CN107819677B

CN107819677B - Message forwarding method and device

Info

Publication number: CN107819677B
Application number: CN201711012659.9A
Authority: CN
Inventors: 程剑锋; 祁正林; 文闻
Original assignee: Hangzhou H3C Technologies Co Ltd
Current assignee: Hangzhou H3C Technologies Co Ltd
Priority date: 2017-10-26
Filing date: 2017-10-26
Publication date: 2020-03-06
Anticipated expiration: 2037-10-26
Also published as: CN107819677A

Abstract

The application provides a method and a device for forwarding a message, wherein the method is applied to a VTEP in a DRS, the VTEP is connected with other opposite end VTEPs in the DRS through an IPL tunnel, and the method comprises the following steps: detecting a link failure of a user-side port connection; determining an AC interface associated with a user-side port; selecting one IPL tunnel from all connected IPL tunnels; associating the determined AC interface with the IPL tunnel port of the selected IPL tunnel; when receiving a VXLAN data message through a local tunnel portal, carrying out VXLAN decapsulation on the VXLAN data message; searching a forwarding table item matched with the destination address of the Ethernet data message after the VXLAN is unpacked; and if the outlet interface in the searched matched forwarding table entry is the AC interface, carrying out IPL tunnel encapsulation on the Ethernet data message subjected to the decapsulation of the VXLAN, sending the Ethernet data message to an opposite-end VTEP through the IPL tunnel interface, and forwarding the message by the opposite-end VTEP, so that the long-distance communication of DR equipment in the DRS system is realized, and the VXLAN specification and the message forwarding efficiency of the whole system are improved.

Description

Message forwarding method and device

Technical Field

The present application relates to the field of computer communications, and in particular, to a method and an apparatus for forwarding a packet.

Background

EVPN (Ethernet Virtual Private Network) is a two-layer VPN technology, where BGP (Border Gateway Protocol) is used on the control plane to advertise routing information, and VXLAN (Virtual eXtensible local area Network) is used on the data plane to forward user packets. When physical sites (Site) of a tenant are scattered at different positions, the EVPN can provide two-layer interconnection for the same subnet of the same tenant based on the existing service provider or enterprise IP (Internet Protocol) network; and three-layer interconnection is provided for different subnets of the same tenant through the EVPN gateway, and three-layer interconnection with an external network is provided for the subnets.

Fig. 1 shows a Distributed aggregation System such as DRS (Distributed Relay System) in EVPN networking. In the networking shown in fig. 1, VTEP11(VXLAN Tunnel End Point) and VTEP2 form a DRS system. In this DRS system, VTEP11 and VTEP12 may also be referred to as DR devices. The IPP ports (Intra-Portal Port, distributed aggregation internal Port) between VTEP11 and VTEP12 are interconnected by IPL (Intra-Portal Link) links. With DRS systems, the highest possible network performance and network availability can be achieved.

Disclosure of Invention

In view of this, the present application provides a message forwarding method and apparatus, so as to implement remote communication of DR devices in a DRS system, improve VXLAN specification of the entire system, and improve message forwarding efficiency.

Specifically, the method is realized through the following technical scheme:

according to a first aspect of the present application, a method for forwarding a packet is provided, where the method is applied to a virtual local area network tunnel endpoint VTEP that is extensible in a distributed relay system DRS, and the VTEP is connected to other peer VTEPs in the DRS through an IPL tunnel, and the method includes:

detecting a link failure of a user-side port connection;

determining an Access Circuit (AC) interface associated with the user-side port;

selecting one IPL tunnel from all connected distributed aggregation internal link IPL tunnels;

associating the determined AC interface with an IPL tunnel port of the selected IPL tunnel;

when receiving a VXLAN data message of an extensible virtual local area network through a local tunnel portal, carrying out VXLAN decapsulation on the VXLAN data message;

searching a forwarding table item matched with the destination address of the Ethernet data message after the VXLAN is unpacked; and if the outlet interface in the searched matched forwarding table entry is the AC interface, carrying out IPL tunnel encapsulation on the Ethernet data message after the VXLAN de-encapsulation, sending the Ethernet data message to the opposite-end VTEP through the IPL tunnel port associated with the AC interface, and forwarding the message by the opposite-end VTEP.

Optionally, the method further includes:

detecting a failed link recovery;

replacing the IPL tunnel port associated with the AC interface with the user-side port.

Optionally, the determining the access circuit AC interface associated with the user-side port includes:

searching a distributed aggregation interface to which a user side port belongs based on a preset mapping relation between the user side port and the distributed aggregation interface;

determining the AC interface bound by the distributed aggregation interface as the AC interface bound by the user-side port.

Optionally, the exit direction of the IPL tunnel portal does not enable the horizontal segmentation function, and the entry direction enables the horizontal segmentation function;

the ingress and egress directions of the VXLAN tunnel portal enable horizontal split functionality.

