CN113938446B

CN113938446B - Multicast table item synchronization method and device based on MLAG environment

Info

Publication number: CN113938446B
Application number: CN202111115608.5A
Authority: CN
Inventors: 潘天宇
Original assignee: Inspur Cisco Networking Technology Co Ltd
Current assignee: Inspur Cisco Networking Technology Co Ltd
Priority date: 2021-09-23
Filing date: 2021-09-23
Publication date: 2024-05-14
Anticipated expiration: 2041-09-23
Also published as: CN113938446A

Abstract

The embodiment of the specification discloses a multicast table item synchronization method and equipment based on an MLAG environment, wherein the method comprises the following steps: when the appointed equipment accesses the multicast group, the MLAG equipment receives IGMPreport messages sent by the appointed equipment; after receiving the IGMP report message, the MLAG device sets the entry state of the MLAG device from an initial state to a first state, and generates a multicast MAC entry according to the IGMP report message, wherein in the initial state, any device is not accessed at a designated port where the MLAG device receives the IGMP report message; in the first state, specific information of the IGMP report message is sent to the opposite terminal equipment through the Peer-link, so that the opposite terminal equipment sets the table entry state from the initial state to the second state after receiving the specific information, and in the second state, the opposite terminal equipment generates a multicast MAC table entry according to the specific information of the IGMP report message, so that the synchronous multicast MAC table entry in the MLAG equipment and the opposite terminal equipment is realized, and the appointed equipment is ensured to normally receive multicast group flow.

Description

Multicast table item synchronization method and device based on MLAG environment

Technical Field

The present disclosure relates to the field of network communications technologies, and in particular, to a method and an apparatus for synchronizing multicast table entries based on an MLAG environment.

Background

The cross-device Link Aggregation (MLAG) technology is to aggregate interfaces on two Aggregation switches in a cross-device Link, and connect the two Aggregation switches through a Peer-Link between them, so that the two Aggregation switches logically resemble a device, and the ports of the two devices together form an Aggregation port, so that all ports participate in data traffic forwarding.

Two devices simultaneously open the IGMP snoring function, and for the devices joining the same multicast group, the problem that some devices cannot receive multicast traffic can exist due to the lack of multicast table item synchronization. When the device wants to receive the multicast traffic, the sending message is sent to only one switch due to the reason of link aggregation, the switch generates a multicast MAC table entry locally, if the multicast group ip traffic added by the device is forwarded to the other switch, and the other switch does not have the multicast table entry, so that the multicast traffic is treated as broadcast, flooded in vlan, and bandwidth resources are wasted.

Disclosure of Invention

One or more embodiments of the present disclosure provide a method and apparatus for synchronizing multicast table entries based on an MLAG environment, which are used to solve the following technical problems: the multicast entries cannot be synchronized, which results in problems of some devices not receiving traffic and wasting broadband resources.

One or more embodiments of the present disclosure adopt the following technical solutions:

One or more embodiments of the present specification provide a multicast table entry synchronization method based on an MLAG environment, the method including: when a designated device accesses a multicast group, an MLAG device receives an IGMP report message sent by the designated device; after receiving the IGMP report message, the MLAG device sets the table entry state of the MLAG device from an initial state to a first state, generates a multicast MAC table entry according to the IGMP report message, and in the initial state, any device is not connected to a designated port where the MLAG device receives the IGMP report message; and in the first state, sending the specific information of the IGMP report message to opposite terminal equipment through a Peer-link so that the opposite terminal equipment sets an entry state from the initial state to a second state after receiving the specific information, and in the second state, generating a multicast MAC entry by the opposite terminal equipment according to the specific information of the IGMP report message, thereby realizing synchronous multicast MAC entries in the MLAG equipment and the opposite terminal equipment and ensuring that the appointed equipment normally receives the multicast group flow.

Further, the sending the specific information of the IGMP report message to the Peer device through the Peer-link specifically includes: after receiving the IGMP report message, the MLAG device screens out specific information in the IGMP report message to generate an MLAG message, wherein the specific information is used for generating the multicast MAC table item; and the MLAG device sends the MLAG message to the opposite terminal device through the Peer-link.

Further, when the information type of the MLAG message is add information, the filtering specific information in the IGMP report message to generate an MLAG message specifically includes: after the MLAG device determines that the IGMP report message accords with the preset rule of the MLAG device, IGMP add information in the IGMP report message is extracted, and corresponding MLAG message information is generated according to the IGMP add information.

Further, after the designated device normally receives the multicast group traffic, the method further includes: the appointed equipment sends an IGMP report message to any one of the MLAG equipment and the opposite terminal equipment according to the received IGMP query message, wherein the IGMP query message is periodically sent by service equipment in an MLAG networking environment; refreshing a group timer of the first state multicast MAC table item when the MLAG device receives the IGMP report message, so as to ensure that the group timer does not exceed a preset time, wherein the group timer counts time according to the received IGMP report message; when the opposite terminal device receives the IGMP report message, refreshing a group timer of the second state multicast MAC table item, generating an MLAG message according to IGMPupdate information in the IGMP report message, sending the MLAG message to the MLAG device through peerlink, and updating the group timer of the MLAG device so as to ensure that the group timer does not exceed preset time.

