networks, how to detect faults across segmented networks is a current research hotspot.

In the related art, for any edge forwarding node between the adjacent upper-level segment network and the next-level segment network, the edge forwarding node may correspond to multiple paths in the next-level segment network. This is A path is used to forward the packet flow received from the target incoming interface within the next-level segmented network. Each of these multiple paths is configured with a bidirectional forwarding detection (BFD) session. When the status of the BFD session on any path is down, the status of the target incoming interface is triggered to be updated to the down status. When the forwarding node in the upper-level segmented network detects that the status of the target incoming interface is down, it can determine that there is a fault in the lower-level segmented network. However, this method of fault detection is less flexible.

Contents of the invention

Embodiments of the present application provide a fault detection method, communication system and related devices across segmented networks, which can improve the flexibility of fault sensing across segmented networks. The technical solutions are as follows:

In a first aspect, a fault detection method across segmented networks is provided. The method is applied to a communication system. The communication system includes a first forwarding node and a second forwarding node. The first forwarding node is a first segmented network and a second forwarding node. The edge node between the two segmented networks, the second forwarding node is located within the first segmented network.

In this method, the first forwarding node obtains the status of the BFD group. The BFD group includes the BFD session of each of the multiple paths corresponding to the first forwarding node in the second segment network. The BFD session is used to detect the corresponding Path failure: the first forwarding node notifies the second forwarding node of multiple path failures based on the status of the BFD group.

In this embodiment of the present application, the first forwarding node notifies the second forwarding node of the fault conditions of multiple paths based on the status of the BFD group. On the one hand, since the BFD group includes BFD sessions of multiple paths, multi-point fault detection within the second segmented network can be implemented, which improves the flexibility of fault detection. On the other hand, since BFD sessions can be deployed on any form of link such as physical links, pseudo-wires (pseudo-wires), tunnels, etc., the fault detection method provided by the embodiments of this application can realize the detection of physical outbound interfaces and logical outbound interfaces. Fault detection on the path corresponding to the interface improves the scope of fault detection.

Based on the method provided in the first aspect, in a possible implementation manner, the implementation process for the first forwarding node to obtain the status of the BFD group may be: when each BFD session in the BFD group is in a closed state, The status of the BFD group obtained by a forwarding node is the closed state; when the status of at least one BFD session in the BFD group is the open state, the status of the BFD group obtained by the first forwarding node is the open state.

Based on the relationship between the status of the above BFD group and the status of each BFD session in the BFD group, the status of the BFD group provided by the embodiment of the present application can indicate whether there is a BFD session in the BFD group whose status is closed, or in other words , can indicate whether all BFD sessions in the BFD group are closed. This is so that the fault conditions of multiple paths can be subsequently notified to the second forwarding node based on the status of the BFD group.

Based on the method provided in the first aspect, in one possible implementation, the implementation process of the first forwarding node notifying the second forwarding node of the fault conditions of multiple paths based on the status of the BFD group may be: the first forwarding node based on The status of the BFD group and the process of processing the upper-level BFD session. The upper-level BFD session is used to detect the failure of the path between the first forwarding node and the second forwarding node.

Through the above implementation method, the first forwarding node can link the upper-level BFD session to notify the fault conditions of multiple paths based on the status of the BFD group. On the one hand, it will not cause too much change to the existing network and improve the embodiment of the present application. compatibility. On the other hand, linking the upper-level BFD session to notify the fault conditions of multiple paths can enable the second forwarding node to quickly detect faults, which is beneficial to the second forwarding node to quickly change paths.

Based on the method provided in the first aspect, in a possible implementation manner, the first forwarding node can implement the process of processing the upper-level BFD session based on the status of the BFD group as follows: If the status of the BFD group is closed status, the first forwarding node does not send the first BFD message to the second forwarding node. Correspondingly, if the status of the BFD group is open, the first forwarding node sends the first BFD message to the second forwarding node.

Both parties in a BFD session periodically send BFD packets so that the other end can determine whether a fault exists based on the reception of BFD packets. Therefore, when the first forwarding node periodically sends BFD packets to the second forwarding node, if it detects that the status of the BFD group is closed, it will no longer send BFD packets to the second forwarding node, so that the second forwarding node The node will detect that there is a fault in the upper-level BFD session, that is, it will detect that there is a fault on the first forwarding node, thereby passing the fault conditions of multiple paths to the first forwarding node through the upper-level BFD session, achieving cross-bundling Fault detection on segmented networks.

Based on the method provided in the first aspect, in a possible implementation manner, the first forwarding node can implement the process of processing the upper-level BFD session based on the status of the BFD group as follows: If the status of the BFD group is closed status, the first forwarding node sets the status of the upper-level BFD session to the closed state, and sends a status notification message to the second forwarding node. The status notification message indicates that the status of the upper-level BFD session is closed. Correspondingly, if the status of the BFD group is in the open state, the first forwarding node does not perform the operation of setting the upper-level BFD session status to the closed state.

In a BFD session, the first forwarding node has the ability to directly set the BFD session status to the closed state and advertise the BFD session status. Therefore, if the first forwarding node detects that the status of the BFD group is closed, it directly sets the status of the upper-level BFD session to the closed state, and sends a status notification message to the second forwarding node. In this way, the second forwarding node will It is detected that there is a fault in the upper-level BFD session, that is, it is detected that there is a fault on the first forwarding node, so that the fault conditions of multiple paths are passed to the first forwarding node through the upper-level BFD session, achieving cross-segment network fault detection.

Based on the method provided in the first aspect, in a possible implementation manner, the first forwarding node based on the status of the BFD group, the implementation process of processing the upper-level BFD session may be: after receiving the message from the second forwarding node When receiving the second BFD packet, if the status of the BFD group is closed, the first forwarding node discards the second BFD packet and does not update the BFD packets received in the current BFD detection cycle based on the second BFD packet. Quantity operations. Correspondingly, if the status of the BFD group is open, the first forwarding node updates the number of BFD packets received in the current BFD detection cycle based on the second BFD packet.

In a BFD session in asynchronous mode, if the first forwarding node receives a BFD packet sent by the second forwarding node, it does not update the number of BFD packets received in the current BFD detection cycle (that is, discards the received BFD packets). message), then when the current detection cycle is reached, the number of BFD packets counted by the first forwarding node will not reach the required number. At this time, the first forwarding node determines that the status of the upper-level BFD session is closed. and sends a status notification message to the second forwarding node. In this way, the second forwarding node will detect that there is a fault in the upper-level BFD session, that is, it will detect that there is a fault in the first forwarding node, thereby passing the fault conditions of multiple paths to the first forwarding node through the upper-level BFD session. , to achieve fault detection across segmented networks.

Based on the method provided in the first aspect, in a possible implementation manner, the first forwarding node based on the status of the BFD group, the implementation process of processing the upper-level BFD session may be: after receiving the message from the second forwarding node When receiving the third BFD packet, if the status of the BFD group is closed, the first forwarding node discards the third BFD packet and does not perform the operation of returning the third BFD packet to the second forwarding node. Correspondingly, if the status of the BFD group is open, the first forwarding node returns the third BFD packet to the second forwarding node.

In a BFD session or SBFD session in query mode, if the first forwarding node does not return the BFD message to the second forwarding node when receiving the BFD message sent by the second forwarding node, the second forwarding node will The BFD packet returned by the first forwarding node cannot be received. In this way, the second forwarding node will detect that there is a fault in the upper-level BFD session, that is, it will detect that there is a fault in the first forwarding node, thereby passing the fault conditions of multiple paths to the first forwarding node through the upper-level BFD session. , to achieve fault detection across segmented networks.

Based on the method provided in the first aspect, in a possible implementation manner, the upper-level BFD session is a BFD session in asynchronous mode, a BFD session in query mode or a seamless bidirectional forwarding detection SBFD session.

The upper-level BFD sessions linked in this embodiment of the present application include BFD sessions specified in various standard protocols, which improves the flexibility of fault sensing across segmented networks.

Based on the method provided in the first aspect, in a possible implementation manner, in this method, the first forwarding node can also obtain the BFD group; the first forwarding node determines the corresponding relationship between the BFD group and the upper-level BFD session. .

In order to be able to link the status of the BFD group with the upper-level BFD session, it is necessary to bind the upper-level BFD session to the BFD group in advance to establish the corresponding relationship between the BFD group and the upper-level BFD session, and based on The status of the BFD group handles the process of the upper-level BFD session.

Based on the method provided in the first aspect, in one possible implementation, the implementation process of the first forwarding node notifying the second forwarding node of the fault conditions of multiple paths based on the status of the BFD group may be: the first forwarding node The second forwarding node sends a fault notification message, and the fault notification message is used to notify the second forwarding node of fault conditions of multiple paths.

In addition to reporting faults through linkage with the upper-level BFD session, faults can also be reported separately through fault notification messages. Improved flexibility in fault awareness across segmented networks.

Based on the method provided in the first aspect, in a possible implementation manner, the fault notification message carries the status of the BFD group.

When the fault notification message carries the status of the BFD group, the second forwarding node can quickly determine fault conditions of multiple paths based on the fault notification message.

Based on the method provided in the first aspect, in one possible implementation, before the first forwarding node obtains the status of the BFD group, the first forwarding node can also periodically obtain the BFD session status of each path in the multiple paths; The first forwarding node periodically updates and stores the status of the BFD group based on the BFD session status of each of the multiple paths. In this scenario, the implementation process for the first forwarding node to obtain the status of the BFD group may be: the first forwarding node obtains the stored status of the BFD group.

The first forwarding node can periodically determine and store the status of the BFD group in advance, so that the second forwarding node can quickly detect faults and facilitate rapid path change by the second forwarding node.