Optionally, the selecting one IPL tunnel from all connected distributed aggregation internal link IPL tunnels includes:

sending a fault notification message to VTEPs of other opposite ends of the DRS; the fault notification message is used for notifying a fault user-side port on the VTEP;

receiving fault notification response messages returned by the VTEP of the other opposite terminals; the fault notification response message is used for indicating that a designated port on the VTEP which sends the fault notification response message is normal, and the designated port and the failed user-side port belong to the same distributed aggregation interface;

and selecting the IPL tunnel between the source equipment indicated by the failure notification response message received firstly and the VTEP from all connected IPL tunnels.

According to a second aspect of the present application, a packet forwarding apparatus is provided, where the apparatus is applied to a virtual local area network tunnel endpoint VTEP that is extensible in a distributed relay system DRS, and the VTEP is connected to a peer VTEP in the DRS through an IPL tunnel, and the apparatus includes:

the detection unit is used for detecting the link failure of the user side port connection;

a determining unit, configured to determine an access circuit AC interface associated with the user-side port;

a selecting unit, configured to select an IPL tunnel from all connected distributed aggregation internal link IPL tunnels;

a modification unit, configured to associate the determined AC interface with an IPL tunnel port of the selected IPL tunnel;

the forwarding unit is used for performing VXLAN decapsulation on a VXLAN data message when the VXLAN data message is received through a local tunnel portal; searching a forwarding table item matched with the destination address of the Ethernet data message after the VXLAN is unpacked; and if the outlet interface in the searched matched forwarding table entry is the AC interface, carrying out IPL tunnel encapsulation on the Ethernet data message after the VXLAN de-encapsulation, sending the Ethernet data message to the opposite-end VTEP through the IPL tunnel port associated with the AC interface, and forwarding the message by the opposite-end VTEP.

Optionally, the detecting unit is further configured to detect a failed link recovery;

the modifying unit is further configured to replace the IPL tunnel port associated with the AC interface with the user-side port.

Optionally, the determining unit is specifically configured to search a distributed aggregation interface to which the user-side port belongs based on a preset mapping relationship between the user-side port and the distributed aggregation interface; determining the AC interface bound by the distributed aggregation interface as the AC interface bound by the user-side port.

Optionally, the exit direction of the IPL tunnel portal does not enable the horizontal segmentation function, and the entry direction enables the horizontal segmentation function; the ingress and egress directions of the VXLAN tunnel portal enable horizontal split functionality.

Optionally, the selecting unit is specifically configured to send a fault notification message to VTEPs of other peers of the DRS; the fault notification message is used for notifying a fault user-side port on the VTEP; receiving fault notification response messages returned by the VTEP of the other opposite terminals; the fault notification response message is used for indicating that a designated port on the VTEP which sends the fault notification response message is normal, and the designated port and the failed user-side port belong to the same distributed aggregation interface; and selecting the IPL tunnel between the source equipment indicated by the failure notification response message received firstly and the VTEP from all connected IPL tunnels.

The application provides a message forwarding method, a VTEP in a DRS is connected with an opposite-end VTEP through an IPL tunnel, and the IPL tunnel is used for replacing an IPL link, so that on one hand, the IPL tunnel is used for replacing the IPL link, the distance limit of a region to VTEP equipment in the DRS is greatly reduced, and communication can be realized through the IPL tunnel even if a plurality of VTEPs in the DRS are far away from each other; on the other hand, because the IPL tunnel does not need to occupy a physical port resource independently, the port resource is saved, and the VXLAN specification of the whole machine is expanded.

In addition, when the VTEP in the DRS detects a link fault connected with a user side port, the VTEP can modify an AC interface bound with the user side port from being bound with the user side port to being bound with an IPL tunnel port, so that after the link fault, a forwarding table item does not need to be refreshed, the operation of synchronously forwarding the table item from an opposite end to a local end does not need to be triggered, the flow from a VXLAN tunnel can be forwarded to the opposite end without refreshing and synchronizing the forwarding table item, and the opposite end forwards the flow, thereby greatly reducing the working load of equipment and improving the forwarding efficiency.

Drawings

Fig. 1 is a schematic diagram illustrating a network architecture of EVPN employing DRS in a related art;

fig. 2 is a schematic diagram of a network architecture for EVPN employing DRS according to an exemplary embodiment of the present application;

fig. 3 is a flow chart illustrating a message forwarding according to an exemplary embodiment of the present application;

fig. 4 is a schematic diagram illustrating a packet forwarding according to an exemplary embodiment of the present application;

fig. 5 is a block diagram of a message forwarding apparatus according to an exemplary embodiment of the present application.

Detailed Description

Reference will now be made in detail to the exemplary embodiments, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, like numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the present application, as detailed in the appended claims.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used in this application and the appended claims, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. 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 is to be understood that although the terms first, second, third, etc. may be used herein to describe various information, such information should not be limited to these terms. These terms are only used to distinguish one type of information from another. For example, first information may also be referred to as second information, and similarly, second information may also be referred to as first information, without departing from the scope of the present application. The word "if" as used herein may be interpreted as "at … …" or "when … …" or "in response to a determination", depending on the context.