Further, after the designated device normally receives the multicast group traffic, the method further includes: if the MLAG device enables the quick leave mechanism, any one of the following conditions exists: the group timer of the multicast MAC table item in the first state of the MLAG device exceeds a preset time, or the MLAG device receives IGMP LEAVE messages sent by the appointed device; the MLAG device deletes the multicast MAC table item in the first state, and the first state is converted into the initial state to generate IGMP del information; generating an MLAG message according to the IGMP del information, transmitting the MLAG message to the opposite terminal equipment through a Peer-link, and deleting the second state multicast MAC table entry by the opposite terminal equipment according to the IGMP del information corresponding to the MLAG message information.

Further, if the MLAG device enables a fast leave mechanism and the group timer of the first state multicast MAC entry does not exceed a preset time, the method further comprises: when the opposite terminal equipment receives IGMP LEAVE messages sent by the appointed equipment, deleting the second state multicast MAC table entry of the opposite terminal equipment according to the IGMP LEAVE messages by the opposite terminal equipment to generate IGMP del information; and generating an MLAG message according to the IGMP del information, and transmitting the MLAG message to the MLAG device through a Peer-link so that the MLAG device deletes the first state multicast MAC table item according to the IGMP del information corresponding to the MLAG message information.

Further, when the MLAG device does not enable the quick leave enabled mechanism, the method further comprises: when the table item group timer in the first state exceeds a preset time, the first state is converted into a third state, wherein the MLAG equipment sends a specific group query message to the appointed equipment in the third state, and the specific group query message is used for checking the member state; after receiving the specific group query message, the appointed device sends an IGMP report message to the MLAG device; if the MLAG device does not receive the IGMP report message, deleting the first state multicast MAC table entry to generate IGMP del information; generating an MLAG message according to the IGMP del information, transmitting the MLAG message to the opposite terminal equipment through a Peer-link, and deleting the second state multicast MAC table entry of the opposite terminal equipment according to the IGMP del information in the MLAG message by the opposite terminal equipment.

Further, before the designated device accesses the multicast group, the method further includes: the MLAG device and the opposite terminal device construct an MLAG environment through a Peer-link, wherein the MLAG device, the opposite terminal device and service device form cross-device link aggregation, the service device is used for sending multicast traffic, and the MLAG device and the opposite terminal device are aggregation switches; when the designated device is one, the connection mode of the designated device, the MLAG device and the opposite terminal device comprises any one of double-return access or single-return access; when the designated device is plural, the connection manner of the designated device with the MLAG device and the peer device includes: any one of dual homing access, single homing access and single dual homing hybrid access.

Further, before the MLAG device receives the IGMP report message sent by the specified device, the method further includes: and starting IGMP snoring functions of the MLAG equipment and the opposite terminal equipment.

One or more embodiments of the present specification provide a multicast table entry synchronization apparatus based on an MLAG environment, including:

at least one processor; and

A memory communicatively coupled to the at least one processor; wherein,

The memory stores instructions executable by the at least one processor to enable the at least one processor to:

When a designated device accesses a multicast group, an MLAG device receives an IGMP report message sent by the designated device;

after receiving the IGMP report message, the MLAG device sets the table entry state of the MLAG device from an initial state to a first state, generates a multicast MAC table entry according to the IGMP report message, and in the initial state, any device is not connected to a designated port where the MLAG device receives the IGMP report message;

And in the first state, sending the specific information of the IGMP report message to opposite terminal equipment through a Peer-link so that the opposite terminal equipment sets an entry state from the initial state to a second state after receiving the specific information, and in the second state, generating a multicast MAC entry by the opposite terminal equipment according to the specific information of the IGMP report message, thereby realizing synchronous multicast MAC entries in the MLAG equipment and the opposite terminal equipment and ensuring that the appointed equipment normally receives the multicast group flow.

One or more embodiments of the present specification provide a non-volatile computer storage medium storing computer-executable instructions configured to:

When a designated device accesses a multicast group, an MLAG device receives an IGMP report message sent by the designated device; after receiving the IGMP report message, the MLAG device sets the table entry state of the MLAG device from an initial state to a first state, generates a multicast MAC table entry according to the IGMP report message, and in the initial state, any device is not connected to a designated port where the MLAG device receives the IGMP report message; and in the first state, sending the specific information of the IGMP report message to opposite terminal equipment through a Peer-link so that the opposite terminal equipment sets an entry state from the initial state to a second state after receiving the specific information, and in the second state, generating a multicast MAC entry by the opposite terminal equipment according to the specific information of the IGMP report message, thereby realizing synchronous multicast MAC entries in the MLAG equipment and the opposite terminal equipment and ensuring that the appointed equipment normally receives the multicast group flow.

The above-mentioned at least one technical scheme that this description embodiment adopted can reach following beneficial effect: according to the state of a state machine for processing messages by different conversion MLAG devices from IGMP report sources, when a designated device joins a multicast group for the first time, specific information of the IGMP report message is sent to opposite terminal devices through a Peer-link in a first state, the state of an opposite terminal device list item is converted from the initial state to a second state, and a multicast MAC list item is generated according to the specific information of the IGMP report message, so that the synchronization of the multicast list item is realized, a MLAG scene supports two-layer multicast without multicast as broadcast processing, and the situation of flow failure can not occur under the condition of complex topology.