Based on the method provided in the first aspect, in a possible implementation manner, the implementation process for the first forwarding node to obtain the status of the BFD group may be: the first forwarding node obtains the BFD session status of each path among the multiple paths; The first forwarding node determines the status of the BFD group based on the BFD session status of each of the multiple paths.

The first forwarding node may also temporarily determine the status of the BFD group. In this scenario, the first forwarding node does not need to periodically update and store the status of the BFD group, which saves the storage pressure and data processing pressure of the first forwarding node.

Based on the method provided in the first aspect, in a possible implementation manner, the aforementioned multiple paths are used to forward the message flow from the second forwarding node.

Based on the method provided by this application, the second forwarding node can sense the failure of the path that the message flow sent by the local end may use in the second segmented network, so as to facilitate path change when a failure is detected and avoid data transmission. Packet loss.

Based on the method provided in the first aspect, in a possible implementation manner, the first segmented network and the second segmented network are respectively used to carry at least one of the following services: SRv6 Policy service, SRv6 BE service, VLL Services, VPLS services; the services carried by the first segment network are different from the services carried by the second segment network.

The cross-segmented network fault detection method provided by the embodiments of the present application can be applied in various cascaded segmented network scenarios, which improves the flexibility of the embodiments of the present application.

Based on the method provided in the first aspect, in a possible implementation manner, the implementation process for the first forwarding node to obtain the status of the BFD group may be: obtaining the status of the BFD group on the forwarding plane of the first forwarding node.

When the status of the BFD group is obtained on the forwarding plane, the second forwarding node can quickly perceive the fault condition of the path that the packet flow sent by the local end may use in the second segmented network, thereby facilitating the detection of the fault. Change the path when necessary to avoid data packet loss.

Based on the method provided in the first aspect, in a possible implementation manner, the first forwarding node notifies the second forwarding node of the fault conditions of multiple paths based on the status of the BFD group. The implementation method may be: at the first forwarding node The forwarding plane notifies the second forwarding node of the fault conditions of multiple paths based on the status of the BFD group.

When the fault conditions of multiple paths are announced on the forwarding plane, the second forwarding node can quickly sense the fault conditions of the paths that the packet flow sent by the local end may use in the second segmented network, thereby facilitating the detection. In case of failure, the path is changed to avoid data packet loss.

In a second aspect, a communication system is provided. The system includes a first forwarding node and a second forwarding node. The first forwarding node is used to perform any method as provided in the first aspect.

In a third aspect, a network device is provided, the network device including a memory and a processor;

Memory is used to store program instructions;

The processor is configured to call a program stored in the memory, so that the network device executes any method provided in the first aspect.

In a fourth aspect, a network device is provided. The network device is a first forwarding node in a communication system. The communication system further includes a second forwarding node. The first forwarding node is a first segmented network and a second forwarding node. An edge node between segmented networks, the second forwarding node is located in the first segmented network; the first forwarding node includes a transceiver module and a processing module:

The transceiver module is configured to perform transceiver-related operations in any method provided in the first aspect;

The processing module is configured to perform operations other than the transceiver-related operations in any method provided in the first aspect.

In a fifth aspect, a computer-readable storage medium is provided. Instructions are stored in the computer-readable storage medium. When the instructions are run on a processor, any method provided in the first aspect is implemented.

In a sixth aspect, a computer program product is provided. The computer program product includes instructions. When the instructions are run on a processor, any one of the methods provided in the first aspect is implemented.

The technical effects obtained by the above-mentioned second to sixth aspects are similar to those obtained by the corresponding technical means in the first aspect, and will not be described again here.

Description of the drawings

Figure 1 is a schematic architectural diagram of a communication system provided by an embodiment of the present application;

Figure 2 is a flow chart of a cross-segmented network fault detection method provided by an embodiment of the present application;

Figure 3 is a schematic architectural diagram of another communication system provided by an embodiment of the present application;

Figure 4 is a schematic diagram of a group configuration interface provided by an embodiment of the present application;

Figure 5 is a schematic diagram of another group configuration interface provided by an embodiment of the present application;

Figure 6 is a schematic structural diagram of a network device provided by an embodiment of the present application;

Figure 7 is a schematic structural diagram of a device provided by an embodiment of the present application;

Figure 8 is a schematic structural diagram of another device provided by an embodiment of the present application;

Figure 9 is a schematic architectural diagram of a communication system provided by an embodiment of the present application.

Detailed ways

In order to make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the embodiments of the present application will be described in further detail below with reference to the accompanying drawings.

Before explaining the embodiments of the present application in detail, the application scenarios of the embodiments of the present application are first introduced.

Currently, in Internet Protocol (IP) network deployment, most end-to-end networks are formed by cascading segmented networks. Different segmented networks are used to carry different services, so that the end-to-end packet flow forwarding process is implemented by different services, thereby improving the flexibility of the IP network. This way of forwarding packet flows is also called forwarding packet flows across segmented networks.

For the convenience of subsequent explanation, the services carried on the segmented network are called segmented services. Segmentation services specifically refer to how segmented networks forward packet flows. For example, segmented services may include SRv6 policy services, SRv6 BE services, VLL services, and VPLS services. For details of the services in the foregoing examples, please refer to the relevant standard protocols and will not be described in detail here. In addition, the segmented services in the embodiment of the present application are not limited to the above four types. Any service used to implement packet flow forwarding is within the scope of the segmented service in the embodiment of the present application.

In the scenario of forwarding packet flows across segmented networks, for the adjacent upper-level segmented network and lower-level segmented network, when a fault occurs in the lower-level segmented network, the upper-level segmented network needs to quickly This fault is sensed so that the upper-level segmented network can quickly switch the forwarding path of the packet flow, thereby avoiding packet loss in the packet flow between end-to-end.

In some scenarios, the upper-level segmented network can sense faults in the lower-level segmented network through protocol convergence (such as Hello messages). However, due to the slow convergence speed, the detection time of this fault detection method is usually at the second (s) level. The transmission rate level of the message flow is gigabit per second (GB/s). In this way, within the S-level detection duration, a large number of packet loss events will occur, resulting in a large number of packet loss in end-to-end traffic.

Based on this, embodiments of the present application provide a fault detection method across segmented networks to avoid relying on protocol hard convergence to detect faults, which may lead to a large number of packet losses in message flows.

The following explains the network architecture involved in the embodiments of this application.

Figure 1 is a schematic architectural diagram of a communication system provided by an embodiment of the present application. As shown in Figure 1, the communication system includes a first terminal 10 and a second terminal 20, and a first segment network 30 and a second segment network 40 are deployed between the first terminal 10 and the second terminal 20. The first segmented network 30 is a segmented network close to the first terminal 10 , and the second segmented network 40 is a segmented network close to the second terminal 20 .

It should be noted that multiple segmented networks may be deployed between the first terminal 10 and the second terminal 20. Figure 1 takes two segmented networks as an example for illustration, and does not constitute a communication system provided by the embodiment of the present application. restrictions.

For the convenience of subsequent explanation, the services carried by the first segmented network 30 are called first segmented services, and the services carried by the second segmented network 40 are called second segmented services. That is, the services carried by the first segmented network 30 are called The forwarding node forwards the message flow based on the first segmented service, and the forwarding node in the second segmented network 40 forwards the message flow based on the second segmented service.

Among them, the first segmented network and the second segmented network are respectively used to carry at least one of the following services: SRv6 Policy service, SRv6 BE service, VLL service, and VPLS service. Moreover, the services carried by the first segmented network are different from the services carried by the second segmented network. It should be noted that the first segment business and the second segment business are not limited to the above four types. Any business used to implement packet flow forwarding is within the scope of the first segment business and the second segment business. .

In some embodiments, as shown in Figure 1, the communication system is deployed with a first forwarding node R1, a second forwarding node R2, a third forwarding node R3, a fourth forwarding node R4, a fifth forwarding node R5, a sixth forwarding node Node R6, seventh forwarding node R7.

The first forwarding node R1 and the fourth forwarding node R4 are edge forwarding nodes between the first segment network 20 and the second segment network 30 . The second forwarding node R2 and the third forwarding node R3 are located within the first segmented network 20 . The fifth forwarding node R5 and the sixth forwarding node R6 are located within the second segment network 30 . The seventh forwarding node R7 is located between the second segment network 40 and the second terminal 20 .

As shown in FIG. 1 , the first terminal 10 is connected to the second forwarding node R2 to forward the message stream sent by the first terminal 10 to the second terminal 20 to the first segmented network 30 through the second forwarding node R2.

The second forwarding node R2 is also connected to the first forwarding node R1 and the third forwarding node R3 respectively, and the third forwarding node R3 is also connected to the fourth forwarding node R4. The path between the second forwarding node R2 and the first forwarding node R1 may be called a primary path, and the path composed of the second forwarding node R2, the third forwarding node R3, and the fourth forwarding node R4 may be called a backup path. In this way, when the second forwarding node R2 receives the message flow from the first terminal 10, it can send it to the edge forwarding node R1 or R4 through the main path or the backup path in Figure 1, respectively, so that the edge forwarding node R1 or R4 The packet flow is forwarded to the second segmented network 40 .

The first forwarding node R1 is also connected to the fourth forwarding node R4, the fifth forwarding node R5 and the sixth forwarding node R6 respectively. The fourth forwarding node R4 is also connected to the fifth forwarding node R5 and the sixth forwarding node R6 respectively, and the fifth forwarding node R5 is also connected to the sixth forwarding node R6. The fifth forwarding node R5 and the sixth forwarding node R6 are also connected to the seventh forwarding node R7 respectively. The seventh forwarding node R7 is also connected to the second terminal 20 .

In this way, when the first forwarding node R1 receives the message flow from the second forwarding node R2, the first forwarding node R1 can forward the message through any of the three paths corresponding to the segmented service 2 in Figure 1. flow, so that the message flow reaches the second terminal 20.

