WO2019201209A1

WO2019201209A1 - Message forwarding

Info

Publication number: WO2019201209A1
Application number: PCT/CN2019/082716
Authority: WO
Inventors: 温卫真
Original assignee: 新华三技术有限公司
Priority date: 2018-04-19
Filing date: 2019-04-15
Publication date: 2019-10-24
Also published as: CN108600099A; CN108600099B

Abstract

When a first leaf device and a second leave device belong to the same MLAG, the devices have the same virtual IP address. The first leaf device receiving a first routing revoking message sent by the second leaf device; if a destination IP address comprised in the first routing revoking message is the IP address of a dual-homed host which accesses the first leaf device and the second leaf device and next hop information is a virtual IP address, sending a first routing distribution message, the first routing distribution message comprising the destination IP address as the IP address of the host and the first hop information as the real IP address of the first leaf device so that a third leaf device which does not belong to the MLAG generates a first routing table item, the destination IP address of the first routing table item being the IP address of the host and the next hop information being the real IP address of the first leaf device.

Description

Message forwarding

Background technique

MLAG (Multi-Chassis Link Aggregation Group) is a mechanism for implementing cross-device link aggregation. This mechanism improves the link reliability from the board level to the device level by combining two devices to implement cross-device link aggregation to form a MLAG active-active system.

A MLAG deployment scheme based on the Spine-Leaf (backbone-leaf) network is provided. Host A is dual-homed to Leaf device 1 and Leaf device 2; host B is connected to Leaf device 3; Leaf device 1 and leaf device are provided. 2 and the leaf device 3 can communicate with the Spine device through the VXLAN tunnel. When Host B accesses Host A, the destination VTEP (VXLAN Tunnel End Point) IP (Internet Protocol) address of the packet sent from Host B is the virtual IP shared by Leaf Device 1 and Leaf Device 2. address. The Spine device receives the packet from the host B and distributes the packet to the Leaf device 1 or the Leaf device 2 based on the load sharing mechanism. If the link between the leaf device 1 and the host A is faulty, the leaf device 1 forwards the packet to the leaf device 2, and the leaf device 2 forwards the packet to the host A.

DRAWINGS

In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the drawings used in the description of the embodiments will be briefly described below.

FIG. 1 is a schematic diagram of a MLAG deployment scheme in a Spine-Leaf networking according to an embodiment of the present disclosure.

2A is a schematic diagram of a packet forwarding path before a link failure.

2B is a schematic diagram of a message forwarding path after a link failure.

FIG. 3 is a flowchart of a packet forwarding method according to an embodiment of the present disclosure.

4 is a flow chart showing interaction between devices when a link is faulty according to an embodiment of the present disclosure.

FIG. 5 is a schematic diagram of a packet forwarding path after a link failure according to an embodiment of the present disclosure.

FIG. 6 is a flow chart of interaction between devices when the link shown in the embodiment of the present disclosure returns to normal.

FIG. 7 is a schematic diagram of a hardware structure of a Leaf device according to an embodiment of the present disclosure.

FIG. 8 is a schematic structural diagram of a Leaf device according to an embodiment of the present disclosure.

detailed description

Exemplary embodiments will be described in detail herein, examples of which are illustrated in the accompanying drawings. The following description refers to the same or similar elements in the different figures unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the embodiments of the present disclosure. Instead, they are merely examples of devices and methods consistent with aspects of the disclosed embodiments as detailed in the appended claims.

The terms used in the embodiments of the present disclosure are for the purpose of describing the specific embodiments only, and are not intended to limit the embodiments of the present disclosure. The singular forms "a", "the" and "the" It should also be understood that the term "and/or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items.

It should be understood that although the terms first, second, third, etc. may be used to describe various information in the embodiments of the present disclosure, such information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, the first information may also be referred to as the second information without departing from the scope of the embodiments of the present disclosure. Similarly, the second information may also be referred to as the first information. Depending on the context, the word "if" as used herein may be interpreted as "when" or "when" or "in response to a determination."