In the networking shown in fig. 1, VTEP11 and VTEP12 in the DRS system are connected via IPL links. VTEP11 and VTEP12 may send protocol messages to the peer over the IPL link.

When the user-side link between VTEP11 and host 12 is unavailable, VTEP11 may forward packets sent to host 12 over the user-side link to VTEP12 over the IPL link, which is forwarded by VTEP12 to host 12.

When the user-side link between VTEP11 and host 12 is unavailable, VTEP12 is triggered to synchronously forward the table entry to VTEP 11. The MAC address of the forwarding entry remains the MAC address of the host 12 and the outgoing interface of the forwarding entry becomes the IPP port. This allows VTEP11 to forward traffic forwarded to host 12 to VTEP12 through the IPP port and to host 12 by VTEP12 when the user-side link between VTEP11 and host 12 is unavailable.

On one hand, however, when a plurality of VTEP devices in the DRS are far away from each other, the connection manner of the physical link, i.e. the IPL link, is difficult to be applied to interconnection of the far-end devices; on the other hand, a port is required to be arranged on the VTEP device as an IPP port, and under the condition that the port of the original VTEP device is limited, a port resource is wasted, and the specification of VXLAN is limited.

In order to solve the above problems, the present application proposes to connect VTEP devices in a DRS system with IPL tunnels instead of the IPL links described above. On one hand, the IPL tunnel is used for replacing an IPL link, so that the distance limit of a region to VTEP equipment in the DRS is greatly reduced, and communication can be realized through the IPL tunnel even if a plurality of VTEPs in the DRS are far away; on the other hand, because the IPL tunnel does not need to occupy a physical port resource independently, the port resource is saved, and the VXLAN specification of the whole machine is expanded.

The networking architecture employed in the present application may be as shown in fig. 2.

In the networking architecture shown in fig. 2, VTEPs of the DRS system are no longer connected by IPL links, but are connected by IPL tunnels. For example, the VTEP21 and the VTEP22 are connected through an IPL tunnel.

The IPL tunnel, which can be understood as a tunnel having all IPL link functions, can be implemented based on VXLAN tunneling technology.

Generally, IPL links have two main types of functions:

the first category of functions: transmitting protocol messages of VTEP equipment at two ends;

the second type of function: when a user side link from one end VTEP to a host is unavailable, the message sent to the host is forwarded to an opposite end VTEP, and the opposite end VTEP forwards the message.

Likewise, the IPL tunnel should also have both functions, namely:

the first category of functions: the IPL tunnel can transmit protocol messages of VTEP equipment at two ends;

the second type of function: when the user side link from one end VTEP to the host is unavailable, the message sent to the host can be forwarded to the opposite end VTEP through the IPL tunnel, and the opposite end VTEP forwards the message.

However, the following problems occur when the IPL tunnel is used to implement the second kind of functions:

1) there is typically a horizontal split between tunnels due to default settings on VTEP forwarding chip ports. The horizontal segmentation can be understood as that messages received by the VTEP from the tunnel are not sent to other tunnels.

For example, as shown in fig. 2, assume that VTEP21 is to forward a packet from Tunnel 21 to host 22. However, when the user-side link between VTEP21 and host 22 is unavailable, VTEP21 cannot directly forward the packet to host 22. VTEP21 needs to tunnel the packet through IPL to VTEP22, which VTEP22 forwards to host 22. However, due to the limitations of horizontal segmentation, VTEP1 will not forward packets from Tunnel 21 to the IPL Tunnel.

2) For a user-side link between VTEP21 and host 22 to be unavailable, VTEP21 needs to forward packets that should be forwarded directly to host 22, through the IPL tunnel to VTEP22, and by VTEP22 to host 22. Inspired by existing DRS with IPL links, a generally conceivable implementation is as follows:

when VTEP21 detects that the subscriber side link of host 22 connected to VTEP21 is unavailable, VTEP22 is triggered to synchronously forward the table entry to VTEP 21. The MAC address of the forwarding entry is still the MAC address of the host 22, and the outgoing interface of the forwarding entry is changed from the original AC interface directed to the host 22 to the Tunnel 23 interface.

In the method, the output interface of the forwarding table entry needs to be refreshed, and the forwarding table entry needs to be synchronously forwarded, so that the workload of the DRS system is greatly improved, and the message forwarding efficiency is reduced when the user side link is unavailable.

In order to solve the above two problems, the present application provides a unicast packet forwarding method in a networking environment where an IPL tunnel is used to replace an EVPN + DRS of an IPL link, so as to solve the above two problems.

Before introducing the message forwarding method provided in the present application, some concepts mentioned herein will be introduced first.

The distributed aggregation interface described above: generally, in a DRS system, user-side ports on multiple VTEPs connecting the same host may constitute a distributed aggregation interface. For example, as shown in fig. 2, both user-side Port 21 on VTEP21 and user-side Port 25 on VTEP22 are connected to host 21, so Port 21 and Port 25 may constitute a distributed aggregation interface DR 21.

A distributed aggregation interface may be understood as a logical concept. Usually, a VTEP records a mapping relationship between a user-side port and a distributed aggregation interface to which the user-side port belongs.