Drawings

In order to more clearly illustrate the embodiments of the present description or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described below, it being obvious that the drawings in the following description are only some of the embodiments described in the present description, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art. In the drawings:

Fig. 1 is a schematic view of an MLAG networking environment provided in an embodiment of the present disclosure;

Fig. 2 is a schematic flow chart of a multicast table entry synchronization method based on an MLAG environment according to an embodiment of the present disclosure;

FIG. 3 is a schematic diagram of an IGMP original route management state machine according to an embodiment of the present disclosure;

FIG. 4 is a schematic diagram of a routing management state machine of IGMP in an MLAG environment according to an embodiment of the present disclosure;

Fig. 5 is a schematic diagram of an encapsulation format of an MLAG multicast MAC synchronization packet according to an embodiment of the present disclosure;

fig. 6 is a schematic structural diagram of a multicast table entry synchronization device based on an MLAG environment according to an embodiment of the present disclosure.

Detailed Description

In order to make the technical solutions in the present specification better understood by those skilled in the art, the technical solutions in the embodiments of the present specification will be clearly and completely described below with reference to the drawings in the embodiments of the present specification, and it is obvious that the described embodiments are only some embodiments of the present specification, not all embodiments. All other embodiments, which can be made by one of ordinary skill in the art based on the embodiments herein without making any inventive effort, shall fall within the scope of the present disclosure.

The cross-device link Aggregation (MLAG) technology carries out cross-device link Aggregation on interfaces on two Aggregation switches, thereby improving the device from a single board level to a device level and forming an Active-Active system. A Peer-Link Link is connected between two aggregation switches to make it logically like a device. The ports of the two devices together form an aggregate port, so that all ports participate in data traffic forwarding. Compared with stacking, the devices forming the MLAG still need to be managed separately in management, but the MLAG is relatively simple in configuration, and does not need to be restarted after the configuration is completed, forwarding decisions are local, and under normal conditions, traffic does not need to travel an interconnection path between the devices, so that the bandwidth of the interconnection path is prevented from becoming a bottleneck, and delay is reduced. Compared to conventional networks, MLAGs provide higher bandwidth and higher reliability as network traffic increases. And uses static LAG or LACP to connect other switches or servers to achieve cross-device link aggregation. In addition, the MLAG realizes redundancy backup and provides two-layer redundancy protection of Active-Active. The two devices can be independently upgraded, so that the normal forwarding operation of one device is guaranteed, and the running service is hardly influenced.

As shown in fig. 1, the device SWA and the device SWB establish an MLAG through a Peer-link, where a port 1 of the device SWA and a port 1 of the device SWB respectively form a cross-device link aggregation AGG1 with a port 1 and a port 2 of the device SERVER, a port 1 and a port 2 of the device C respectively form a cross-device link aggregation AGG2 with a port 3 of the SWA and the SWB, and a port 1 of the device D is directly connected with a port 3 of the SWB.

Device SERVER sends multicast traffic that device C and device D both want to receive, and therefore both send IGMP report messages out to join the multicast group. The device SWB opens the IGMP reporting function, and the port 3 of the device SWB receives the IGMP report message of the device D, processes the message, and generates a corresponding multicast MAC entry. The device SWA also opens the IGMP reporting function, but since the port 1 and the port 2 of the device C are in the same aggregation, after the port 1 of the device C sends the IGMP report message, the SWA receives and processes the message to generate a corresponding multicast MAC entry. After the SERVER sends the multicast traffic, the traffic is sent out from the port 2 due to the port aggregation, the traffic can only be sent to the device D after SWB, and the device C joining the same group cannot receive the traffic. That is, in the MLAG single-dual-homing hybrid access networking environment, two devices simultaneously open IGMP snooping functions, and for devices joining the same multicast group, there is a problem that some devices cannot receive multicast traffic due to lack of multicast table synchronization.

When the device SERVER sends multicast traffic and the device C wants to receive the multicast traffic, the device C sends igmp report a message, only sends to the SWA due to the link aggregation, the SWA generates a multicast MAC table locally, at this time, the SERVER sends the multicast ip traffic added by the device C as the destination multicast ip, and forwards the multicast ip traffic from the port 2 of the SERVER to the SWB, and because the SWB does not have the multicast table, the multicast traffic is treated as broadcast, floods in the vlan, and wastes bandwidth resources.

The embodiment of the specification provides a multicast table entry synchronization method and device based on an MLAG environment, aiming at a switch, generating a multicast MAC address can be realized by an IGMP snoring/GMRP mode, and the IGMP snoring-based multicast MAC table entry synchronization method and device provided by the embodiment of the specification uses an IGMPv2 mode by default. In addition, it will be clear to those skilled in the art that when a host joins a multicast group, or when it receives a regular query message sent by an interrogator, the host will send a membership report message, i.e. an IGMP report message.

Embodiments of the present specification are described below with reference to the accompanying drawings.

Fig. 2 is a schematic flow chart of a multicast table entry synchronization method based on an MLAG environment according to an embodiment of the present disclosure, as shown in fig. 2, mainly including the following steps:

In step S201, when the designated device accesses the multicast group, the MLAG device receives the IGMP report message sent by the designated device.

Before the appointed equipment accesses the multicast group, the MLAG equipment and the opposite terminal equipment construct an MLAG environment through a Peer-link, wherein the MLAG equipment, the opposite terminal equipment and the service equipment form cross-equipment link aggregation, the service equipment is used for sending multicast traffic, and the MLAG equipment and the opposite terminal equipment are aggregation switches; when the designated device is one, the connection mode of the designated device, the MLAG device and the opposite terminal device comprises any one of double-return access or single-return access; when the designated device is plural, the connection manner of the designated device with the MLAG device and the counterpart device includes: any one of dual homing access, single homing access and single dual homing hybrid access.