FIG. 1 is a schematic diagram of a MLAG deployment scheme in a Spine-Leaf networking according to an embodiment of the present disclosure. The network includes one Spine device 100, three Leaf devices (Leaf device 101, Leaf device 102, Leaf device 103) and two hosts (Host 111 and Host 112). The host 111 is dual-homed to the Leaf device 101 and the Leaf device 102 based on the MLAG mechanism. The Leaf device 101 and the Leaf device 102 are called MLAG members, and have the same virtual IP address (MLAG group address), which is recorded as IP12; and the Leaf device 103 It does not belong to the MLAG to which the Leaf device 101 and the Leaf device 102 belong. Each Leaf device is connected through a VXLAN tunnel.

When the forwarding device 112 accesses the packet of the host 111, the leaf device 103 performs VXLAN encapsulation on the packet, and the destination VTEP IP address of the encapsulated packet is the virtual IP address IP12. The Spine device 100 receives the packet and distributes the packet to the Leaf device 101 or the Leaf device 102 based on the load sharing mechanism. If the message is distributed to the Leaf device 101, the message is forwarded by the Leaf device 101 to the host 111. 2A is a schematic diagram of a path for forwarding a message by the Leaf device 101, where a dotted line indicates a forwarding path.

If the physical link between the leaf device 101 and the host device 111 is faulty, the packet is forwarded to the leaf device 101, and the leaf device 101 forwards the packet to the leaf device 102 through the VXLAN tunnel, and then the leaf device 102 forwards the packet. Forwarded to host 111. Referring to FIG. 2B, it is a schematic diagram of a new packet forwarding path after a link failure. As shown in FIG. 2B, there is a round-trip of the packet forwarding path at the leaf device 101, which results in a low forwarding efficiency of the packet.

FIG. 3 is a flowchart of a packet forwarding method according to an embodiment of the present disclosure. The method describes a packet forwarding process from a first Leaf device side in the MLAG.

Step 301: The first Leaf device receives the first route revocation message sent by the second Leaf device.

The second Leaf device and the first Leaf device belong to the same MLAG and have the same virtual IP address.

Step 302: If the destination IP address included in the first route revocation message is the IP address of the local host, and the next hop information is the virtual IP address, the first leaf device sends a first route advertisement message.

If the destination IP address included in the first route revocation message is the IP address of the local host, the next hop information is a virtual IP address shared by the first leaf device and the second leaf device (referred to as a virtual IP address in the following description). The link between the second Leaf device and the local host is faulty and cannot communicate properly. In the following description, unless otherwise specified, the local host refers to a host that is dual-homed to the first Leaf device and the second Leaf device based on the MLAG mechanism. The first leaf device sends a first route advertisement message, where the destination IP address included in the first route advertisement message is the IP address of the local host, and the next hop information is the real IP address of the first Leaf device (the IP address of the physical device) . The Leaf device 101 and the Leaf device 102 in FIG. 1 have the same virtual IP address IP12 and have their own real IP addresses, which are respectively recorded as IP11 and IP22.

Both the route revocation message and the route advertisement message described in the examples of the present disclosure may be in the format of, for example, a BGP message. Any device in the Spine-Leaf network can carry the updated route in a BGP message and send it to another device that has established a BGP neighbor relationship with the device.