For the convenience of subsequent explanation, for the following three paths, the path between the first forwarding node R1 and the sixth forwarding node R6, the path between the first forwarding node R1 and the fifth forwarding node R5, the path between the first forwarding node R1 and the fourth forwarding node R5. The paths between the forwarding nodes R4 are called the three paths corresponding to the first forwarding node R1. In this embodiment of the present application, the three paths corresponding to the first forwarding node R1 may include: paths located in the second segment network 40 and used by the first forwarding node R1 to forward the message flow from the second forwarding node R2. .

Similarly, when the fourth forwarding node R4 receives the message flow from the second forwarding node R2, the fourth forwarding node R4 can also forward the message flow through any of the corresponding three paths, so that the message The stream reaches the second terminal 20. For the three paths corresponding to the fourth forwarding node R4, please refer to the relevant description of the three paths corresponding to the first forwarding node R1, which will not be described again here.

In the above end-to-end packet flow forwarding scenario, when the path corresponding to the first forwarding node R1 fails, the second forwarding node R2 in the first segmented network 30 needs to sense the failure in order to reselect the path. To forward the packet flow from the first terminal 10 through the backup path. Among them, the second forwarding node R2 in the first segment network 30 senses the fault condition of the path corresponding to the first forwarding node R1 in the second segment network 40. This process can be called cross-segment network fault detection.

To shorten fault detection time, fault detection across segmented networks can be implemented based on BFD sessions. For ease of understanding, the BFD session is explained here.

BFD provides a universal, standard, simple and fast fault detection protocol that is independent of media and protocols. The purpose of this protocol is to detect the forwarding connectivity status of the intermediate link where BFD is deployed. The principle of BFD is to establish a BFD session channel based on the intermediate link between two systems or devices, and continuously and periodically send BFD packets (also called BFD detection packets) to each other on the intermediate link. Both parties have If one party does not receive the specified number of BFD messages from the opposite end within the specified time, it will consider that a certain part of the intermediate link has failed, close the BFD session channel, and delete the route and reduce/increase the path priority. and other operations to ensure traffic re-routing, thereby achieving rapid traffic switching.

The current technology that implements fault detection across segmented networks based on BFD sessions is mainly the "BFD trigger if-down" technology.

The following uses the first forwarding node R1 in Figure 1 as an example to explain the "BFD trigger if-down" technology.

In Figure 1, the first forwarding node R1 deploys a BFD session on each of the three corresponding paths in the second segment network 40. Each BFD session is associated with the target incoming interface on the first forwarding node R1. The target incoming interface is the incoming interface on the first forwarding node R1 used to receive the packet flow from the second forwarding node R2.

When the BFD session on any of these three paths fails, since the BFD session on this path has been associated with the target incoming interface, the target incoming interface will be triggered to shut down, which will trigger the second forwarding node R2 to reroute.

The "BFD trigger if-down" technology has the following three problems:

(1) When any one of the three corresponding paths in the second segment network 40 fails, the first forwarding node R1 will trigger the second forwarding node R2 to sense the failure. Therefore, this fault detection method can only detect single-point faults. Single-point faults can be understood as only detecting faults on one of the paths. If a single point failure triggers the second forwarding node R2 to reroute, it will easily lead to a waste of network resources.

Based on this, the fault detection method provided by the embodiments of the present application can realize multi-point fault detection, and the detailed implementation method will be explained in subsequent embodiments.

(2) Each BFD session is associated with the target ingress interface on the first forwarding node R1, which refers to the association on the control plane. That is, when specifically detecting a fault, the control plane of the first forwarding node R1 first obtains the fault status of the BFD session of each path, and then the control plane of the first forwarding node R1 obtains the fault status of the BFD session of each path based on the fault status. Determine whether to close the target inbound interface. If the control plane of the first forwarding node R1 determines to close the target inbound interface, the control plane of the first forwarding node R1 issues a close command to the forwarding plane of the first forwarding node R1, so that the first forwarding node R1 The forwarding plane of node R1 updates the status of the target incoming interface to the down state.

This linkage on the control surface cannot achieve rapid switching of traffic. Based on this, the fault detection method provided by the embodiment of the present application can realize linkage on the forwarding plane, thereby increasing the traffic switching rate in the event of a fault. Detailed implementation will be explained in subsequent embodiments.

(3) Since the current "BFD trigger if-down" technology can only achieve single-point fault detection, in order to cover more fault situations, BFD needs to be deployed based on each route of the first forwarding node R1 in the second segment network 40 session.

For example, a route located in the second segment network 40 is deployed for the first forwarding node R1. The route includes three outbound interfaces, and the three outbound interfaces are the outbound interfaces between R1 and R4, R5 and R6 respectively. Load sharing is formed between the three outgoing interfaces. Then deploy a BFD session to detect the route. If there is a fault in the route, the status of the BFD session is updated to the closed state to achieve "BFD trigger if-down".

However, the way of deploying BFD sessions based on routing is not flexible enough. Based on this, the fault detection method provided by the embodiment of the present application can realize multi-point fault detection without deploying BFD sessions based on routing. Detailed implementation will be explained in subsequent embodiments.

The cross-segmented network fault detection method provided by the embodiment of the present application is explained in detail below.

Figure 2 is a flow chart of a cross-segmented network fault detection method provided by an embodiment of the present application. As shown in Figure 2, the method includes the following steps 201 and 202.

Step 201: The first forwarding node obtains the status of the bidirectional forwarding detection BFD group. The BFD group includes the BFD session of each of the multiple paths corresponding to the first forwarding node in the second segmented network. The BFD session is used for detection. Failure of the corresponding path.

The multiple paths may be all or part of the paths used to forward the message flow from the second forwarding node. Optionally, the multiple paths may be all or part of the paths in the second segmented network corresponding to the first forwarding node.

It should be noted that since each path corresponds to an outbound interface on the first forwarding node, the multiple paths in this embodiment of the present application can be respectively identified by multiple outbound interfaces on the first forwarding node.

For example, there are a total of 10 outbound interfaces on the first forwarding node for forwarding packet flows to the second segmented network. Five of these 10 outbound interfaces are used to forward packet flows from the second forwarding node. Each outbound interface corresponds to a path for forwarding packet flows within the second segmented network. In this scenario, the multiple paths in step 201 may be the five paths corresponding to the five outbound interfaces, or they may be at least two of the five paths. Alternatively, the multiple paths in step 201 may be the 10 paths corresponding to the 10 outbound interfaces, or may be most of the 10 paths.

For example, for the first forwarding node R1 shown in Figure 1, the multiple paths in step 201 may be the three paths marked with segment service 2 in Figure 1. It can also be two of these three paths.

Since the BFD group includes BFD sessions for each of the multiple paths, and the multiple paths can have the above situations, the BFD sessions in the BFD group can be flexibly configured based on actual needs, which improves the capabilities provided by the embodiments of the present application. method flexibility.

For example, as shown in Figure 3, the BFD session on the path from R1 to R6 is called BFD session 1, the BFD session on the path from R1 to R5 is called BFD session 2, and the BFD session on the path from R1 to R4 is called BFD session 2. BFD session 3. At this time, the BFD group may include BFD session 1, BFD session 2, and BFD session 3. It may also include any two of BFD session 1, BFD session 2, and BFD session 3.

In addition, in this embodiment of the present application, the members of the BFD group can be configured by developers. In some embodiments, the administrator can configure the group members in the BFD group by: the first forwarding node responds to the group member adding operation and uses the BFD session of each path in the multiple paths as the BFD session in the BFD group. BFD session.

Specifically, the first forwarding node displays a group configuration interface, which includes a BFD session configuration option; in response to the developer's triggering operation on the BFD session configuration option, the BFD session of each path in the multiple paths is used as BFD session in BFD group.

Figure 4 is a schematic diagram of a group configuration interface provided by an embodiment of the present application. As shown in Figure 4, the group configuration interface displays BFD group name options, BFD session configuration options, etc.

Among them, the BFD group name option is used by developers to enter the name of the BFD group. The BFD session configuration option allows developers to enter individual members of the BFD group.

When the first forwarding node detects that the developer triggers the BFD session configuration option through a preset operation, the first forwarding node can display the group member input form in Figure 4, which is used by the developer to input the group member input form in the BFD group. Individual BFD sessions. As shown in Figure 4, for the first forwarding node R1 shown in Figure 3, the developer enters BFD session 1, BFD session 2 and BFD session 3 in the group member input form, thereby realizing the integration of BFD session 1, BFD session 2 and As a member of the BFD group, BFD session 3 realizes the linkage between BFD session 1, BFD session 2 and BFD session 3. These three BFD sessions and the BFD group (BFD group).

It should be noted that the above configuration process is explained by taking the developer's configuration on the first forwarding node as an example. Optionally, the developer can also configure the BFD group on the first forwarding node on the control node of the network, and the control node delivers the configured BFD group to the first forwarding node. No further details will be given here.

In addition, the BFD group includes the BFD session of each of the multiple paths corresponding to the first forwarding node. Therefore, the state of the BFD group is correspondingly related to the state of the BFD session of each of the multiple paths. The status of the BFD group is explained in detail below.

In some embodiments, the status of the BFD group can indicate whether there is a BFD session in the BFD group that is in the closed state, or it can indicate whether all BFD sessions in the BFD group are in the closed state.

In this scenario, the relationship between the status of the BFD group and the status of each BFD session in the BFD group can be: when each BFD session in the BFD group is closed, the status of the BFD group is closed. Status; when the status of at least one BFD session in the BFD group is open, the status of the BFD group is open.

For example, for the first forwarding node R1 shown in Figure 1, when the multiple paths in step 201 are the three paths corresponding to segment service 2 marked in Figure 1, as shown in Figure 3, R1 to R6 The BFD session on the path from R1 to R5 is called BFD session 1, the BFD session on the path from R1 to R5 is called BFD session 2, and the BFD session on the path from R1 to R4 is called BFD session 3. That is, the BFD group includes BFD session 1, BFD session 2, and BFD session 3. When the status of BFD session 1, BFD session 2 and BFD session 3 are all closed, the status of the BFD group will be closed. There is at least one BFD in BFD session 1, BFD session 2 and BFD session 3. When the status of the session is open, the status of the BFD group is open.