It should be noted that, the MLAG device may be the device SWA in fig. 1, the peer device may be the device SWB in fig. 1, the service device corresponds to the SERVER in fig. 1, and the designated device may be the device C or the device D. The device C is double-homing access, and the device D is single-homing access. The IGMP snooping functions of device SWA and device SWB are turned on.

In step S202, after receiving IGMPreport the MLAG device sets the entry state of the MLAG device from the initial state to the first state, and generates a multicast MAC entry according to the IGMP report message.

In the initial state, any device is not connected to the designated port where the MLAG device receives the IGMP report message. The initial state corresponds to No Members Present states in fig. 4, and the first state corresponds to Mlag Output Members Present states, abbreviated MO states, in fig. 4.

In step S203, in the first state, specific information of the IGMP report packet is sent to the Peer device through the Peer-link.

Specifically, after receiving the IGMP report message, the MLAG device screens specific information in the IGMP report message to generate an MLAG message, where the specific information is used to generate a multicast MAC table entry; and the MLAG device sends the MLAG message to the opposite terminal device through the Peer-link.

When the information type of the MLAG message is add information, the MLAG device extracts the IGMP add information in the IGMP report message after determining that the IGMP report message accords with the preset rule of the MLAG device, and generates corresponding MLAG message information according to the IGMP add information.

In step S204, the peer device sets the entry state from the initial state to the second state after receiving the specific information, and in the second state, the peer device generates the multicast MAC entry according to the specific information of the IGMP report message.

Note that the second state corresponds to the Mlag Input Members Present state in fig. 4, abbreviated as MI state.

Step S205, realize the synchronous multicast MAC table item in MLAG apparatus and opposite terminal apparatus, in order to guarantee the designated apparatus receives the multicast group flow normally.

After the designated device normally receives the multicast group traffic, a maintenance operation needs to be performed on the designated device. Wherein the maintenance operations are as follows:

A service device in an MLAG networking environment periodically transmits an IGMP query message, a designated device transmits an IGMP report message to any one of the MLAG device and a peer device according to the received IGMP query message, and when the IGMP report message is received by the MLAG device, a group timer of a first state multicast MAC table entry of the MLAG device is refreshed, so that the group timer does not exceed preset time, wherein the group timer counts time according to the received IGMP report message; when the receiving IGMP report message is the opposite terminal equipment, refreshing a group timer of the second state multicast MAC table item, generating an MLAG message according to IGMPupdate information in the IGMP report message, and sending the MLAG message to the MLAG equipment through peerlink, and updating the group timer of the MLAG equipment to ensure that the group timer does not exceed the preset time.

After the designated device normally receives the multicast group traffic, a synchronous delete entry operation is also required. Wherein the deletion operation is as follows:

If the MLAG device enables the quick leaving mechanism and the group timer of the multicast MAC table item of the first state of the MLAG device exceeds the preset time; or the MLAG device enables the quick leaving mechanism, and the MLAG device receives IGMP LEAVE messages sent by the appointed device, and the method comprises the following steps: the MLAG device deletes the multicast MAC table item in the first state, and changes the first state into the initial state to generate IGMP del information; generating an MLAG message according to the IGMP del information, transmitting the MLAG message to opposite terminal equipment through a Peer-link, and deleting the multicast MAC table entry in the second state by the opposite terminal equipment according to the IGMP del information corresponding to the MLAG message information.

If the MLAG device starts the quick leaving enabling mechanism and the group timer of the first-state multicast MAC table item does not exceed the preset time, when receiving IGMP LEAVE messages sent by the appointed device, the opposite terminal device deletes the second-state multicast MAC table item of the opposite terminal device according to IGMP LEAVE messages to generate IGMP del information; and generating an MLAG message according to the IGMP del information, and sending the MLAG message to the MLAG device through the Peer-link so that the MLAG device deletes the multicast MAC table item in the first state according to the IGMP del information corresponding to the MLAG message information.

Under the condition that the MLAG equipment does not enable the quick leaving mechanism, when the table item group timer in the first state exceeds the preset time, the first state is converted into a third state, wherein the MLAG equipment sends a specific group inquiry message to the appointed equipment in the third state, and the specific group inquiry message is used for checking the member state; after receiving the query message of the specific group, the appointed equipment sends an IGMP report message to the MLAG equipment; if the MLAG device does not receive the IGMP report message, deleting the multicast MAC table entry in the first state to generate IGMP del information; and generating an MLAG message by the IGMP del information, transmitting the MLAG message to opposite terminal equipment through a Peer-link, and deleting a second state multicast MAC table entry of the opposite terminal equipment by the opposite terminal equipment according to the IGMP del information in the MLAG message. Note that the third state corresponds to the Checking Membership state in fig. 4.

In the second embodiment of the present disclosure, a multicast table entry synchronization method based on an MLAG environment is provided, and in the second embodiment, description is given by referring to fig. 1 and fig. 3-5, and AGG2 of device C is taken as a dual homing access device SWA and a device SWB as an example.

The IGMP snooping functions of device SWA and device SWB are turned on. In the MLAG environment, when the device C wants to join the multicast group, the port 1 or the port 2 sends IGMP report messages to the SWA and the SWB through the AGG2, and the description is given below with the AGG2 of the device C as the dual-homing access device SWA and the device SWB.

First, the entries are synchronized when multicast MAC entries are added. In the MLAG environment of fig. 1, when a device C joins a multicast group for the first time, no other device is located at a port of a switch to which the device C is to join, and an IGMP report message is sent to the outside through AGG2, taking as an example that the device C port 1 sends an IGMP report message to a device SWA through AGG 2. When the port 1 sends a message to the SWA due to the reason of link aggregation, the SWA receives an IGMP report message reported from the kernel, and when the protocol stack of the switch receives the IGMP report message uploaded by the kernel of the switch, the received message is confirmed to be legal and the table entry can be generated, and then IGMP add information is generated.