In the embodiment of the present disclosure, the Spine-Leaf network further includes a third Leaf device (for example, the Leaf device 103 in FIG. 1) that does not belong to the first Leaf device and the MLAG to which the second Leaf device belongs. When receiving the first route revocation message sent by the second leaf device, the third leaf device deletes the destination IP address and the next hop information included in the first route revocation message, and deletes the destination IP address of the local record as the IP address of the local host. The next hop information is the routing entry of the virtual IP address. When receiving the first route advertisement message sent by the first leaf device, the third leaf device generates the destination IP address as the IP address of the local host according to the destination IP address and the next hop information included in the first route advertisement message, and the next The hop information is the routing entry of the real IP address of the first Leaf device (recorded as the first routing entry). Therefore, the third Leaf device forwards the packet addressed to the local host based on the first routing entry. Specifically, before the third leaf device forwards the packet, the packet is VXLAN encapsulated, and the destination VTEP IP address of the encapsulated packet is the real IP address of the first Leaf device. The message is then forwarded to the first Leaf device. In this way, the packet forwarding path is bypassed at the second Leaf device when the link between the second leaf device and the local host is faulty. For example, the packet is forwarded from the second Leaf device to the first Leaf device and then forwarded to the local device. Host. It can be seen that the packet forwarding method provided by the embodiment of the present disclosure can improve the packet forwarding efficiency.

In an example, when the first leaf device receives the second route advertisement message sent by the second leaf device, if the destination IP address included in the second route advertisement message is the IP address of the local host, the next hop information is The virtual IP address indicates that the link between the second Leaf device and the local host is normal and can communicate. At this time, the first leaf device sends a second route revocation message, where the destination IP address included in the second route revocation message is the IP address of the local host, and the next hop information is the real IP address of the first Leaf device.

In an example, when the third leaf device receives the second route revocation message sent by the first leaf device, deleting the first routing table of the local record according to the destination IP address and the next hop information included in the second route revocation message. The entry is the IP address of the local host and the next hop information is the routing entry of the real IP address of the first leaf device. When the third leaf device receives the second route advertisement message sent by the second leaf device, the destination IP address is the IP address of the local host, and the destination IP address is generated according to the destination IP address and the next hop information included in the second route advertisement message. The one-hop information is the routing entry of the virtual IP address (recorded as the second routing entry). The third Leaf device forwards the packet addressed to the local host based on the second routing entry. Specifically, the third leaf device performs VXLAN encapsulation on the packet before forwarding the packet, where the destination VTEP IP address of the encapsulated packet is a virtual IP address. Then, the Spine device redistributes the packet to the second Leaf device based on the load balancing mechanism, and the second Leaf device forwards the packet to the local host. That is, after the link between the second leaf device and the local host returns to normal, the packet forwarding path is restored.

In addition, if the destination VTEP IP address of the packet received by the first leaf device is a virtual IP address, the packet is sent to the local host based on the MLAG dual-homing access to the first Leaf device and the second Leaf device. The first leaf device obtains the destination IP address carried in the packet, and the destination IP address is the IP address of the local host. Based on the destination IP address, the ARP (Address Resolution Protocol) table and the MAC (Media Access Control, The media access control (address) table determines the port connected to the local host (also referred to as a distributed aggregation port); and determines the communication state of the first leaf device and the local host based on the state of the distributed aggregation port. For example, if the state of the distributed aggregation interface is UP, the communication state between the first leaf device and the local host is normal; if the state of the distributed aggregation interface is DOWN (the chain between the first leaf device and the local host) If the path is faulty, it is determined that the communication state of the first Leaf device and the local host is abnormal.

If the communication status of the first leaf device and the local host is abnormal, the first leaf device sends a third route revocation message, where the destination IP address included in the third route revocation message is the IP address of the local host, and the next hop information is Virtual IP address. When the third route device receives the third route revocation message, the second routing entry of the local record is deleted according to the destination IP address and the next hop information included in the third route revocation message, that is, the destination IP address is the local host. The IP address and the next hop information are the routing entries of the virtual IP address. When the second leaf device receives the third route revocation message, the communication state of the first leaf device and the local host may be abnormal. Therefore, the second leaf device sends a third route advertisement message, where the destination IP address included in the third route advertisement message is the IP address of the local host, and the next hop information is the real IP address of the second leaf device. When receiving the third route advertisement message, the third leaf device generates the destination IP address as the local host's IP address and the next hop information as the second, according to the destination IP address and the next hop information included in the third route advertisement message. The routing entry of the real IP address of the leaf device (recorded as the third routing table entry). Therefore, the third Leaf device forwards the packet addressed to the local host based on the third routing entry. Specifically, the third leaf device performs VXLAN encapsulation on the packet before forwarding the packet, where the destination VTEP IP address of the encapsulated packet is the real IP address of the second Leaf device. The message is then forwarded to the second Leaf device. Therefore, the packet forwarding path is bypassed at the first leaf device when the communication between the first leaf device and the local host is abnormal. For example, the packet is forwarded from the first leaf device to the second leaf device and then forwarded to the local host. It can be seen that the packet forwarding method provided by the embodiment of the present disclosure can improve packet forwarding efficiency.