In other embodiments, the status of the BFD group can indicate whether most BFD sessions in the BFD group are in the closed state, or, in other words, can indicate whether most of the BFD sessions in the BFD group are all in the closed state.

In this scenario, the relationship between the status of the BFD group and the status of each BFD session in the BFD group can be: pre-set a quantity threshold, and when all BFD sessions in the BFD group exceeding the quantity threshold are in a closed state , the status of the BFD group is closed; when the status of BFDs in the BFD group lower than the number threshold is closed, the status of the BFD group is open.

Among them, the quantity threshold is a value less than or equal to the number of BFD group members. The quantity threshold can be configured in advance by the administrator, and this is not limited in the embodiments of this application. In addition, "more than" in the embodiment of the present application can be understood as greater than or greater than or equal to, and "less than" can be understood as less than equal to or less than respectively, which is not limited in the embodiment of the present application.

For example, as shown in Figure 2, the BFD group includes BFD session 1, BFD session 2, and BFD session 3. When at least two BRDs in BFD session 1, BFD session 2, and BFD session 3 are all down, the status of the BFD group is down. In BFD session 1, BFD session 2, and BFD session 3 When at least two BFD sessions are open, the BFD group's status is open.

In the embodiment of the present application, when the status of the BFD group is the previous embodiment, the first forwarding node can predetermine and store the status of the BFD group, or it can also perform step 202 based on each status of the BFD group. The status of the BFD session is temporarily determined by the status of the BFD group. This is explained below.

In some embodiments, the implementation process of the first forwarding node pre-updating and storing the status of the BFD group may be: the first forwarding node obtains the BFD session status of each of the multiple paths; the first forwarding node based on the multiple paths The BFD session status of each path in the BFD group is updated and stored. In this scenario, in step 201, the first forwarding node obtains the status of the BFD group, which can be understood as: the first forwarding node obtains the stored status of the BFD group.

For a detailed implementation method for the first forwarding node to update the status of the BFD group based on the BFD session status of each path among the multiple paths, please refer to the related explanation of the BFD group status mentioned above and will not be described again here.

In addition, in this scenario, the timing for the first forwarding node to update and store the status of the BFD group in advance may be: the first forwarding node periodically updates and stores the status of the BFD group. For example, the first forwarding node performs an update every 10 ms and stores the status of the BFD group. Optionally, the first forwarding node may also update and store the status of the BFD group when detecting a change in the status of any BFD session in the BFD group.

In other embodiments, if the first forwarding node temporarily determines the status of the BFD group based on the status of each BFD session in the BFD group when performing step 202, the implementation process of step 201 may be: first forwarding The node obtains the BFD session status of each of the multiple paths; the first forwarding node determines the status of the BFD group based on the BFD session status of each of the multiple paths.

Wherein, the first forwarding node determines the status of the BFD group based on the BFD session status of each path among the multiple paths. The implementation method can also refer to the related explanation of the status of the BFD group mentioned above, which will not be described again here.

In addition, step 201 may be implemented by the control plane of the first forwarding node, or may be implemented by the forwarding plane of the first forwarding node.

It should be noted that the control plane and the forwarding plane are two planes that divide each hardware on the first forwarding node according to functional logic. Among them, the control plane usually includes the main control board and central processor, etc., and the forwarding plane usually includes various components that perform forwarding, such as forwarding entry memory, physical interface card, and network processor.

Based on this, step 201 is implemented by the control plane of the first forwarding node specifically means that the relevant operations in step 201 are performed by the central processor (or main control board) of the first forwarding node. Implementation of step 201 by the forwarding plane of the first forwarding node specifically means that the relevant operations in step 201 are performed by the network processor of the first forwarding node.

Since the packet flow is forwarded by the forwarding plane of the first forwarding node, when step 201 is executed by the forwarding plane of the first forwarding node, the second forwarding node can quickly sense the fault conditions of the multiple paths, thereby realizing cross-border transmission. Fast fault detection in segmented networks.

When step 201 is implemented by the forwarding plane of the first forwarding node, step 201 can be understood as: obtaining the status of the BFD group on the forwarding plane of the first forwarding node.

In addition, it should be noted that the above description is based on the example that the status of the BFD group and the status of each BFD session in the BFD group are independent concepts. Optionally, in other embodiments, the status of the BFD group may be directly the status of each BFD session in the BFD group. In this case, the first forwarding node obtains the status of the BFD group, which can be understood as obtaining the status of each BFD session in the BFD group. At this time, there is no execution action on the first forwarding node to determine the status of the BFD group based on the status of each BFD session in the BFD group.

Step 202: The first forwarding node notifies the second forwarding node of the fault conditions of multiple paths based on the status of the BFD group.

In this embodiment of the present application, the first forwarding node may notify the failure status of multiple paths through the following two implementation methods. This is explained separately below.

The first notification method: linking the upper-level BFD session for notification.

The upper-level BFD session is used to detect the failure of the path between the first forwarding node and the second forwarding node. In other words, the upper-level BFD session is the BFD session of the path between the first forwarding node and the second forwarding node. Specifically, it can be understood as a BFD session on the path between the outbound interface of the first forwarding node and the inbound interface of the second forwarding node.

The so-called linkage with the upper-level BFD session for notification means that the first forwarding node processes the upper-level BFD session based on the status of the BFD group, so that the upper-level BFD session can transmit fault conditions of multiple paths. This notification method can also be called "BFD session track group".

Among them, the BFD session can be a BFD session defined in request for comments (RFC) 5880, or a Seamless Bidirectional Forwarding Detection (SBFD) session defined in RFC7880.

BFD sessions defined in RFC5880 include BFD sessions in asynchronous mode and BFD sessions in query mode. A BFD session in asynchronous mode can be understood as: both parties send BFD packets (or BFD detection packets) to the opposite end, and the opposite end determines whether there is a fault in the path between the two parties based on the reception of BFD packets. The BFD session in query mode can be understood as: one end sends a BFD message to the other end, and the other end is only responsible for returning the BFD message. The part of sending the BFD message is based on the situation of receiving the BFD message returned by the other end to determine the two parties. Are there any faults in the path between them? Among them, in a BFD session in query mode, both parties in the session can be the end of sending BFD packets, that is, both parties in the session can initiate a BFD session in query mode.

It should be noted that in the BFD session defined by RFC5880, whether it is a BFD session in asynchronous mode or a BFD session in query mode, both parties in the session have the BFD session state, and the BFD session state includes four session states, namely closed (down) state, initial (init) state, open (up) state, administrative shutdown (admin-down) state.

The SBFD session defined in RFC7880 can be understood as: both parties in the session include a BFD initiator and a BFD reflector. The BFD initiator sends a BFD message (BFD control message) to the BFD reflector. The BFD reflector is only responsible for reflecting the BFD message. The BFD initiator determines the relationship between the two parties based on the BFD message returned by the BFD reflector. Whether the path is faulty.

It should be noted that for the SBFD session defined in RFC7880, only the BFD initiator has a BFD session state, and there are only two states: closed state and open state. The BFD reflection end does not have session status for this SBFD session. In addition, the BFD initiator and BFD reflector in the SBFD session are fixed. In other words, only one end can serve as the BFD initiator and the other end can serve as the BFD reflector. The roles of the two cannot be interchanged.

Based on the above description of the BFD session, the following is a detailed explanation of how to handle the upper-level BFD session in two situations.

Case 1: The upper-level BFD session is a BFD session in asynchronous mode.

In this scenario, the first forwarding node processes the upper-level BFD session based on the status of the BFD group. The implementation process can be: based on the status of the BFD group, the first forwarding node processes the upper-level BFD session. The process of sending information by the second forwarding node, or the process of processing the information from the second forwarding node in the upper-level BFD session, so that the upper-level BFD session can transmit the fault conditions of multiple paths.

The following explains the process of the first forwarding node sending information to the second forwarding node in processing an upper-level BFD session based on the status of the BFD group.

In some embodiments, based on the status of the BFD group, the implementation process of the first forwarding node processing the process of sending information to the second forwarding node in the upper-level BFD session may be: if the status of the BFD group is closed, the first The first forwarding node does not send the first BFD message to the second forwarding node. Correspondingly, if the status of the BFD group is open, the first forwarding node sends the first BFD message to the second forwarding node.

Because both parties in a BFD session in asynchronous mode periodically send BFD packets, the other end can determine whether there is a fault based on the reception of BFD packets. Therefore, when the first forwarding node periodically sends BFD packets to the second forwarding node, if it detects that the status of the BFD group is closed, it will no longer send BFD packets to the second forwarding node, so that the second forwarding node The node will detect that there is a fault in the upper-level BFD session, that is, it will detect that there is a fault on the first forwarding node, thereby passing the fault conditions of multiple paths to the first forwarding node through the upper-level BFD session, achieving cross-bundling Fault detection on segmented networks.

Optionally, the first delay length can be set, so that when the first forwarding node periodically sends BFD messages to the second forwarding node, when the current time is the time to send the first BFD message to the second forwarding node, , if it is detected that the status of the BFD group is closed, then determine whether the status of the BFD group is still closed after the first delay time. If it is still closed, the first forwarding node does not send the message to the second forwarding node. The first BFD packet. If after the first delay time, the status of the BFD group is open, at this time, the first BFD message is sent to the second forwarding node.

In this way, it can be avoided that the first forwarding node directly changes the path due to misjudgment of the BFD group status.