After receiving the IGMP report message reported from the kernel, the SWA changes its state from No Members Present to Mlag Output Members Present to generate a corresponding multicast MAC address. It should be noted that the states of the original route management state machine of the IGMP protocol processing packet include No Members Present states, members Present states, and Checking Membership states, as shown in fig. 3. In the embodiment of the present disclosure, the original Members Present states of the state machine are divided into Mlag Output Members Present states and Mlag Input Members Present states according to the report message source, as shown in fig. 4, fig. 4 shows a routing management state machine of IGMP in an MLAG environment provided in the embodiment of the present disclosure, and provides a processing manner for the messages by each state. If the previous state is still used, SWA and SWB independently run IGMP protocol state machine, and the original Members Present state is divided into Mlag Output Members Present state and Mlag Input Members Present state, so that the table entry consistency in the MLAG environment is realized.

After the state of the SWA is changed from No Members Present to Mlag Output Members Present, specific information is extracted from the report message, and in the adding step, an MLAG message is generated for encapsulating IGMP add information and sent to the opposite terminal device SWB through a peerlink port. The device SWB decapsulates the MLAG message to obtain IGMP add information, and the state of the device SWB is changed from No Members Present to Mlag Input Members Present to generate a corresponding multicast MAC address. Through the steps, the synchronization of multicast table items is realized in the device SWA and the device SWB, and when the SERVER sends traffic to any device in the device SWA and the device SWB, the device SWA and the device SWB can both realize the purpose of forwarding the traffic to the device C.

If the device C port 2 sends an IGMP report message to the SWB, after receiving the IGMP report message, the SWB changes from No Members Present to Mlag Output Members Present, extracts specific information from the report message, generates an MLAG message for encapsulating IGMP add information in the adding step, and sends the MLAG message to the peer device SWA through the peerlink port. The device SWA decapsulates the MLAG message to obtain IGMP add information, and the state of the device SWA is changed from No Members Present state to Mlag Input Members Present state to generate a corresponding multicast MAC address, so that the same multicast MAC entries in AGG2 of the SWA and the SWB are ensured.

Second, multicast MAC entries need to be maintained. The original state is required to be maintained independently by each switch, but maintenance operation is required to be maintained according to report messages sent by the equipment C, and due to the MLAG cross-equipment aggregation environment, the condition that report messages are only sent to any one of SWA or SWB can occur, so that the original state of the switch which is not received is aged, a deleting process is carried out, and the subsequent flow receiving is influenced.

In the MLAG environment of fig. 1, the table entry of IGMP maintains an IGMP query message sent according to the SERVER period, and after receiving the IGMP query message, device C sends an IGMP report message through AGG 2. When the device C sends an IGMP report message through the port 1, and when the port 1 sends the message to the SWA due to the link aggregation, the SWA receives the IGMP report message reported by the kernel, and refreshes the group timer of the MO (Mlag Output) table entry to ensure that the group timer does not timeout. Since the MI (Mlag Input) entries of the SWB will not receive the report message, the group timer will timeout, but the entries will not be deleted at this time, and the flag will be set to the timeout state.

When the device C sends an IGMP query message from the port 2, the SWB receives the IGMP query message reported by the kernel, refreshes the group timer of the MI table entry, encapsulates Update information and sends the Update information to the SWA through the peerlink port, and the SWA receives the Update information of the MLAG decapsulation to Update the group timer of the MO table entry so as to ensure that the group timer cannot overtime.

On the other hand, when the device C leaves the multicast group, the deletion operation of the entries needs to be synchronized in the device SWA and the device SWB, so that the situation of wasting bandwidth resources is avoided. In the MLAG environment, there are two phases for the member to leave the multicast group, one is for the member running IGMPv2 to send an IGMP leave message to inform the IGMP querier that it has left a certain multicast group. The other is that the IGMP inquirer analyzes the multicast group address from the IGMP leave message after receiving the IGMP leave message, and sends an IGMP specific group inquiry message/an IGMP specific source group inquiry message to the multicast group through a receiving interface.

In this embodiment, if IGMP logging enables the fast leave mechanism, and after the MO entry group timer of SWA times out, the deletion process is directly performed, and meanwhile, the encapsulated IGMP del information is sent to the opposite terminal through the peerlink port, and the opposite terminal device deletes the MI entry after receiving the del information. If IGMP logging enables the fast leave mechanism and the MO entry group timer does not time out, there may be a case where device C sends a leave message to device SWA and device C sends a leave message to device SWB. When SWA receives leave message, it directly goes to delete flow, and packages IGMP del information to send to opposite terminal through peerlink port, after opposite terminal device SWB receives del information, it deletes SWB MI list item. When the SWB receives the leave message, the IGMP del information is packaged and sent to the opposite side SWA through the peerlink port, and the opposite side SWA receives the del information and then goes through a deleting process to delete the MO table of the SWA.