The AC interface comprises: typically, an AC interface, which may be a logical interface, may be created over the distributed aggregation interface. In general, the outgoing interface of a forwarding entry in a DRS system is typically a logical interface like an AC interface.

The IPL tunnel may be a tunnel having an IPL link function, and may be implemented based on a VXLAN tunneling technique. The IPL tunnel port may be understood as a physical port.

Referring to fig. 3, fig. 3 is a flowchart illustrating a message forwarding process that may be used for a VTEP in a DRS system under an EVPN networking according to an exemplary embodiment of the present application, where the message forwarding process may include steps 301 to 302.

Step 301: detecting a link failure of a user-side port connection;

step 302: determining an access circuit AC interface associated with the user-side port.

In the embodiment of the present application, the link failure of the local user-side port connection may generally include a local user-side port failure, such as a local user-side port being down, and may also include a link failure connected to the local user-side port, and the like, which is not particularly limited herein.

When the VTEP is detecting a link failure for a local user-side port connection, the VTEP may determine the AC interface to which the user-side port is bound.

When implemented, the VTEP may determine, based on the stored mapping relationship between the user-side port and the distributed interface, a distributed aggregation interface to which the user-side port belongs, and then determine an AC interface bound to the distributed aggregation interface as an AC interface bound to the user-side port.

Step 303: one IPL tunnel is selected among all the IPL tunnels that are connected.

In this embodiment, when there are only two VTEPs in the DRS system, the VTEPs may determine the locally unique IPL tunnel port as the tunnel port to be associated.

When there are more than two VTEPs in the DRS system, the VTEP may send a fault notification message to other peer VTEPs in the DRS system, where the fault notification message carries information of a faulty user-side port on the VTEP, such as a port number of the user-side port, a distributed aggregation interface ID described by the port, and the like.

After receiving the fault notification message, the VTEP at the other opposite end in the DRS system may obtain the user-side port information of the fault of the VTEP. Generally, the VTEP of the other peer stores a mapping relationship between the local user-side port and the distributed aggregation interface. The VTEPs of other opposite ends may search, based on the distributed aggregation interface ID to which the failure user port carried in the failure notification message belongs, a local user side port corresponding to the distributed aggregation interface ID carried in the failure notification message in a mapping relationship between the local user side port and the distributed aggregation interface. The other peer VTEP may then check whether the found local user-side port is normal. If so, the other peer VTEP may return a fault notification response message to the VTEP.

In summary, the VTEP of the other peer sends a fault notification response message to the VTEP only when the port on the VTEP of the other peer, which belongs to the same distributed aggregation interface as the fault user-side port, is normal, so that the fault notification response message is used to indicate that the designated port on the VTEP that sends the fault notification response message is normal; the designated port and the failed user-side port belong to the same distributed aggregation interface.

The VTEP may receive fault notification response messages returned by other VTEPs.

The VTEP may select an IPL tunnel between the VTEP indicated by the source address of the first received fault notification response message and the VTEP among all IPL tunnels connected.

Of course, the VTEP may also determine the IPL tunnel portal to be associated in other ways, which are not particularly limited herein.

Step 304: and associating the determined AC interface with the IPL tunnel port of the selected IPL tunnel.

In this embodiment of the present application, after determining the AC interface bound by the user-side port and the IPL tunnel port to be associated. The VTEP may modify the binding of the user-side port with the AC interface to bind the local IPL tunnel port.

It should be noted that, after the AC interface is modified from the bound user-side port to the bound local IPL tunnel port, the configuration information corresponding to the AC interface and related to the user-side port is also modified from the configuration information related to the local IPL tunnel port.

For example, after the AC interface is modified from the bound user-side port to the bound local IPL tunnel port, configuration information such as VLAN id corresponding to the AC interface and related to the user-side port is also modified to configuration information such as encapsulation information corresponding to the local IPL tunnel port.

Step 305: when a VXLAN data message is received through a local tunnel port, carrying out VXLAN decapsulation on the VXLAN data message;

step 306: searching a forwarding table item matched with the destination address of the Ethernet data message after the VXLAN is unpacked; and if the outlet interface in the searched matched forwarding table entry is the AC interface, carrying out IPL tunnel encapsulation on the Ethernet data message after the VXLAN de-encapsulation, sending the Ethernet data message to the opposite-end VTEP through the IPL tunnel port associated with the AC interface, and forwarding the message by the opposite-end VTEP.

In this embodiment of the present application, when a link connected to a local user-side port fails and the VTEP receives a VXLAN datagram through a local tunnel port, VXLAN decapsulation may be performed on the VXLAN datagram.

Then VTEP can search for the forwarding table entry matching the destination address of the ethernet data packet decapsulated by VXLAN. If the out interface in the found matching forwarding table entry is the AC interface, the VTEP may perform IPL tunnel encapsulation on the ethernet data packet and send the ethernet data packet to the VTEP at the opposite end through the IPL tunnel port associated with the local AC interface. The VTEP at the opposite end can decapsulate the IPL tunnel of the message and then forward the decapsulated message of the IPL tunnel.