If the communication status of the first leaf device and the local host is normal, the first leaf device sends a fourth route advertisement message, where the destination IP address included in the fourth route advertisement message is the IP address of the local host, and the next hop information is virtual. IP address. When receiving the fourth route advertisement message, the second leaf device may be configured to detect that the communication state of the first leaf device and the local host is normal, and send a fourth route revocation message, where the destination IP address included in the fourth route revocation message is IP address of the local host. The next hop information is the real IP address of the second Leaf device. When receiving the fourth route revocation message, the third leaf device deletes the third routing entry of the local record according to the destination IP address and the next hop information included in the fourth route revocation message, that is, the destination IP address is the local host. The IP address and the next hop information are the routing entries of the real IP address of the second Leaf device. When the third leaf device receives the fourth route advertisement message, the second routing entry is generated according to the destination IP address and the next hop information included in the fourth route advertisement message, that is, the destination IP address is the IP address of the local host. The next hop information is the routing entry of the virtual IP address. The third Leaf device forwards the packet addressed to the local host based on the second routing entry. Specifically, the third leaf device performs VXLAN encapsulation on the packet before forwarding the packet, where the destination VTEP IP address of the encapsulated packet is a virtual IP address. The Spine device redistributes the packet to the first leaf device based on the load balancing mechanism, and the first leaf device forwards the packet to the local host. In other words, after the communication between the first Leaf device and the local host returns to normal, the forwarding path of the packet is restored accordingly.

The packet forwarding method provided by the embodiment of the present disclosure only performs routing update for the host that is currently interacting with data, and the routes of other hosts that do not exchange data under the faulty distributed aggregation interface are not updated, thereby greatly reducing the number of routing updates. When the faulty distributed aggregation interface is restored to normal, the route of the host that is interacting with the data is also updated. Therefore, the route flapping caused by the large-scale routing update can be avoided.

The Spine-Leaf networking shown in Figure 1 is used as an example to describe the packet forwarding process in detail.

For example, the host 112 accesses the host 111. Referring to FIG. 4, it is a flow chart of interaction between devices when the link is faulty.

In step 401, the leaf device 103 forwards the packet sent by the host 112 to the host 111 based on the routing entry R1 (the destination IP address is the IP address of the host 111 and the next hop information is the virtual IP address), and performs VXLAN encapsulation and encapsulation of the packet. The destination VTEP IP address of the packet is IP12 (virtual IP address).

In step 402, the leaf device 103 sends the encapsulated packet to the Spine device 100 through the outbound interface connected to the Spine device 100.

Step 403: After receiving the packet whose destination VTEP IP is IP12, the Spine device 100 distributes the packet to the leaf device 101 based on the load balancing mechanism.

Step 404: After receiving the packet whose destination VTEP IP is IP12, the leaf device 101 obtains the IP address of the host 111 carried by the packet, and determines the distributed aggregation interface connected to the host 111. If the distributed aggregation interface is normal (in the UP state) The status of the packet is sent to the host 111 through the distributed aggregation interface. The forwarding path is as shown by the dotted line in FIG. 2A. If the distributed aggregation interface is faulty (down state), go to step 405.

In step 405, the leaf device 101 sends a route revocation message to the Spine device 100 (the route reflector). The destination IP address included in the route revocation message is the IP address of the host 111, and the next hop information is a virtual IP address.