In other embodiments, based on the status of the BFD group, the first forwarding node processes the process of sending information to the second forwarding node in the upper-level BFD session as follows: if the status of the BFD group is closed, The first forwarding node sets the status of the upper-level BFD session to the closed state, and sends a status notification message to the second forwarding node. The status notification message indicates that the status of the upper-level BFD session is closed. Correspondingly, if the status of the BFD group is in the open state, the first forwarding node does not perform the operation of setting the upper-level BFD session status to the closed state.

In a BFD session in asynchronous mode, the first forwarding node has the ability to directly set the BFD session status to the closed state and advertise the BFD session status. Therefore, if the first forwarding node detects that the status of the BFD group is closed, it directly sets the status of the upper-level BFD session to the closed state, and sends a status notification message to the second forwarding node. In this way, the second forwarding node will It is detected that there is a fault in the upper-level BFD session, that is, it is detected that there is a fault on the first forwarding node, so that the fault conditions of multiple paths are passed to the first forwarding node through the upper-level BFD session, achieving cross-segment network fault detection.

Optionally, the delay length can also be set to avoid direct route change by the first forwarding node due to misjudgment of the BFD group status. The relevant implementation methods will not be described again here.

It should be noted that the above two embodiments are examples of processing information sent to the second forwarding node in an upper-level BFD session in a BFD group-based state. Any specific method for processing information sent to the second forwarding node in the upper-level BFD session is within the scope of the embodiments of this application as long as the following conditions are met. The condition is: when the BFD group status is in the closed state, the information sent can enable the second forwarding node to determine that the upper-level BFD session is faulty.

The following explains the processing flow of the first forwarding node processing the information from the second forwarding node in the upper-level BFD session based on the status of the BFD group.

In some embodiments, based on the status of the BFD group, the implementation process of the first forwarding node processing the information from the second forwarding node in the upper-level BFD session may be: after receiving the information from the second forwarding node When receiving the second BFD message, if the status of the BFD group is closed, the first forwarding node discards the second BFD message and does not update the number of BFD messages received in the current BFD detection cycle based on the second BFD message. operation. Correspondingly, if the status of the BFD group is open, the first forwarding node updates the number of BFD packets received in the current BFD detection cycle based on the second BFD packet.

It should be noted that the above embodiment is an example description of the processing flow of information from the second forwarding node in the upper-level BFD session in a state based on the BFD group. Any specific way of processing the information from the second forwarding node in the upper-level BFD session is within the scope of the embodiments of this application as long as the following conditions are met. The condition is: when the BFD group status is in the closed state, the processing flow of the information from the second forwarding node can enable the first forwarding node to determine that the status of the upper-level BFD session is in the closed state, and send the message to the second forwarding node. Send status notification messages.

The second case: the upper-level BFD session is a BFD session in query mode or a seamless bidirectional forwarding detection SBFD session.

When the upper-level BFD session is a BFD session in query mode or an SBFD session, one of the two parties in the upper-level BFD session is used to detect faults, and the other is only used to reflect the received BFD packets. In this scenario, in order to enable the second forwarding node to detect faults across segmented networks, the second forwarding node serves as the party that sends BFD packets, and the first forwarding node serves as the party that returns the received BFD packets.

In this scenario, the first forwarding node processes the upper-level BFD session based on the status of the BFD group. The first forwarding node processes the upper-level BFD session based on the status of the BFD group. The processing flow of BFD packets of the second forwarding node so that the upper-level BFD session can transmit the fault conditions of multiple paths.

Specifically, when receiving the third BFD message from the second forwarding node, if the status of the BFD group is closed, the first forwarding node discards the third BFD message and does not return the third BFD message. Operation to the second forwarding node. Correspondingly, if the status of the BFD group is open, the first forwarding node returns the third BFD packet to the second forwarding node.

The above description takes the BFD session defined in RFC5880 and the SBFD session defined in RFC7880 as examples. It should be noted that the specific process of "processing the upper-level BFD session" in the above two BFD session protocol scenarios can be applied to other possible BFD session protocols, and this application does not limit this in the embodiments.

In addition, in the embodiment of the present application, in order to be able to link the status of the BFD group with the upper-level BFD session, it can also be configured in advance by the developer.

In some embodiments, the developer configures the linkage between the status of the BFD group and the upper-level BFD session. The implementation process may be: the first forwarding node obtains the BFD group, and the first forwarding node determines the relationship between the BFD group and the upper-level BFD session. Correspondence between level BFD sessions.

Specifically, the first forwarding node displays a group configuration interface, and the group configuration interface includes a group tracking function configuration option; in response to the developer's trigger operation on the group tracking function configuration option, the upper-level BFD session and the BFD group Group binding to establish the corresponding relationship between the BFD group and the upper-level BFD session, and process the process of the upper-level BFD session based on the status of the BFD group.

Figure 5 is a schematic diagram of another group configuration interface provided by an embodiment of the present application. As shown in Figure 5, the group configuration interface displays BFD group name options, BFD session configuration options, and group tracking function configuration options.

Among them, the BFD group name option and BFD session configuration option have been explained previously and will not be described again here. The group tracking function configuration option is used by developers to link the status of the BFD group with the upper-level BFD session.

When the first forwarding node detects that the developer triggers the group tracking function configuration option through a preset operation, the first forwarding node can display the tracking session input window in Figure 5. The tracking session input window is used for the developer to input and communicate with the BFD group. The upper-level BFD session associated with the group. As shown in Figure 5, for the first forwarding node R1 shown in Figure 2, the developer enters the identifier of the upper-level BFD session in the tracking session input window, thereby realizing BFD session 1, BFD session 2 and BFD session 3. Linkage between BFD group and upper-level BFD session.

It should be noted that the above configuration process is explained by taking the developer's configuration on the first forwarding node as an example. Optionally, developers can also configure an upper-level BFD session on the control node of the network that is associated with the BFD group on the first forwarding node, and the control node downloads the corresponding relationship between the BFD group and the previous BFD. Sent to the first forwarding node. No further details will be given here.

In addition, when the status of the BFD group is directly the status of each BFD session in the BFD group, for the specific content of the status of the BFD group being closed, please refer to the above-mentioned explanation of the BFD status. For example, when the status of the BFD group indicates whether the status of all members in the BFD group is closed, the status of the BFD group is closed, that is, the status of each BFD session in the BFD group is closed. state. The status of the BFD group is open, that is, the status of at least one BFD session in the BFD group is open.

For example, in the first case and the second case, when the first forwarding node obtains the status of each BFD session in the BFD group, if it determines that the status of each BFD session in the BFD group is closed, then When the current time is the time to send the first BFD message to the second forwarding node, the first forwarding node does not send the first BFD message to the second forwarding node, or the first forwarding node replaces the first BFD message of the upper-level BFD session with the second forwarding node. The status is set to the closed state and a status notification message is sent to the second forwarding node. Alternatively, when receiving the third BFD packet from the second forwarding node, the first forwarding node discards the third BFD packet and does not execute the The operation of returning the third BFD packet to the second forwarding node. For specific implementation methods, please refer to the foregoing content and will not be described again here.

In addition, in the first notification method, since the upper-level BFD session is linked for notification, there is no need to add other transmission content between the first forwarding node and the second forwarding node. This notification method is easy to implement and saves network resources. .

In addition, messages related to the upper-level BFD session are forwarded on the forwarding plane of the first forwarding node. Therefore, by linking the upper-level BFD session, the entire fault detection process can be implemented on the forwarding plane of the first forwarding node, thus improving the fault detection rate.

The second notification method: notification via notification message.

The notification message refers to the first forwarding node notifying the second forwarding node of the status of the BFD group through a special message. In this scenario, the implementation process of step 202 is as follows: the first forwarding node sends a fault notification message to the second forwarding node, and the fault notification message is used to notify the second forwarding node of fault conditions of multiple paths.

The fault notification message can notify fault conditions of multiple paths in multiple ways. In some embodiments, the fault notification message carries the status of the BFD group. Optionally, the fault notification message may also carry other indication information, and the other indication information can identify fault conditions of multiple paths.

In this embodiment of the present application, the fault notification message can be carried in the service traffic or in a special BGP notification message (that is, notified through the BGP protocol). Specific Implementation Mode The embodiments of this application will not describe this in detail.

When the fault notification message is carried in the service traffic, step 202 can be understood as notifying the fault situation of multiple paths to the second forwarding node based on the status of the BFD group on the forwarding plane of the first forwarding node.

When the fault notification message is carried in a special BGP notification message, the BGP notification message can be implemented on the forwarding plane or the control plane. Therefore, step 202 may be: notifying the second forwarding node of the fault conditions of the multiple paths based on the status of the BFD group on the forwarding plane of the first forwarding node, or, based on the BFD group on the control plane of the first forwarding node. The status notifies the second forwarding node of the failure conditions of multiple paths.

To sum up, the technical solutions provided by the embodiments of this application can achieve the following technical effects:

(1) Provides a method to implement multi-point fault detection across segmented networks based on BFD groups. There is no need to deploy BFD sessions based on routes to detect multiple points of failure. Provides the flexibility of multi-point failure detection across segmented networks.

(2) Link the BFD group with the upper-level BFD session, and quickly trigger the upper-level BFD down based on the status of the BFD group, so as to pass the fault detected based on the BFD group to the upper-level segmented network, so that It can speed up traffic switching and reduce packet loss.

(3) The entire fault sensing process can be implemented on the forwarding plane, which improves the fault sensing rate.

Taking the communication system shown in Figure 3 as an example, the embodiment shown in Figure 2 will be explained again below.

Based on the communication system shown in Figure 3, the fault detection process across segmented networks can be implemented through the following steps.