If the fast leave mechanism is not enabled by the IGMP snoring, the MO table entry group timer of the device SWA is overtime and then is converted into Checking Membership, a specific group query message is sent, and the robust value times are repeated. If the device SWA does not receive the IGMP report message sent by the device C, deleting the entry, and meanwhile, encapsulating IGMP del information and sending the IGMP del information to the opposite terminal through the peerlink port, and after receiving the del information, the opposite terminal device deletes the MI entry. When the device C sends a GMP report message, the GMP report message may be sent to the device SWA or may be sent to the device SWB; when sent to device SWB, device SWB encapsulates IGMPdel information that is sent to device SWA, and therefore the IGMP report message sent by device C referred to herein includes the decapsulated result and received by the kernel.

Finally, the device C is a dual homing access, and if the dual homing access is changed to a single homing access, the corresponding synchronization operation is as follows: in the MLAG environment of fig. 1, if the device C sends an IGMP report message to the device SWA through the port 1, the SWB port 2 is down, the SWA changes from dual homing to single homing access, and at this time, the MI entry of the SWB updates the port from AGG2 to peerlink ports, so that the state is unchanged. If the device C sends an IGMP report message to the device SWB through the port 2, the SWA port 2 drops, the SWB changes from dual homing to single homing access, and the MO entry on the AGG2 of the SWA is updated to peerlink ports, so that the state is unchanged.

In connection with the above embodiment and fig. 4 of the specification, it should be noted that the method for processing the message in Mlag Output Members Present states and Mlag Input Members Present states is determined according to whether the IGMP report message is received for the first time and the current switch is in the state. When the device to be added into the multicast group is added for the first time, the sent IGMP report message is sent for the first time, at the moment, the switch is in No Members Present state before receiving, the IGMP report message reported by the kernel is converted into Mlag Output Members Present state after being received, and the message is extracted, packaged and sent to the opposite terminal device. When receiving the IGMP report message in the process of deleting the MAC address, the switch is in Mlag Output Members Present state, and the IGMP report message is received by the switch for the first time, and Mlag Output Members Present state performs the operation of not extracting, packaging and sending the message to the opposite terminal.

Similarly, when the MAC address is added, the switch is in No Members Present states, and generates a corresponding multicast address after receiving the encapsulation packet, that is, in this case, mlag Input Members Present states do not perform operations of information extraction, encapsulation, and sending to the peer. However, in the process of deleting the MAC address, the state of the switch is Mlag Input Members Present, and the received IGMP report message is received for the first time, and the operations of extracting information, packaging and sending the message to the peer device are performed on the message. That is to say, in Mlag Output Members Present and Mlag Input Members Present states, if the IGMP report message is received for the first time, the operations of information extraction, encapsulation and forwarding are performed on the message to the opposite end.

In the third embodiment of the present disclosure, a multicast table entry synchronization method based on an MLAG environment is provided in a single homing access, and in the third embodiment, description is given by referring to fig. 1 and fig. 3-5, and AGG2 of a device C is taken as a dual homing access device SWA and a device SWB as an example.

First, the entries are synchronized when multicast MAC entries are added. In the MLAG environment of fig. 1, port 1 of device D is connected with port 3 of SWB, when device D joins a multicast group for the first time, there is no other device at the port of the switch to which device D is to join, an IGMP report message is sent to SWB, SWB receives an IGMP report reported from the kernel and changes from No Members Present to Mlag Output Members Present, and a corresponding multicast MAC address is generated; when the protocol stack of the switch receives the IGMP report message uploaded by the switch core, the IGMP add information is generated after the received message is confirmed to be legal and the table entry can be generated.

After the state of the SWA is changed from No Members Present to Mlag Output Members Present, specific information is extracted from the report message, and in the adding step, an MLAG message is generated for encapsulating IGMP add information and sent to the opposite terminal device SWA through a peerlink port. The device SWA decapsulates the MLAG message to obtain IGMP add information, and the state of the device SWA is changed from No Members Present to Mlag Input Members Present to generate a corresponding multicast MAC address. Through the steps, the synchronization of multicast table items is realized in the device SWA and the device SWB, and when the SERVER sends traffic to any device in the device SWA and the device SWB, the device SWA and the device SWB can both realize the purpose of forwarding the traffic to the device D.

Second, multicast MAC entries need to be maintained. In the MLAG environment of fig. 1, the IGMP entry maintains an IGMP query message sent according to the SERVER period, and after receiving the IGMP query message, the device D sends an IGMP report message to the SWB. The SWB receives the IGMP report message reported by the kernel, and refreshes the group timer of MO (Mlag Output) list items to ensure that the group timer does not timeout. Since the MI (Mlag Input) entries of the SWB will not receive the report message, the group timer will timeout, but the entries will not be deleted at this time, and the flag will be set to the timeout state.

On the other hand, when the device D opens the multicast group, the deletion operation of the entries needs to be synchronized in the device SWA and the device SWB, so that the situation of wasting bandwidth resources is avoided. If IGMP snoring enables a quick leaving mechanism, and the MO table entry group timer of the SWB is overtime, the deletion process is directly carried out, meanwhile, the encapsulated IGMP del information is sent to the opposite terminal through the peerlink port, and the opposite terminal equipment deletes the MI table entry after receiving the del information.

If IGMP logging enables the fast leave mechanism and the MO entry group timer does not time out, there may be a case where device D sends a leave message to device SWB. And after receiving the leave message, operating with the overtime flow.

If the fast leave mechanism is not enabled by IGMP snoring, the MO table entry group timer of the device SWB is overtime and then is converted into Checking Membership, a specific group query message is sent, and the robust value times are repeated. If the device SWB does not receive the IGMP report message sent by the device C, deleting the entry, and meanwhile, encapsulating IGMP del information and sending the IGMP del information to the opposite terminal through the peerlink port, and after receiving the del information, the opposite terminal device deletes the MI entry.