In step 406, the Spine device 100 reflects the route revocation message to the Leaf device 102 and the Leaf device 103, respectively.

Step 407: After receiving the route revocation message, the leaf device 103 deletes the locally recorded routing entry R1 according to the destination IP address and the next hop information included in the route revocation message.

Step 408: After receiving the route revocation message, the leaf device 102 sends a route advertisement message to the Spine device 100. The destination IP address included in the route advertisement message is the IP address of the host, and the next hop information is the real IP address of the Leaf device 102. (IP22).

In step 409, the Spine device 100 reflects the route advertisement message to the Leaf device 103.

Step 410: After receiving the route advertisement message, the leaf device 103 generates a routing entry R2 according to the destination IP address and the next hop information included in the route advertisement message. The destination IP address is the IP address of the host 111, and the next hop information. Is the real IP address of the Leaf device 102).

In step 411, the leaf device 103 forwards the packet sent by the host 112 to the host 111 based on the routing entry R2, and performs VXLAN encapsulation on the packet. The destination VTEP IP address of the encapsulated packet is IP22 (the real IP address of the Leaf device 102).

In step 412, the leaf device 103 sends the encapsulated packet to the Spine device 100 through the outbound interface connected to the Spine device 100.

Step 413: After receiving the packet whose destination VTEP IP is IP22, the Spine device 100 forwards the packet directly to the Leaf device 102.

In step 414, the leaf device 102 sends the packet to the host 111 through the distributed aggregation interface connected to the host 111 on the device. The forwarding path is as shown by the dotted line in FIG.

Referring to FIG. 6, a flow chart of interaction between devices when the link is restored to normal.

Step 601: If the distributed aggregation interface of the leaf device 101 and the host 111 is restored to the UP state, the leaf device 101 sends a route advertisement message to the Spine device 100, where the destination IP address included in the route advertisement message is the IP address of the host 111. The next hop information is a virtual IP address (IP12).

In step 602, the Spine device 100 reflects the route advertisement message to the Leaf device 102 and the Leaf device 103.

Step 603: After receiving the route advertisement message, the leaf device 103 generates a routing entry R1 according to the destination IP address and the next hop information included in the route advertisement message. The destination IP address is the IP address of the host 111, and the next hop information. Is a virtual IP address).

Step 604: After receiving the route advertisement message, the leaf device 102 sends a route revocation message to the Spine device 100. The destination IP address included in the route revocation message is the IP address of the host 111, and the next hop information is the real IP address of the Leaf device 102. Address (IP22).

In step 605, the Spine device 100 reflects the route revocation message to the Leaf device 103.

Step 606, after receiving the route revocation message, the leaf device 103 deletes the locally recorded routing entry R2 according to the destination IP address and the next hop information included in the route revocation message (the destination IP address is the IP address of the host 111, One hop information is the real IP address of the Leaf device 102).

In step 607, the leaf device 103 forwards the packet sent by the host 112 to the host 111 based on the routing entry R1, and performs VXLAN encapsulation on the packet. The destination VTEP IP address of the encapsulated packet is IP12 (virtual IP address).

In step 608, the leaf device 103 sends the encapsulated packet to the Spine device 100 through the outbound interface connected to the Spine device 100.

Step 609: After receiving the packet with the destination VTEP IP being IP12, the Spine device 100 re-distributes the packet sent by the host 112 to the host 111 to the Leaf device 101 based on the load sharing mechanism.

In step 610, the leaf device 101 sends the packet to the host 111 through the distributed aggregation port connected to the host 111 on the device, and the forwarding path is restored to the dotted line in FIG. 2A.

FIG. 7 is a schematic structural diagram of hardware of a Leaf device according to an embodiment of the present disclosure. The Leaf device can include a processor 701, a machine readable storage medium 702 that stores machine executable instructions. Processor 701 and machine readable storage medium 702 can communicate via system bus 703. And, by reading and executing machine executable instructions in the machine readable storage medium 702 corresponding to the message forwarding logic, the processor 701 can perform the message forwarding method described above.