Step 1: Deploy multiple basic BFD sessions (BFD session 1, BFD session 2, and BFD session 3) for detecting segmented services on the cascade device R1 in the segmented cascade network. Among them, the session type of BFD session includes all BFD session types;

Step 2: Create a group (i.e. BFD group) on the cascading device R1, and deliver the group status on the forwarding plane of R1;

Step 3: Add multiple basic BFD sessions BFD session 1, BFD session 2, and BFD session 3 on the cascade device R1 to the group;

Step 4: Deploy the upper-level segment network on the cascade device R1 to detect the BFD track group of segment service 1 (that is, the BFD session track group defined in RFC5880) or the SBFD reflection end track group;

Step 5: Refresh the group status according to the status of the basic BFD session on the forwarding plane. The refresh rules are as follows: As long as one basic BFD session forwarding plane status is up, the group status is up, and the forwarding plane status of all basic BFD sessions is down. The group status is down;

Step 6: If a BFD track group is deployed in step 4, the group status is determined during the BFD session packet sending or receiving process. If the group status is down, the received BFD packets are not sent or discarded or the BFD session is set up directly. The status is down, triggering the remote end (i.e. R2) to detect down;

Step 7: If the SBFD reflection end track group is deployed in step 4, the group status is determined during the SBFD reflection process. If the group status is down, the received BFD packet is discarded and the SBFD initiator, that is, R2) detection is triggered. down;

Step 8: After the remote end or SBFD initiator (i.e. R2) goes down, trigger service switching.

Figure 6 is a schematic structural diagram of a network device provided by an embodiment of the present application. The network device is the first forwarding node in the communication system shown in Figure 1. As shown in Figure 1, the communication system also includes a second forwarding node. , the first forwarding node is an edge node between the first segmented network and the second segmented network, and the second forwarding node is located within the first segmented network. Specifically, as shown in Figure 6, the network device 600 includes a transceiver module 601 and a processing module 602.

Among them, the transceiver module 602 is used to perform transceiver-related operations in the embodiment of FIG. 2; the processing module 601 is used to perform operations other than transceiver-related operations in the embodiment of FIG. 2.

Specifically, the processing module 602 is used to obtain the status of the bidirectional forwarding detection BFD group. The BFD group includes the BFD session of each of the multiple paths corresponding to the first forwarding node in the second segmented network. The BFD session is To detect the failure of the corresponding path. For specific implementation, please refer to step 201 in the embodiment of Figure 2 .

The transceiver module 601 is configured to notify the second forwarding node of fault conditions of multiple paths based on the status of the BFD group. For specific implementation, please refer to step 202 in the embodiment of Figure 2 .

Optionally, when each BFD session in the BFD group is in a closed state, the status of the BFD group obtained by the processing module is a closed state;

When the status of at least one BFD session in the BFD group is open, the status of the BFD group obtained by the processing module is open.

Optionally, the transceiver module is used for:

The first forwarding node processes the process of an upper-level BFD session based on the status of the BFD group. The upper-level BFD session is used to detect a failure of the path between the first forwarding node and the second forwarding node.

Optionally, the transceiver module is used for:

If the status of the BFD group is closed, the first forwarding node does not send the first BFD message to the second forwarding node.

Optionally, the transceiver module is used for:

If the status of the BFD group is open, the first forwarding node sends the first BFD message to the second forwarding node.

Optionally, the transceiver module is used for:

If the status of the BFD group is closed, the first forwarding node sets the status of the upper-level BFD session to closed and sends a status notification message to the second forwarding node. The status notification message indicates the status of the upper-level BFD session. is closed.

Optionally, the transceiver module is used for:

If the status of the BFD group is open, the first forwarding node does not perform the operation of setting the upper-level BFD session status to the closed state.

Optionally, the transceiver module is used for:

When receiving the second BFD message from the second forwarding node, if the status of the BFD group is closed, the first forwarding node discards the second BFD message and does not update the current BFD detection based on the second BFD message. Operation of the number of BFD packets received in a period.

Optionally, the transceiver module is used for:

If the status of the BFD group is open, the first forwarding node updates the number of BFD packets received in the current BFD detection cycle based on the second BFD packet.

Optionally, the transceiver module is used for:

When receiving the third BFD packet from the second forwarding node, if the status of the BFD group is closed, the first forwarding node discards the third BFD packet and does not return the third BFD packet to the second forwarding node. Operations of forwarding nodes.

Optionally, the transceiver module is used for:

If the status of the BFD group is open, the first forwarding node returns the third BFD packet to the second forwarding node.

Optionally, the upper-level BFD session is a BFD session in asynchronous mode, a BFD session in query mode, or a seamless bidirectional forwarding detection SBFD session.

Optionally, the processing module is also used to:

The first forwarding node obtains the BFD group;

The first forwarding node determines the corresponding relationship between the BFD group and the upper-level BFD session.

Optionally, the transceiver module is also used to:

The first forwarding node sends a fault notification message to the second forwarding node, and the fault notification message is used to notify the second forwarding node of fault conditions of multiple paths.

Optionally, the fault notification message carries the status of the BFD group.

Optionally, the processing module is also used to:

Periodically obtain the BFD session status of each path in multiple paths;

Based on the BFD session status of each path in multiple paths, periodically update and store the status of the BFD group;

Get the status of the stored BFD group.

Optionally, the processing module is used to:

Get the BFD session status of each path in multiple paths;

The status of the BFD group is determined based on the BFD session status of each of the multiple paths.

Optionally, multiple paths are used to forward the message flow from the second forwarding node.

Optionally, the first segmented network and the second segmented network are respectively used to carry at least one of the following services: segmented routing policy SRv6 Policy service based on the sixth generation network protocol, SRv6 Policy service based on the sixth generation network protocol The shortest path SRv6 BE service of segment routing, the virtual leased line VLL service, and the virtual private line service VPLS service; the services carried by the first segment network are different from the services carried by the second segment network.

Optionally, the processing module is used to:

Obtain the status of the BFD group on the forwarding plane of the first forwarding node.

Optionally, the transceiver module is used for:

On the forwarding plane of the first forwarding node, the fault conditions of the multiple paths are notified to the second forwarding node based on the status of the BFD group.

To sum up, the network equipment provided by the embodiments of this application can achieve the following technical effects:

The hardware structure involved in the embodiment of this application is introduced below.

Figure 7 is a schematic structural diagram of a device 700 provided by an embodiment of the present application. Figure 8 is a schematic structural diagram of another device 800 provided by an embodiment of the present application. The structure of these two devices is explained below.

It should be noted that the device 700 or device 800 introduced below corresponds to the first forwarding node in the above method embodiment. Each hardware, module and the above-mentioned other operations and/or functions in the device 700 or the device 800 are respectively used to implement the various steps and methods implemented by the first forwarding node in the method embodiment. Regarding how the device 700 or the device 800 processes messages, For the detailed process, please refer to the above method embodiments for specific details. For the sake of simplicity, they will not be described again here. Each step of the above method embodiment is completed through the integrated logic circuit of the hardware in the processor of the device 700 or the device 800 or instructions in the form of software. The steps of the methods disclosed in conjunction with the embodiments of the present application can be directly implemented by a hardware processor for execution, or can be executed by a combination of hardware and software modules in the processor. The software module can be located in random access memory, flash memory, read-only memory, programmable read-only memory or electrically erasable programmable memory, registers and other mature storage media in this field. The storage medium is located in the memory, and the processor reads the information in the memory and completes the steps of the above method in combination with its hardware. To avoid repetition, the details will not be described here.

When the device 700 corresponds to the above-mentioned first forwarding node, each functional module in the first forwarding node is implemented using the software of the device 700 . In other words, the functional module included in the first forwarding node is generated by the processor of the device 700 after reading the program code stored in the memory.

When the device 800 corresponds to the above-mentioned first forwarding node, each functional module in the first forwarding node is implemented using the software of the device 800 . In other words, the functional module included in the first forwarding node is generated by the processor of the device 800 after reading the program code stored in the memory.

Referring to FIG. 7 , FIG. 7 is a schematic structural diagram of a device 700 provided by an embodiment of the present application. Optionally, the device 700 is configured as the first forwarding node shown in Figure 1. In other words, the first forwarding node in the above method embodiment is optionally implemented by the device 700.

The device 700 is, for example, a network device. For example, the device 700 is a switch, a router, etc. Alternatively, the device 700 is, for example, a computing device. For example, the device 700 is a host, a server or a personal computer. The device 700 can be implemented by a general bus architecture.

Device 700 includes at least one processor 701, a communication bus 702, a memory 703, and at least one communication interface 704.

The processor 701 is, for example, a general central processing unit (CPU), a network processor (NP), a graphics processor (Graphics Processing Unit, GPU), or a neural network processor (neural-network processing units, NPU). ), a data processing unit (Data Processing Unit, DPU), a microprocessor or one or more integrated circuits used to implement the solution of this application. For example, the processor 701 includes an application-specific integrated circuit (ASIC), a programmable logic device (PLD), or a combination thereof. PLD is, for example, a complex programmable logic device (CPLD), a field-programmable gate array (FPGA), a general array logic (GAL), or any combination thereof.

Communication bus 702 is used to transfer information between the above-mentioned components. The communication bus 702 can be divided into an address bus, a data bus, a control bus, etc. For ease of presentation, only one thick line is used in Figure 7, but this does not mean that there is only one bus or one type of bus.

The memory 703 is, for example, a read-only memory (ROM) or other type of static storage device that can store static information and instructions, or a random access memory (random access memory, RAM) or a device that can store information and instructions. Other types of dynamic storage devices, such as electrically erasable programmable read-only memory (EEPROM), compact disc read-only memory (CD-ROM) or other optical disk storage, optical discs Storage (including compressed optical discs, laser discs, optical discs, digital versatile discs, Blu-ray discs, etc.), magnetic disk storage media or other magnetic storage devices, or can be used to carry or store desired program code in the form of instructions or data structures and can Any other media accessed by a computer, without limitation. The memory 703 exists independently, for example, and is connected to the processor 701 through the communication bus 702 . Memory 703 may also be integrated with processor 701.