Finally, the device D is a single-homing access, and if the single-homing access is changed to a dual-homing access, the corresponding synchronization operation is as follows: in the MLAG environment of fig. 1, port 2 of SWB is down, device C can only access through port 1 and SWA port 2 in a single-homing mode, at this time, port 2 of SWB is given to UP, at this time, the single-homing access is changed to a double-homing access, at this time, the MI entry of SWB is updated from peerlink ports to AGG2 ports, and the state is unchanged.

The two access scenarios provided in the second and third embodiments are that the IGMP report packet received by the MLAG device port is encapsulated in the locally generated multicast MAC entry and then sent to the opposite device through the peerlink port, the opposite device parses the relevant processing information from the received MLAG protocol packet, and the parsed information goes through the state machine flow.

In one embodiment of the present disclosure, the encapsulation format of the synchronized multicast message of the MLAG is shown in fig. 5, and includes the following information: mlag version, MESSAGE TYPE, MESSAGE LEN, action, mlag id, vlan id, interface, and Group-address, wherein Mlag version refers to a protocol version number for identifying the version of the M-LAG that the device is running. MESSAGE TYPE refers to a message type, which is used to identify the message as that type, fdb or a multicast MAC sync message. MESSAGE LEN refers to the total length of the message. An Action refers to a type of information including ADD/DEL/UPDATE/LEAVE/CLEAR_ALL/CLEAR_VLAN. Mlag ID is a MLAG member (the identity is the actual MLAG member ID in dual entry, and the value is 0 in single entry) where the identity port is located. Vlan id refers to the Vlan id of an entry. Interface refers to the out Interface of an entry. Group-address refers to the multicast Group IP address.

In one embodiment of the present disclosure, in the synchronization method of multicast MAC entries in the MLAG networking environment, the entries are separately processed in two states, so as to achieve the purpose that multicast traffic in the MLAG environment can be forwarded normally. When multiple single-homed devices access the same multicast group, ref_cnt needs to be added to the multicast MAC generated by the MLAG peer peerlink to determine when to delete the entry. In addition, after the equipment is restarted, the MLAG equipment is reconnected, MI table items of normal equipment are all deleted, MO table items are reserved, and the MO table items are synchronized to the opposite end after the MLAG connection is reestablished.

One or more embodiments of the present disclosure provide a multicast table entry synchronization device based on an MLAG environment, as shown in fig. 6, including: at least one processor; and a memory communicatively coupled to the at least one processor; wherein the memory stores instructions executable by the at least one processor to enable the at least one processor to: when the appointed equipment accesses the multicast group, the MLAG equipment receives an IGMP report message sent by the appointed equipment; after receiving the IGMP report message, the MLAG device sets the entry state of the MLAG device from an initial state to a first state, and generates a multicast MAC entry according to the IGMP report message, wherein in the initial state, any device is not accessed at a designated port of the MLAG device for receiving the IGMP report message; in the first state, specific information of the IGMP report message is sent to the opposite terminal equipment through the Peer-link, so that the opposite terminal equipment sets the table entry state from the initial state to the second state after receiving the specific information, and in the second state, the opposite terminal equipment generates a multicast MAC table entry according to the specific information of the IGMP report message, so that the multicast MAC table entry is synchronized in the MLAG equipment and the opposite terminal equipment, and the appointed equipment is ensured to normally receive multicast group flow.

One or more embodiments of the present specification provide a non-volatile computer storage medium storing computer-executable instructions configured to: when the appointed equipment accesses the multicast group, the MLAG equipment receives an IGMP report message sent by the appointed equipment; after receiving the IGMP report message, the MLAG device sets the entry state of the MLAG device from an initial state to a first state, and generates a multicast MAC entry according to the IGMP report message, wherein in the initial state, any device is not accessed at a designated port of the MLAG device for receiving the IGMP report message; in the first state, specific information of the IGMP report message is sent to the opposite terminal equipment through the Peer-link, so that the opposite terminal equipment sets the table entry state from the initial state to the second state after receiving the specific information, and in the second state, the opposite terminal equipment generates a multicast MAC table entry according to the specific information of the IGMP report message, so that the multicast MAC table entry is synchronized in the MLAG equipment and the opposite terminal equipment, and the appointed equipment is ensured to normally receive multicast group flow.

According to the technical scheme in the embodiment of the specification, the table entries are respectively processed in two states, so that the purpose that the multicast traffic of the MLAG environment can be forwarded normally is achieved, synchronization of the multicast table entries is realized, the MLAG scene supports two-layer multicast, multicast is not treated as broadcast processing, and traffic failure can not occur under the condition of complex topology.

In this specification, each embodiment is described in a progressive manner, and identical and similar parts of each embodiment are all referred to each other, and each embodiment mainly describes differences from other embodiments. In particular, for apparatus, devices, non-volatile computer storage medium embodiments, the description is relatively simple, as it is substantially similar to method embodiments, with reference to the section of the method embodiments being relevant.

The foregoing describes specific embodiments of the present disclosure. Other embodiments are within the scope of the following claims. In some cases, the actions or steps recited in the claims can be performed in a different order than in the embodiments and still achieve desirable results. In addition, the processes depicted in the accompanying figures do not necessarily require the particular order shown, or sequential order, to achieve desirable results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

The foregoing is merely one or more embodiments of the present description and is not intended to limit the present description. Various modifications and alterations to one or more embodiments of this description will be apparent to those skilled in the art. Any modification, equivalent replacement, improvement, or the like, which is within the spirit and principles of one or more embodiments of the present description, is intended to be included within the scope of the claims of the present description.