The machine-readable storage medium 702 referred to herein can be any electronic, magnetic, optical, or other physical storage device that can contain or store information such as executable instructions, data, and the like. For example, the machine-readable storage medium may be: RAM (Radom Access Memory), volatile memory, non-volatile memory, flash memory, storage drive (such as a hard drive), solid state drive, any type of storage. A disk (such as a compact disc, dvd, etc.), or a similar storage medium, or a combination thereof.

FIG. 8 is a schematic structural diagram of a Leaf device according to an embodiment of the present disclosure. The Leaf device may include a receiving unit 801 and a transmitting unit 802.

The receiving unit 801 is configured to receive a first route revocation message sent by the second Leaf device.

The sending unit 802 is configured to: if the destination IP address included in the first route revocation message is an IP address of the local host, and the next hop information is the virtual IP address, send a first route advertisement message, where the first The destination IP address included in the route advertisement message is the IP address of the local host, and the next hop information is the real IP address of the leaf device, so that the third leaf device that does not belong to the MLAG generates the first routing entry. The destination IP address of the first routing entry is the IP address of the local host, and the next hop information is the real IP address of the Leaf device.

Optionally, the receiving unit 801 is further configured to receive a second route advertisement message sent by the second leaf device, where the sending unit 802 is further configured to: if the destination IP address included in the second route advertisement message is included The address is the IP address of the local host, and the next hop information is the virtual IP address, the second route revocation message is sent, and the destination IP address included in the second route revocation message is the IP address of the local host. The next hop information is the real IP address of the leaf device, so that the third leaf device deletes the first routing entry.

Optionally, the device further includes: a determining unit, configured to determine a communication state of the Leaf device and the local host. In this case, the sending unit 802 is further configured to: if the communication status of the Leaf device and the local host is abnormal, send a third route revocation message, and the destination IP address included in the third route revocation message The address is the IP address of the local host, and the next hop information is the virtual IP address, so that the third leaf device deletes the second routing entry, and the destination IP address of the second routing entry is the local The IP address of the host, the next hop information is the virtual IP address, and the second leaf device sends a third route advertisement message, where the destination IP address included in the third route advertisement message is the local host The IP address, the next hop information is the real IP address of the second Leaf device.

Optionally, the determining unit is configured to: obtain a destination IP address carried in the packet, where the destination IP address is the local IP address, if the packet with the destination VTEP IP address being the virtual IP address is received The IP address of the host is determined, and the distributed aggregation port connected to the local host is determined based on the destination IP address; and the communication state of the Leaf device and the local host is determined based on the state of the distributed aggregation interface.

Optionally, the sending unit 802 is further configured to: if the communication status of the leaf device and the local host is normal, send a fourth route advertisement message, where the destination IP address included in the fourth route advertisement message is The IP address of the local host, the next hop information is the virtual IP address, so that the third Leaf device generates the second routing entry, and causes the second Leaf device to send a fourth route revocation message. The destination IP address included in the fourth route revocation message is an IP address of the local host, and the next hop information is a real IP address of the second leaf device.

Embodiments of the present disclosure also provide a machine readable storage medium including machine executable instructions, such as machine readable storage medium 702 of FIG. 7, which may be processor 701 in a main control board of a network device Executed to implement the packet forwarding method described above.

The above description is only the preferred embodiment of the present disclosure, and is not intended to limit the disclosure, and any modifications, equivalents, improvements, etc., which are made within the spirit and principles of the present disclosure, should be included in the present disclosure. Within the scope of protection.