Communication interface 704 uses any transceiver-like device for communicating with other devices or communication networks. The communication interface 704 includes a wired communication interface and may also include a wireless communication interface. The wired communication interface may be an Ethernet interface, for example. The Ethernet interface can be an optical interface, an electrical interface, or a combination thereof. The wireless communication interface may be a wireless local area networks (WLAN) interface, a cellular network communication interface or a combination thereof.

In specific implementation, as an embodiment, the processor 701 may include one or more CPUs, such as CPU0 and CPU1 shown in FIG. 7 .

In specific implementation, as an embodiment, the device 700 may include multiple processors, such as the processor 701 and the processor 705 shown in FIG. 7 . Each of these processors can be a single-core processor (single-CPU) or a multi-core processor (multi-CPU). A processor here may refer to one or more devices, circuits, and/or processing cores for processing data (such as computer program instructions).

In specific implementation, as an embodiment, the device 700 may also include an output device and an input device. Output devices communicate with processor 701 and can display information in a variety of ways. For example, the output device may be a liquid crystal display (LCD), a light emitting diode (LED) display device, a cathode ray tube (CRT) display device, or a projector (projector), etc. Input devices communicate with processor 701 and can receive user input in a variety of ways. For example, the input device may be a mouse, a keyboard, a touch screen device or a sensing device, etc.

In some embodiments, the memory 703 is used to store the program code 710 for executing the solution of the present application, and the processor 701 can execute the program code 710 stored in the memory 703. That is, the device 700 can implement the fault detection method across segmented networks provided by the method embodiment through the processor 701 and the program code 710 in the memory 703 .

The device 700 in the embodiment of the present application can correspond to the user plane network element or the control plane network element in the above method embodiments, and the processor 701, communication interface 704, etc. in the device 700 can implement the above method embodiments. The functions possessed by the first forwarding node and/or the various steps and methods implemented. For the sake of brevity, no further details will be given here.

In the case where fault detection across segmented networks is implemented using the device 700, in some embodiments, the transceiver module and the processing module in the network device 600 shown in Figure 6 are software modules in the program code 710 in the device 700 , the processor 701 in the device 700 implements the functions of the transceiver module and the processing module in the network device 600 in Figure 6 by executing the program code 710.

Referring to FIG. 8 , FIG. 8 is a schematic structural diagram of a device 800 provided by an embodiment of the present application. Optionally, the device 800 is configured as the first forwarding node shown in FIG. 1 . In other words, the first forwarding node in the above method embodiment is optionally implemented by the device 800.

The device 800 is, for example, a network device. For example, the device 800 is a switch, a router, etc. The device 800 includes: a main control board 8010 and an interface board 8030.

The main control board is also called the main processing unit (MPU) or route processor card. The main control board 8010 is used to control and manage various components in the device 800, including route calculation, device management, Equipment maintenance and protocol processing functions. The main control board 8010 includes: a central processing unit 8011 and a memory 8012.

The interface board 8030 is also called a line processing unit (LPU), line card or service board. The interface board 8030 is used to provide various service interfaces and implement data packet forwarding. Business interfaces include but are not limited to Ethernet interfaces, POS (Packet over SONET/SDH) interfaces, etc. Ethernet interfaces are, for example, Flexible Ethernet Clients (FlexE Clients). The interface board 8030 includes: a central processor 8031, a network processor 8032, a forwarding entry memory 8034, and a physical interface card (PIC) 8033.

The central processor 8031 on the interface board 8030 is used to control and manage the interface board 8030 and communicate with the central processor 8011 on the main control board 8010.

The network processor 8032 is used to implement packet forwarding processing. The network processor 8032 may be in the form of a forwarding chip. Specifically, the network processor 8032 is used to forward the received message based on the forwarding table stored in the forwarding table memory 8034. If the destination address of the message is the address of the device 800, the message is uploaded to the CPU (such as Central processor 8011) processes; if the destination address of the message is not the address of device 800, the next hop and outbound interface corresponding to the destination address are found from the forwarding table based on the destination address, and the message is forwarded to the destination. The outbound interface corresponding to the address. Among them, the processing of uplink packets includes: processing of packet incoming interfaces, forwarding table search; processing of downlink packets: forwarding table search, etc.

The physical interface card 8033 is used to implement the docking function of the physical layer. The original traffic enters the interface card 8030 through this, and the processed packets are sent out from the physical interface card 8033. The physical interface card 8033 is also called a daughter card and can be installed on the interface board 8030. It is responsible for converting photoelectric signals into messages and checking the validity of the messages before forwarding them to the network processor 8032 for processing. In some embodiments, the central processor can also perform the functions of the network processor 8032, such as implementing software forwarding based on a general-purpose CPU, so that the network processor 8032 is not required in the physical interface card 8033.

Optionally, the device 800 includes multiple interface boards. For example, the device 800 also includes an interface board 8040. The interface board 8040 includes: a central processor 8041, a network processor 8042, a forwarding entry memory 8044, and a physical interface card 8043.

Optionally, the device 800 also includes a switching network board 8020. The switching fabric unit 8020 can also be called a switching fabric unit (switch fabric unit, SFU). When the network device has multiple interface boards 8030, the switching network board 8020 is used to complete data exchange between the interface boards. For example, the interface board 8030 and the interface board 8040 can communicate through the switching network board 8020.

The main control board 8010 and the interface board 8030 are coupled. For example. The main control board 8010, the interface board 8030, the interface board 8040, and the switching network board 8020 are connected to the system backplane through the system bus to achieve intercommunication. In a possible implementation, an inter-process communication protocol (IPC) channel is established between the main control board 8010 and the interface board 8030, and the main control board 8010 and the interface board 8030 communicate through the IPC channel.

Logically, device 800 includes a control plane and a forwarding plane. The control plane includes a main control board 8010 and a central processor 8031. The forwarding plane includes various components that perform forwarding, such as forwarding entry memory 8034, physical interface card 8033, and network processor. 8032. The control plane executes functions such as router, generates forwarding tables, processes signaling and protocol messages, configures and maintains device status. The control plane sends the generated forwarding tables to the forwarding plane. On the forwarding plane, the network processor 8032 is based on the control plane. The delivered forwarding table looks up the packets received by the physical interface card 8033 and forwards them. The forwarding table delivered by the control plane may be stored in the forwarding table item storage 8034. In some embodiments, the control plane and forwarding plane may be completely separate and not on the same device.

In the case where the first forwarding node is implemented by the device 800, in some embodiments, the transceiver module in the network device 600 shown in Figure 6 is equivalent to the physical interface card 8033 in the device 800; the processing module of the network device 600 is equivalent to In the network processor 8032, the central processing unit 8031 or the central processing unit 8011.

It should be understood that the operations on the interface board 8040 in the embodiment of the present application are consistent with the operations on the interface board 8030, and will not be described again for the sake of simplicity. It should be understood that the device 800 in this embodiment can correspond to the first forwarding node in the above method embodiments, and the main control board 8010, interface board 8030 and/or 8040 in the device 800 can implement the above method embodiments. For the sake of brevity, the functions of the first forwarding node and/or the various steps performed will not be described again here.

It is worth mentioning that there may be one or more main control boards, and when there are multiple main control boards, they can include the main main control board and the backup main control board. There may be one or more interface boards. The stronger the data processing capability of the network device, the more interface boards are provided. There can also be one or more physical interface cards on the interface board. There may be no switching network board, or there may be one or more switching network boards. When there are multiple switching network boards, load sharing and redundant backup can be realized together. Under the centralized forwarding architecture, network equipment does not need switching network boards, and the interface boards are responsible for processing the business data of the entire system. Under the distributed forwarding architecture, network equipment can have at least one switching network board, which enables data exchange between multiple interface boards through the switching network board, providing large-capacity data exchange and processing capabilities. Therefore, the data access and processing capabilities of network equipment with a distributed architecture are greater than those with a centralized architecture. Optionally, the network device can also be in the form of only one board, that is, there is no switching network board. The functions of the interface board and the main control board are integrated on this board. In this case, the central processor and main control board on the interface board The central processor on the board can be combined into one central processor on this board to perform the superimposed functions of the two. This form of equipment has low data exchange and processing capabilities (for example, low-end switches or routers and other networks equipment). The specific architecture used depends on the specific networking deployment scenario and is not limited here.

In other embodiments, embodiments of the present application also provide a communication system. As shown in Figure 9, the communication system 900 includes a first forwarding node 901 and a second forwarding node 902.

Among them, the first forwarding node 901 is used to: obtain the status of the bidirectional forwarding detection BFD group. The BFD group includes the BFD session of each of the multiple paths corresponding to the first forwarding node in the second segment network. The BFD session Used to detect failures of corresponding paths; notify the second forwarding node 902 of the failure conditions of multiple paths based on the status of the BFD group.

For the detailed functions of each forwarding node in the above communication system, reference can be made to the embodiment shown in Figure 2 and will not be described again here.

Those of ordinary skill in the art can appreciate that the method steps and modules described in conjunction with the embodiments disclosed herein can be implemented by electronic hardware, computer software, or a combination of both. In order to clearly illustrate the possible functions of hardware and software, Interchangeability, in the above description, the steps and compositions of each embodiment have been generally described according to functions. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. One of ordinary skill in the art may implement the described functionality using different methods for each specific application, but such implementations should not be considered beyond the scope of this application.

Those skilled in the art can clearly understand that for the convenience and simplicity of description, the specific working processes of the systems, devices and modules described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be described again here.

In the several embodiments provided in this application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only illustrative. For example, the division of the modules is only a logical function division. In actual implementation, there may be other division methods. For example, multiple modules or components may be combined or may be Integrated into another system, or some features can be ignored, or not implemented. In addition, the coupling or direct coupling or communication connection between each other shown or discussed may be indirect coupling or communication connection through some interfaces, devices or modules, or may be electrical, mechanical or other forms of connection.