Claims

1. A multicast table entry synchronization method based on an MLAG environment, the method comprising:

In the first state, specific information of the IGMP report message is sent to opposite terminal equipment through a Peer-link, so that the opposite terminal equipment sets an entry state from the initial state to a second state after receiving the specific information, and in the second state, the opposite terminal equipment generates a multicast MAC entry according to the specific information of the IGMP report message, so that the synchronous multicast MAC entry in the MLAG equipment and the opposite terminal equipment is realized, and the appointed equipment is ensured to normally receive multicast group flow; the sending the specific information of the IGMP report message to the Peer device through the Peer-link specifically includes:

After receiving the IGMP report message, the MLAG device screens out specific information in the IGMP report message to generate an MLAG message, wherein the specific information is used for generating the multicast MAC table item;

the MLAG device sends the MLAG message to the opposite terminal device through the Peer-link;

After the designated device normally receives the multicast group traffic, the method further includes:

The appointed equipment sends an IGMP report message to any one of the MLAG equipment and the opposite terminal equipment according to the received IGMP query message, wherein the IGMP query message is periodically sent by service equipment in an MLAG networking environment;

Refreshing a group timer of the multicast MAC table item in the first state when the MLAG device receives the IGMP report message, so as to ensure that the group timer does not exceed a preset time, wherein the group timer counts time according to the received IGMP report message;

When the opposite terminal equipment receives the IGMP report message, refreshing a group timer of the multicast MAC table item in the second state, generating an MLAG message according to IGMP update information in the IGMP report message, and sending the MLAG message to the MLAG equipment through peerlink, and updating the group timer of the MLAG equipment so as to ensure that the group timer does not exceed preset time; after the designated device normally receives the multicast group traffic, the method further includes:

if the MLAG device enables the quick leave mechanism, any one of the following conditions exists:

The group timer of the multicast MAC table item in the first state of the MLAG device exceeds a preset time, or the MLAG device receives IGMP LEAVE messages sent by the appointed device;

the MLAG device deletes the multicast MAC table item in the first state, and the first state is converted into the initial state to generate IGMP del information;

generating an MLAG message according to the IGMP del information, transmitting the MLAG message to the opposite terminal equipment through a Peer-link, and deleting the multicast MAC table entry in the second state by the opposite terminal equipment according to the IGMP del information corresponding to the MLAG message information.

2. The method for synchronizing multicast table entries based on MLAG environment according to claim 1, wherein when the information type of the MLAG message is add information, the specific information in the IGMP report message is screened out to generate an MLAG message, which specifically comprises:

After the MLAG device determines that the IGMP report message accords with the preset rule of the MLAG device, IGMP add information in the IGMP report message is extracted, and corresponding MLAG message information is generated according to the IGMP add information.

3. The method for synchronizing multicast entries based on an MLAG environment of claim 1, wherein if the MLAG device enables a fast leave mechanism and the group timer for the first state multicast MAC entry does not exceed a preset time, the method further comprises:

When the opposite terminal equipment receives IGMP LEAVE messages sent by the appointed equipment, the opposite terminal equipment deletes the multicast MAC table entry in the second state of the opposite terminal equipment according to the IGMP LEAVE messages to generate IGMP del information;

and generating an MLAG message according to the IGMP del information, and transmitting the MLAG message to the MLAG device through a Peer-link so that the MLAG device deletes the first state multicast MAC table item according to the IGMP del information corresponding to the MLAG message information.

4. The method for synchronizing multicast entries based on an MLAG environment according to claim 1, wherein when the MLAG device does not enable a quick leave mechanism, the method further comprises:

When the table item group timer in the first state exceeds a preset time, the first state is converted into a third state, wherein the MLAG equipment sends a specific group query message to the appointed equipment in the third state, and the specific group query message is used for checking the member state;

after receiving the specific group query message, the appointed device sends an IGMP report message to the MLAG device;

If the MLAG device does not receive the IGMP report message, deleting the state multicast MAC table entry of the first state to generate IGMP del information; generating an MLAG message according to the IGMP del information, sending the MLAG message to the opposite terminal equipment through a Peer-link, and deleting the multicast MAC table entry of the second state of the opposite terminal equipment according to the IGMP del information in the MLAG message by the opposite terminal equipment.

5. The method for synchronizing multicast entries based on an MLAG environment according to claim 1, wherein prior to said designated device accessing a multicast group, the method further comprises:

The MLAG device and the opposite terminal device construct an MLAG environment through a Peer-link, wherein the MLAG device, the opposite terminal device and service device form cross-device link aggregation, the service device is used for sending multicast traffic, and the MLAG device and the opposite terminal device are aggregation switches;

When the designated device is one, the connection mode of the designated device, the MLAG device and the opposite terminal device comprises any one of double-return access or single-return access;

When the designated device is plural, the connection manner of the designated device with the MLAG device and the peer device includes: any one of dual homing access, single homing access and single dual homing hybrid access.

6. The method for synchronizing multicast entries based on an MLAG environment according to claim 5, wherein before said MLAG device receives an IGMP report message sent by said designated device, said method further comprises:

And starting IGMP snoring functions of the MLAG equipment and the opposite terminal equipment.

7. A multicast table entry synchronization device based on an MLAG environment, comprising:

at least one processor; and

A memory communicatively coupled to the at least one processor; wherein,