In addition, in this embodiment of the present application, when the VTEP detects that the failed link is recovered to be normal, the VTEP may modify the AC interface from binding the IPL tunnel port to binding the user-side port.

It should be noted that, after the AC interface is modified from being bound to the IPL tunnel port to being bound to the user side port, the configuration information corresponding to the AC and related to the local IPL tunnel port is also modified to the configuration information related to the user port.

For example, after the AC interface is modified from binding the IPL tunnel port to binding the user-side port, encapsulation information corresponding to the AC interface and related to the IPL tunnel port, such as a VXLAN header, a UDP header, and an IP header, may also be modified to configuration information, such as a VLAN id, related to the user-side port.

When the VTEP detects that the failed link is recovered to be normal, the VTEP receives the VXLAN data packet through the local tunnel portal, and performs VXLAN decapsulation on the VXLAN packet. Then, VTEP can search for a forwarding table entry matching the destination address of the ethernet datagram decapsulated by VXLAN. And if the outlet port in the searched matched forwarding table entry is the AC interface, sending a message after the VXLAN tunnel is unpacked through the user side port associated with the current AC interface.

In addition, in the embodiment of the present application, the exit direction of the IPL tunnel portal does not enable the horizontal splitting function, and the entry direction enables the horizontal splitting function; the ingress and egress directions of the VXLAN tunnel portal enable horizontal split functionality. This arrangement may enable messages received from the VXLAN tunnel to be forwarded through the IPL tunnel while enabling messages received from the IPL tunnel to be forwarded from the VXLAN tunnel.

The application provides a message forwarding mode, a VTEP in a DRS is connected with an opposite-end VTEP through an IPL tunnel, and the IPL tunnel is used for replacing an IPL link, so that on one hand, the IPL tunnel is used for replacing the IPL link, the distance limit of a region to VTEP equipment in the DRS is greatly reduced, and communication can be realized through the IPL tunnel even if a plurality of VTEPs in the DRS are far away from each other; on the other hand, because the IPL tunnel does not need to occupy a physical port resource independently, the port resource is saved, and the VXLAN specification of the whole machine is expanded.

In addition, when the VTEP in the DRS detects a link fault connected with a user side port, the VTEP can modify an AC interface bound with the user side port from binding the user side port to binding an IPL tunnel port, so that after the link fault, an output interface of a forwarding table item does not change, and the operation of synchronously forwarding the table item from an opposite terminal to a local terminal does not need to be triggered.

Referring to fig. 4, fig. 4 is a schematic diagram illustrating a packet forwarding according to an exemplary embodiment of the present application.

In the networking shown in fig. 4, VTEP41 and VTEP42 are no longer connected via an IPL link, but instead an IPL Tunnel, such as IPL Tunnel43, is established between VTEP41 and VTEP 42. The established IPL tunnel may be implemented by VXLAN tunneling.

VTEP41 and VTEP42 will periodically send DRS protocol packets through the established IPL tunnel, and establish DRS through the DRS protocol packets.

The physical Port (e.g. Port47) on host 41 connected to VTEP41 and the physical Port (e.g. Port48) on host 41 connected to VTEP42 are added to the generic aggregation interface AGG 41.

The user-side Port (e.g., Port41) on VTEP41 connecting host 41 and the user-side Port (e.g., Port 45) on VTEP42 connecting host 41 join distributed aggregation interface DR 41. An AC (access circuit) interface is created on the DR41, and is AC 41.

A physical Port (such as Port49) connected with VTEP41 on the host 42 and a physical Port (such as Port410) connected with VTEP42 on the host 42 are added into the AGG 42; the user-side Port (e.g., Port42) on VTEP41 connecting host 42 and the user-side Port (e.g., Port46) on VTEP42 connecting host 42 join distributed aggregation interface DR 42. And, an AC interface is created on the DR42, AC 42.

In addition, VTEP41 may record a mapping record of local user-side ports to distributed aggregation interfaces, as shown in table 1.

User side port	Distributed aggregation interface
		Port41	DR41
Port42	DR42

TABLE 1

VTEP42 may record a mapping record of local user-side ports to distributed aggregation interfaces, as shown in table 2.

User side port	Distributed aggregation interface
		Port45	DR41
Port46	DR42

TABLE 2

Furthermore, the outbound direction of IPL tunnel Port43 does not enable horizontal splitting, and the inbound direction of Port43 enables horizontal splitting. The ingress and egress directions of ports (e.g., Port 411) on a VTEP that are tunneled to other VTEPs at a remote site via VXLAN enable horizontal splitting.

This arrangement may enable VTEP41 to forward packets received from Tunnel 41 to Tunnel43, but not to forward packets received from Tunnel43 to Tunnel 41.

Specifically, when VTEP41 receives a packet from Tunnel 41 from Port411, Port411 may add a horizontal partition identifier of the incoming direction of Port411 to the packet. When VTEP41 forwards a packet to Tunnel43 through Port43, Port43 does not add the outbound horizontal split id of Port43 to the packet. Port43 can check the horizontal split flag on the packet to be forwarded, since Port43 only checks the horizontal split flag in the incoming direction of Port411, Port43 does not discard the packet, but instead forwards the packet.