Claims

A packet forwarding method is applied to the first leaf device in the inter-device link aggregation group MLAG, where the MLAG further includes a second leaf device, the first leaf device and the second The Leaf device has the same virtual internet protocol IP address, and the method includes:

Receiving a first route revocation message sent by the second Leaf device;

If the destination IP address included in the first route revocation message is the IP address of the first host that is dual-homed to the first leaf device and the second leaf device, the next hop information is the virtual IP address. And sending a first route advertisement message, where the destination IP address included in the first route advertisement message is an IP address of the first host, and the next hop information is a real IP address of the first leaf device, so that The third leaf device that does not belong to the MLAG generates a first routing entry, where the destination IP address of the first routing entry is an IP address of the first host, and the next hop information is the first leaf device. Real IP address.
The method of claim 1 wherein the method further comprises:

Receiving a second route advertisement message sent by the second Leaf device;

And if the destination IP address included in the second route advertisement message is the IP address of the first host, and the next hop information is the virtual IP address, sending a second route revocation message, the second route revocation message The destination IP address is the IP address of the first host, and the next hop information is the real IP address of the first leaf device, so that the third leaf device deletes the first routing entry.
The method of claim 1 wherein the method further comprises:

Determining a communication state of the first Leaf device and the first host;

If the communication status of the first leaf device and the first host is abnormal, sending a third route revocation message, where the destination IP address included in the third route revocation message is the IP address of the first host, One hop information is the virtual IP address,

And causing the third leaf device to delete the second routing entry, where the destination IP address of the second routing entry is an IP address of the first host, and the next hop information is the virtual IP address, and

And causing the second leaf device to send a third route advertisement message, where the destination IP address included in the third route advertisement message is an IP address of the first host, and the next hop information is a real condition of the second leaf device. IP address.
The method of claim 3, wherein the determining the communication status of the first Leaf device and the first host comprises:

Determining, according to the received destination VXLAN tunnel endpoint VTEP IP address, the IP address of the first host that is the destination IP address carried in the packet of the virtual IP address, and determining the distributed aggregation port connected to the first host;

And determining, according to a state of the distributed aggregation port, a communication state of the first Leaf device and the first host.
The method of claim 3, wherein the method further comprises:

If the communication status of the first leaf device and the first host is normal, the fourth route advertisement message is sent, and the destination IP address included in the fourth route advertisement message is the IP address of the first host, One hop information is the virtual IP address,

Causing the third Leaf device to generate the second routing entry, and

And causing the second leaf device to send a fourth route revocation message, where the destination IP address included in the fourth route revocation message is an IP address of the first host, and the next hop information is a real condition of the second leaf device. IP address.
A message forwarding device is applied to a first leaf device in a cross-device link aggregation group MLAG, wherein the MLAG further includes a second leaf device, the first leaf device and the second device The Leaf device has the same virtual internet protocol IP address, and the device includes:

a receiving unit, configured to receive a first route revocation message sent by the second Leaf device;

a sending unit, configured to: if the destination IP address included in the first route revocation message is an IP address of the first host that is dual-homed to the first leaf device and the second leaf device, the next hop information is And sending, by the virtual IP address, a first route advertisement message, where the destination IP address included in the first route advertisement message is an IP address of the first host, and the next hop information is the first leaf device An IP address, in which the third leaf device that does not belong to the MLAG generates a first routing entry, the destination IP address of the first routing entry is an IP address of the first host, and the next hop information is the The real IP address of the first Leaf device.
The device of claim 6 wherein:

The receiving unit is further configured to receive a second route advertisement message sent by the second leaf device;

The sending unit is further configured to: if the destination IP address included in the second route advertisement message is an IP address of the first host, and the next hop information is the virtual IP address, send a second route revocation message The destination IP address included in the second route revocation message is the IP address of the first host, and the next hop information is the real IP address of the first leaf device, so that the third leaf device deletes the The first routing entry is described.
The device of claim 6 wherein said device further comprises:

a determining unit, configured to determine a communication state of the first Leaf device and the first host;

The sending unit is further configured to: if the communication state of the first leaf device and the first host is abnormal, send a third route revocation message, where the destination IP address included in the third route revocation message is the The IP address of the first host, the next hop information is the virtual IP address, so that the third leaf device deletes the second routing entry, and the destination IP address of the second routing entry is the first host The IP address, the next hop information is the virtual IP address, and the second leaf device sends a third route advertisement message, where the destination IP address included in the third route advertisement message is the first host The IP address, the next hop information is the real IP address of the second Leaf device.
The apparatus according to claim 8, wherein said determining unit is specifically configured to