The modules described as separate components may or may not be physically separated. The components shown as modules may or may not be physical modules, that is, they may be located in one place, or they may be distributed to multiple network modules. Some or all of the modules can be selected according to actual needs to achieve the purpose of the embodiments of the present application.

In addition, each functional module in each embodiment of the present application can be integrated into one processing module, or each module can exist physically alone, or two or more modules can be integrated into one module. The above integrated modules can be implemented in the form of hardware or software function modules.

If the integrated module is implemented in the form of a software function module and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application is essentially or contributes to the existing technology, or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium , including several instructions to cause a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods in various embodiments of the present application. The aforementioned storage media include: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), magnetic disk or optical disk and other media that can store program code. .

In this application, the terms "first" and "second" are used to distinguish the same or similar items with basically the same functions and functions. It should be understood that there is no logic or timing between "first" and "second" There are no restrictions on the number and execution order of the dependencies. It should also be understood that, although the following description uses the terms first, second, etc. to describe various elements, these elements should not be limited by the terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of various examples, the first information may be referred to as second information, and similarly, the second information may be referred to as first information. Both the first information and the second information may be information, and in some cases, may be separate and different information.

The term "at least one" in this application means one or more, and the term "plurality" in this application means two or more. The terms "system" and "network" are often used interchangeably in this article.

It should also be understood that the term "if" may be interpreted to mean "when" or "upon" or "in response to determining" or "in response to detecting." Similarly, depending on the context, the phrase "if it is determined..." or "if [stated condition or event] is detected" may be interpreted to mean "when it is determined..." or "in response to the determination... ” or “on detection of [stated condition or event]” or “in response to detection of [stated condition or event].”

The above description is only a specific implementation mode of the present application, but the protection scope of the present application is not limited thereto. Any person familiar with the technical field can easily think of various equivalent modifications within the technical scope disclosed in the present application. Or replacement, these modifications or replacements should be covered by the protection scope of this application. Therefore, the protection scope of this application should be subject to the protection scope of the claims.

In the above embodiments, it may be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented using software, it may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer program instructions. When the computer program instructions are loaded and executed on a computer, the processes or functions according to the embodiments of the present application are generated in whole or in part. The computer may be a general purpose computer, a special purpose computer, a computer network, or other programmable device. The computer instructions may be stored in or transmitted from one computer-readable storage medium to another, e.g., the computer program instructions may be transmitted from a website, computer, server or data center to Wired or wireless transmission to another website site, computer, server or data center. The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device such as a server or data center integrated with one or more available media. The available media may be magnetic media (such as floppy disks, hard disks, magnetic tapes), optical media (such as digital video discs (DVD)), or semiconductor media (such as solid state drives), etc.

Those of ordinary skill in the art can understand that all or part of the steps to implement the above embodiments can be completed by hardware, or can be completed by instructing the relevant hardware through a program. The program can be stored in a computer-readable storage medium. As mentioned above, The storage medium can be read-only memory, magnetic disk or optical disk, etc.

The above descriptions are only optional embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application. within.

Claims

A fault detection method across segmented networks, characterized in that the method is applied to a communication system, the communication system includes a first forwarding node and a second forwarding node, the first forwarding node is the first segmented network and an edge node between the second segmented network, the second forwarding node being located within the first segmented network; the method includes:

The first forwarding node obtains the status of the bidirectional forwarding detection BFD group, where the BFD group includes the BFD session of each of the multiple paths corresponding to the first forwarding node in the second segmented network, The BFD session is used to detect the failure of the corresponding path;

The first forwarding node notifies the second forwarding node of the fault conditions of the multiple paths based on the status of the BFD group.
The method of claim 1, wherein the first forwarding node obtains the status of the BFD group, including:

When each BFD session in the BFD group is in a closed state, the status of the BFD group obtained by the first forwarding node is a closed state;

When the status of at least one BFD session in the BFD group is an open state, the status of the BFD group acquired by the first forwarding node is an open state.
The method of claim 1 or 2, wherein the first forwarding node notifies the second forwarding node of the fault conditions of the multiple paths based on the status of the BFD group, including:

The first forwarding node processes a process of an upper-level BFD session based on the status of the BFD group. The upper-level BFD session is used to detect the connection between the first forwarding node and the second forwarding node. Path failure.
The method of claim 3, wherein the first forwarding node processes the upper-level BFD session based on the status of the BFD group, including:

If the status of the BFD group is a closed state, the first forwarding node does not send the first BFD message to the second forwarding node.
The method of claim 4, wherein the first forwarding node processes the upper-level BFD session based on the status of the BFD group, including:

If the status of the BFD group is open, the first forwarding node sends the first BFD message to the second forwarding node.
The method of claim 3, wherein the first forwarding node processes the upper-level BFD session based on the status of the BFD group, including:

If the status of the BFD group is in the closed state, the first forwarding node sets the status of the upper-level BFD session to the closed state, and sends a status notification message to the second forwarding node. The notification message indicates that the status of the upper-level BFD session is closed.
The method of claim 6, wherein the first forwarding node processes the upper-level BFD session based on the status of the BFD group, including:

If the state of the BFD group is an open state, the first forwarding node does not perform an operation of setting the upper-level BFD session state to a closed state.
The method of claim 3, wherein the first forwarding node processes the upper-level BFD session based on the status of the BFD group, including:

When receiving the second BFD message from the second forwarding node, if the status of the BFD group is closed, the first forwarding node discards the second BFD message and does not perform the execution based on the second BFD message. The second BFD message updates the number of BFD messages received in the current BFD detection cycle.
The method of claim 8, wherein the first forwarding node processes the upper-level BFD session based on the status of the BFD group, including:

If the status of the BFD group is open, the first forwarding node updates the number of BFD packets received in the current BFD detection period based on the second BFD packet.
The method of claim 3, wherein the first forwarding node processes the upper-level BFD session based on the status of the BFD group, including:

When receiving the third BFD message from the second forwarding node, if the status of the BFD group is closed, the first forwarding node discards the third BFD message and does not execute the The operation of returning the third BFD packet to the second forwarding node.
The method of claim 10, wherein the first forwarding node processes the upper-level BFD session based on the status of the BFD group, including:

If the status of the BFD group is open, the first forwarding node returns the third BFD packet to the second forwarding node.
The method according to any one of claims 3-11, characterized in that the upper-level BFD session is a BFD session in asynchronous mode, a BFD session in query mode or a seamless bidirectional forwarding detection SBFD session.
The method according to any one of claims 3-12, characterized in that the method further includes:

The first forwarding node obtains the BFD group;

The first forwarding node determines the corresponding relationship between the BFD group and the upper-level BFD session.
The method of claim 1 or 2, wherein the first forwarding node notifies the second forwarding node of the fault conditions of the multiple paths based on the status of the BFD group, including:

The first forwarding node sends a fault notification message to the second forwarding node, where the fault notification message is used to notify the second forwarding node of fault conditions of the multiple paths.
The method of claim 14, wherein the fault notification message carries the status of the BFD group.
The method according to any one of claims 1 to 15, characterized in that before the first forwarding node obtains the status of the BFD group, the method further includes:

The first forwarding node periodically obtains the BFD session status of each of the multiple paths;

The first forwarding node periodically updates and stores the status of the BFD group based on the BFD session status of each of the multiple paths;

The first forwarding node obtains the status of the BFD group, including:

The first forwarding node obtains the stored status of the BFD group.
The method according to any one of claims 1 to 15, characterized in that the first forwarding node obtains the status of the BFD group, including:

The first forwarding node obtains the BFD session status of each of the multiple paths;

The first forwarding node determines the status of the BFD group based on the BFD session status of each of the multiple paths.
The method according to any one of claims 1 to 17, characterized in that the plurality of paths are used to forward message flows from the second forwarding node.
The method according to any one of claims 1 to 18, characterized in that the first segmented network and the second segmented network are respectively used to carry at least one of the following services: based on the sixth generation network The protocol's segment routing policy SRv6Policy service, the shortest path SRv6 BE service of segment routing based on the sixth generation network protocol, the virtual leased line VLL service, and the virtual private line service VPLS service;

The services carried by the first segmented network are different from the services carried by the second segmented network.
The method according to any one of claims 1 to 19, characterized in that the first forwarding node obtains the status of the BFD group, including:

Obtain the status of the BFD group on the forwarding plane of the first forwarding node.
The method according to any one of claims 1 to 20, characterized in that the first forwarding node notifies the second forwarding node of the fault conditions of the multiple paths based on the status of the BFD group, including:

On the forwarding plane of the first forwarding node, the failure conditions of the multiple paths are notified to the second forwarding node based on the status of the BFD group.
A communication system, characterized in that the system includes a first forwarding node and a second forwarding node, and the first forwarding node is used to perform the method according to any one of claims 1-21.
A network device, characterized in that the network device includes a memory and a processor;

The memory is used to store program instructions;

The processor is configured to call a program stored in the memory, so that the network device executes the method according to any one of claims 1-21.
A network device, characterized in that the network device is a first forwarding node in a communication system, the communication system further includes a second forwarding node, and the first forwarding node is a first segmented network and a second segmented network. An edge node between segmented networks, the second forwarding node is located within the first segmented network;

The network device includes a transceiver module and a processing module:

The transceiver module is used to perform transceiver-related operations in the method of any one of claims 1-21;

The processing module is configured to perform operations other than the transceiver-related operations in the method of any one of claims 1-21.
A computer-readable storage medium, characterized in that instructions are stored in the computer-readable storage medium, and when the instructions are run on a processor, the method described in any one of claims 1-21 is implemented.
A computer program product, characterized in that the computer program product contains instructions, and when the instructions are run on a processor, the method of any one of claims 1-21 is implemented.