When VTEP41 receives a packet from Tunnel43 from Port43, Port43 may add a horizontal split flag for the incoming direction of Port43 to the packet. When VTEP41 forwards a packet to Tunnel 41 through Port411, Port411 adds to the packet the outbound horizontal split identification of Port 411. Port411 can check the horizontal split flag on the packet to be forwarded, and since Port411 checks the horizontal split flag in the ingress direction of Port43 and the horizontal split flag in the egress direction of Port411, Port411 will discard the packet and not forward the packet.

Likewise, the IPL tunnel Port44 on VTEP42 also enables horizontal splitting in the ingress direction, but does not enable horizontal splitting in the egress direction. This arrangement prevents VTEP42 from forwarding packets received from Tunnel43 to Tunnel 42, and allows VTEP42 to forward packets from Tunnel 42 to Tunnel 43.

With this horizontal split arrangement, when the user-side link between VTEP41 and host 42 is unavailable, VTEP41 can forward packets from the VXLAN Tunnel to VTEP42 via Tunnel43, along the path indicated by the arrow in fig. 4, and to host 42 via VTEP 42.

In the present embodiment, when VTEP41 detects that the user-side link between VTEP41 and host 42 is unavailable, such as Port42 down on VTEP 41. VTEP41 may determine the AC interface to which the user-side link corresponds.

In particular, VTEP41 may determine the AC interface to which user-side Port42 connected the user-side link is bound.

When implemented, VTEP41 may find the distributed aggregation interface to which the user-side Port42 belongs based on the mapping relationship between the user-side Port and the distributed aggregation interface shown in table 1, and in this example, may find the distributed aggregation interface DR42 to which the Port42 belongs. VTEP41 may then determine that the AC interface created on DR2 (i.e., AC42) is the AC interface to which the user-side Port42 is bound.

Furthermore, VTEP41 may also select an IPL tunnel port to be associated among the connected IPL tunnels.

In an alternative implementation, when there are only two devices in the DRS system, such as VTEP41 and VTEP42, VTEP41 may determine a locally unique IPL tunnel Port, such as Port43, as the IPL tunnel Port to be associated.

In another alternative implementation, when there are multiple VTEPs in the DRS system, three are assumed, which are VTEP41, VTEP42, and VTEP 43. User-side Port412 on VTEP43 (not shown in fig. 4) also incorporates distributed aggregation interface DR 42.

VTEP41 may send fault notification messages to VTEP42 and VTEP 43. The fault notification message carries information of the failed user-side Port42 on VTEP41, such as Port number Port42 of the user-side Port, the distributed aggregation interface DR42 of the Port, and the like.

Upon receiving the failure notification message, VTEP42 may obtain information of the failed user-side Port42 carried in the failure notification message, such as the distributed aggregation interface DR42 to which Port42 belongs. VTEP42 may then look up the local user-side port corresponding to DR42 based on the mapping of user-side ports and distributed interfaces shown in table 2. In this example, Port46 may be found. VTEP42 may detect user-side Port46 and whether the link to which Port46 is connected is normal. If normal, VTEP42 may return a fault notification response message to VTEP 41.

As can be seen from the above, VTEP42 will send a fault notification response message to VTEP41 only when Port46 on VTEP42 belonging to the same distributed aggregation interface DR42 as said faulty user-side Port42 is normal, so that the fault notification response message is used to indicate that the designated Port46 on VTEP42 that sent the fault notification response message is normal; the designated Port46 belongs to the same distributed aggregation interface DR42 as the failed user-side Port 42.

Upon receiving the failure notification message, VTEP43 may detect the user-side Port412 belonging to DR42 locally and whether the link to which Port412 is connected is normal. If normal, VTEP43 may return a fault notification response message to VTEP 41.

VTEP41 may receive a failure notification response message returned by VTEP42 and VTEP 43. Assuming that VTEP41 first receives the failure notification response message sent by VTEP42, VTEP41 may treat tunnel Port43 of the IPL tunnel with VTEP42 as the IPL tunnel Port to be associated.

After determining the AC interface and the IPL tunnel Port to be associated, the VTEP41 may modify the AC42 from the bound user side physical Port42 to the associated local IPL tunnel Port43, and modify configuration information related to the remaining ports 42, such as VLAN identifier (e.g., VLAN identifier 1), to configuration information related to the IPL tunnel Port, such as encapsulation information (VXLAN header, UDP header, IP header, etc.).

If VTEP41 receives a VXLAN datagram from a local tunnel portal when the user-side link between VTEP41 and host 42 is unavailable. VTEP41 may forward the message along the path indicated by the arrow in fig. 4.