Determining, according to the IP address of the first host that is the destination IP address carried in the packet with the destination VXLAN tunnel end VTEP IP address being the virtual IP address, determining the distributed aggregation port connected to the first host;

And determining, according to a state of the distributed aggregation port, a communication state of the first Leaf device and the first host.
The apparatus according to claim 8, wherein said transmitting unit is further used for

If the communication status of the first leaf device and the first host is normal, the fourth route advertisement message is sent, and the destination IP address included in the fourth route advertisement message is the IP address of the first host, The first hop information is the virtual IP address, so that the third leaf device generates the second routing entry, and the second leaf device sends a fourth route revocation message, where the fourth route revocation message is The destination IP address is the IP address of the first host, and the next hop information is the real IP address of the second Leaf device.
A Leaf device, the processor device comprising a processor and a machine readable storage medium storing machine executable instructions executable by the processor, the processor being Execution of instructions prompts:

Receiving a first route revocation message sent by the second leaf device in the inter-device link aggregation group MLAG, where the MLAG includes the leaf device and the second leaf device, the leaf device and the second leaf The device has the same virtual internet protocol IP address;

If the destination IP address included in the first route revocation message is the IP address of the first host that is dual-homed to the leaf device and the second leaf device, and the next hop information is the virtual IP address, Sending a first route advertisement message, where the destination IP address included in the first route advertisement message is an IP address of the first host, and the next hop information is a real IP address of the leaf device, so that the The third leaf device of the MLAG generates a first routing entry, the destination IP address of the first routing entry is an IP address of the first host, and the next hop information is a real IP address of the Leaf device.
The device of claim 11 wherein said machine executable instructions further cause said processor to:

Receiving a second route advertisement message sent by the second Leaf device;

And if the destination IP address included in the second route advertisement message is the IP address of the first host, and the next hop information is the virtual IP address, sending a second route revocation message, the second route revocation message The destination IP address is the IP address of the first host, and the next hop information is the real IP address of the leaf device, so that the third leaf device deletes the first routing entry.
The device of claim 11 wherein said machine executable instructions further cause said processor to:

Determining a communication status of the Leaf device and the first host;

If the communication status of the leaf device and the first host is abnormal, sending a third route revocation message, where the destination IP address included in the third route revocation message is the IP address of the first host, and the next hop The information is the virtual IP address, so that the third leaf device deletes the second routing entry, the destination IP address of the second routing entry is the IP address of the first host, and the next hop information is The virtual IP address is configured, and the second leaf device sends a third route advertisement message, where the destination IP address included in the third route advertisement message is the IP address of the first host, and the next hop information is the The real IP address of the second Leaf device.
The device of claim 13 wherein said machine executable instructions further cause said processor to: when determining a communication state of said Leaf device with said first host:

Determining, according to the received destination VXLAN tunnel endpoint VTEP IP address, the IP address of the first host that is the destination IP address carried in the packet of the virtual IP address, and determining the distributed aggregation port connected to the first host;

And determining, according to a status of the distributed aggregation port, a communication status between the Leaf device and the first host.
The device of claim 13 wherein said machine executable instructions further cause said processor to:

If the communication status of the leaf device and the first host is normal, the fourth route advertisement message is sent, and the destination IP address included in the fourth route advertisement message is the IP address of the first host, and the next hop The information is the virtual IP address, so that the third Leaf device generates the second routing entry, and causes the second Leaf device to send a fourth route revocation message, where the fourth route revocation message is included. The destination IP address is the IP address of the first host, and the next hop information is the real IP address of the second Leaf device.
A machine-readable storage medium, wherein the machine-readable storage medium stores machine-executable instructions that, when executed by a processor, implement the method of any of claims 1-5 step.