Specifically, VTEP41 may decapsulate the VXLAN data packet to obtain an ethernet data packet. Then, the VTEP41 may find a forwarding table entry matching the destination MAC of the ethernet datagram in a VSI (Virtual Switch Instance) to which the ethernet datagram belongs. Assuming that the outgoing interface of the forwarding table entry 3 matched with the ethernet data packet is AC42, the VTEP41 may perform IPL tunnel encapsulation on the packet based on the modified encapsulation information corresponding to the AC42, add a VXLAN header, a UDP header, and an IP header corresponding to the IPL tunnel to the ethernet data packet, forward the packet from the IPL tunnel Port43 associated with the AC42, and send the packet to the VTEP42 through the IPL tunnel.

Table 3 shows forwarding table entries corresponding to the VSI to which the packet belongs, as shown in table 3.

MAC address	Outlet interface
		MAC address of host 42	AC42

TABLE 3

After receiving the message encapsulated by the IPL tunnel, VTEP42 may decapsulate the IPL tunnel to obtain an ethernet data message. VTEP2 may determine the VSI described in the ethernet datagram and then look up a forwarding table entry corresponding to the VSI. VTEP2 may look up the forwarding table entry shown in table 3. During forwarding, VTEP42 may encapsulate the ethernet packet with the VLAN id configured in the AC42 interface corresponding to the AC, and then send the packet with the VLAN id added thereto from the physical Port (e.g., Port46) on the local device associated with the AC42 to the host 42.

It should be noted that, in the DRS, generally, after VTEP41 learns the forwarding table entry shown in table 3, the forwarding table entry may be synchronized to VTEP 42. There is a forwarding entry on VTEP42 as shown in table 3.

In the present embodiment, when VTEP41 detects that a user-side link restoration between VTEP41 and host 42 is available, VTEP41 may modify the AC interface (i.e., AC42) back to bound user-side Port42 by bound IPL tunnel Port43 and modify the IPL tunnel-related configuration information, e.g., encapsulation information, back to VLAN identification-related configuration information associated with user-side Port 42.

Thus, after VTEP41 receives the VXLAN data packet through the local tunnel, VTEP41 may decapsulate the VXLAN data packet to obtain an ethernet data packet. VTEP41 may search for a forwarding entry matching the destination MAC address of the ethernet datagram, if the found forwarding entry is the forwarding entry described in table 3 above. VTEP41 may determine that the outgoing interface for the message is AC 42. VTEP41 may add the VLAN identification associated with the Port42 corresponding to AC42 to the packet and forward the packet from the user-side Port42 corresponding to AC42 to host 42.

This completes the description of the embodiment.

As can be seen from the above examples.

Firstly, each VTEP in the DRS, for example, VTEP41 and VTEP42 at the opposite end, are connected through an IPL tunnel, and the IPL tunnel is used to replace an IPL link, so on one hand, the use of the IPL tunnel to replace the IPL link greatly reduces the distance limit of the region to the VTEP device in the DRS, and realizes that communication can be realized through the IPL tunnel even if a plurality of VTEPs in the DRS are far apart; on the other hand, because the IPL tunnel does not need to occupy a physical port resource independently, the port resource is saved, and the VXLAN specification of the whole machine is expanded.

Second, generally, when the user-side link between VTEP41 and host 42 is unavailable, VTEP41 needs to forward the packet that should be directly forwarded to host 42 to VTEP42 through the IPL tunnel and to host 42 by VTEP 42. Inspired by existing DRS with IPL links, a generally conceivable implementation is as follows:

when VTEP41 detects that the subscriber side link connected to host 42 on VTEP41 is unavailable, VTEP42 is triggered to synchronously forward the table entry to VTEP 41. The MAC address of the forwarding entry is still the MAC address of the host 42, and the outgoing interface of the forwarding entry is changed from the original AC interface AC42 directed to the host 42 to the Tunnel43 interface.

In this way, the output interface of the forwarding table entry needs to be refreshed, and the forwarding table entry needs to be synchronously forwarded, so that the workload of the DRS system is greatly increased, and the efficiency of message forwarding when the user side link is unavailable is reduced.

In the present application, when VTEP41 in DRS detects a link failure connected to a user-side Port, VTEP41 may modify AC interface AC42 bound to the user-side Port from binding to user-side Port42 to binding to IPL tunnel Port43, so that after the link failure, an outgoing interface of a forwarding entry does not change, and an operation of synchronously forwarding an entry from an opposite end to the home end does not need to be triggered.

Referring to fig. 5, fig. 5 is a block diagram of a message forwarding apparatus according to an exemplary embodiment of the present application. The device is applied to a tunnel endpoint VTEP of a scalable virtual local area network in a DRS of a distributed relay system, and the VTEP is connected with an opposite end VTEP in the DRS through an IPL tunnel, and the device comprises:

a detecting unit 501, configured to detect a link failure of a user-side port connection;

a determining unit 502, configured to determine an access circuit AC interface associated with the user-side port;

a selecting unit 503, configured to select an IPL tunnel from all connected distributed aggregation internal link IPL tunnels;

a modifying unit 504, configured to associate the determined AC interface with an IPL tunnel port of the selected IPL tunnel;

a forwarding unit 505, configured to perform VXLAN decapsulation on a VXLAN data packet when the VXLAN data packet is received through a local tunnel portal; searching a forwarding table item matched with the destination address of the Ethernet data message after the VXLAN is unpacked; and if the outlet interface in the searched matched forwarding table entry is the AC interface, carrying out IPL tunnel encapsulation on the Ethernet data message after the VXLAN de-encapsulation, sending the Ethernet data message to the opposite-end VTEP through the IPL tunnel port associated with the AC interface, and forwarding the message by the opposite-end VTEP.

Optionally, the detecting unit 501 is further configured to detect a failed link recovery;

the modifying unit 504 is further configured to replace the IPL tunnel port associated with the AC interface with the user-side port.

Optionally, the determining unit 502 is specifically configured to search a distributed aggregation interface to which the user-side port belongs based on a preset mapping relationship between the user-side port and the distributed aggregation interface; determining the AC interface bound by the distributed aggregation interface as the AC interface bound by the user-side port.

Optionally, the selecting unit 503 is specifically configured to send a fault notification message to VTEPs of other peers of the DRS; the fault notification message is used for notifying a fault user-side port on the VTEP; receiving fault notification response messages returned by the VTEP of the other opposite terminals; the fault notification response message is used for indicating that a designated port on the VTEP which sends the fault notification response message is normal, and the designated port and the failed user-side port belong to the same distributed aggregation interface; and selecting the IPL tunnel between the source equipment indicated by the failure notification response message received firstly and the VTEP from all connected IPL tunnels.

The implementation process of the functions and actions of each unit in the above device is specifically described in the implementation process of the corresponding step in the above method, and is not described herein again.

For the device embodiments, since they substantially correspond to the method embodiments, reference may be made to the partial description of the method embodiments for relevant points. The above-described embodiments of the apparatus are merely illustrative, and the units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the scheme of the application. One of ordinary skill in the art can understand and implement it without inventive effort.

The above description is only exemplary of the present application and should not be taken as limiting the present application, as any modification, equivalent replacement, or improvement made within the spirit and principle of the present application should be included in the scope of protection of the present application.

Claims

1. A message forwarding method is characterized in that the method is applied to a virtual local area network tunnel endpoint VTEP in a DRS in a distributed relay system, the VTEP is connected with other opposite end VTEPs in the DRS through IPL tunnels, and the method comprises the following steps:

detecting a link failure of a user-side port connection;

when receiving a VXLAN data message of an extensible virtual local area network through a local VXLAN tunnel port, carrying out VXLAN decapsulation on the VXLAN data message;

2. The method of claim 1, further comprising:

detecting a failed link recovery;

3. The method of claim 1, wherein the determining the access circuit AC interface associated with the user-side port comprises:

4. The method according to claim 1, wherein the exit direction of the IPL tunnel portal does not enable the horizontal split function, the entry direction enables the horizontal split function;

the ingress and egress directions of the local VXLAN tunnel portal enable horizontal segmentation functionality.

5. The method according to claim 1, wherein said selecting one IPL tunnel among all connected distributed aggregated inner link IPL tunnels comprises:

6. A message forwarding apparatus is characterized in that the apparatus is applied to a virtual local area network tunnel endpoint VTEP in a DRS in a distributed relay system, and the VTEP is connected with a peer VTEP in the DRS through an IPL tunnel, and the apparatus includes:

the forwarding unit is used for performing VXLAN decapsulation on a VXLAN data message when the VXLAN data message of the extensible virtual local area network is received through a local VXLAN tunnel port; searching a forwarding table item matched with the destination address of the Ethernet data message after the VXLAN is unpacked; and if the outlet interface in the searched matched forwarding table entry is the AC interface, carrying out IPL tunnel encapsulation on the Ethernet data message after the VXLAN de-encapsulation, sending the Ethernet data message to the opposite-end VTEP through the IPL tunnel port associated with the AC interface, and forwarding the message by the opposite-end VTEP.

7. The apparatus of claim 6,

the detection unit is further used for detecting the failed link recovery;

8. The apparatus according to claim 6, wherein the determining unit is specifically configured to search for a distributed aggregation interface to which the user-side port belongs, based on a preset mapping relationship between the user-side port and the distributed aggregation interface; determining the AC interface bound by the distributed aggregation interface as the AC interface bound by the user-side port.

9. The apparatus according to claim 6, wherein the exit direction of the IPL tunnel portal does not enable the horizontal split function, the entry direction enables the horizontal split function; the ingress and egress directions of the local VXLAN tunnel portal enable horizontal segmentation functionality.

10. The apparatus according to claim 6, wherein the selecting unit is specifically configured to send a failure notification message to VTEPs, which are other peers of the DRS; the fault notification message is used for notifying a fault user-side port on the VTEP; receiving fault notification response messages returned by the VTEP of the other opposite terminals; the fault notification response message is used for indicating that a designated port on the VTEP which sends the fault notification response message is normal, and the designated port and the failed user-side port belong to the same distributed aggregation interface; and selecting the IPL tunnel between the source equipment indicated by the failure notification response message received firstly and the VTEP from all connected IPL tunnels.