CN108600069B

CN108600069B - Link switching method and device

Info

Publication number: CN108600069B
Application number: CN201810271135.XA
Authority: CN
Inventors: 黄李伟; 王伟
Original assignee: Hangzhou H3C Technologies Co Ltd
Current assignee: New H3C Information Technologies Co Ltd
Priority date: 2018-03-29
Filing date: 2018-03-29
Publication date: 2020-12-25
Anticipated expiration: 2038-03-29
Also published as: CN108600069A

Abstract

The disclosure relates to a link switching method and device, comprising: after receiving a first notification message aiming at a target virtual machine from a first main designated forwarder DF device, determining a standby designated forwarder DF device as a second main DF device; the first main DF device and the standby DF device are network devices in the same multi-homing networking accessed by a target virtual machine; when receiving a data message forwarded to the destination virtual machine, forwarding the data message through the second main DF device; wherein the first notification message is used to characterize that the first main DF device is offline. According to the link switching method and device provided by the embodiment of the disclosure, the problem that the data message is lost in the time period from the offline of the main DF device to the election of a new main DF device can be avoided.

Description

Link switching method and device

Technical Field

The present disclosure relates to the field of communications technologies, and in particular, to a link switching method and apparatus.

Background

EVPN (Ethernet Virtual Private Network) is a two-layer VPN technology. In order to improve the reliability of the access side, the protocol specifies an EVPN multi-homing access network, thereby improving the reliability of the service data message. In the EVPN multi-home access network, one VM (Virtual Machine) can access different VTEP (VXLAN Tunnel End Point) devices through multiple links at the same time. Multiple links of VM accessing different VTEP devices form an ES (Ethernet Segment). ESI (Ethernet Segment Identifier) can be used to identify an ES.

In order to solve the problem that a loop or multiple copies of BUM (Broadcast, Unknown Unicast, Multicast) traffic do not exist when accessing different VTEP devices corresponding to one VM, a plurality of VTEP devices may select one DF from the VTEP devices satisfying the same ESI value, and the DF may be responsible for forwarding packets from and to the VM.

Disclosure of Invention

In view of this, the present disclosure provides a link switching method and a link switching device, so as to avoid a problem that a data packet is lost during a time period from a main DF device being offline to a new main DF device being elected.

According to an aspect of the present disclosure, there is provided a link switching method applied to a virtual local area network tunnel endpoint VTEP, the method including:

after receiving a first notification message aiming at a target virtual machine from a first main designated forwarder DF device, determining a standby designated forwarder DF device as a second main DF device; the first main DF device and the standby DF device are network devices in the same multi-homing networking accessed by a target virtual machine;

when receiving a data message forwarded to the destination virtual machine, forwarding the data message through the second main DF device;

wherein the first notification message is used to characterize that the first main DF device is offline.

According to another aspect of the present disclosure, there is provided a link switching apparatus applied to a virtual local area network tunnel endpoint VTEP that is extensible, the apparatus including:

the first determining module is used for determining the standby designated forwarder DF device as a second main DF device after receiving a first notification message which is from the first main designated forwarder DF device and aims at a target virtual machine; the first main DF device and the standby DF device are network devices in the same multi-homing networking accessed by a target virtual machine;

the first forwarding module is configured to forward the data packet through the second main DF device when receiving the data packet forwarded to the destination virtual machine;

In this way, after receiving the first notification message from the first main DF device, the VTEP determines the standby DF device as the second main DF device, and forwards the data packet to the destination virtual machine through the second main DF device when receiving the data packet forwarded to the destination virtual machine. According to the link switching method and device of the embodiment of the disclosure, when the data packet cannot be forwarded to the destination virtual machine through the first main DF device, the data packet can be forwarded to the destination virtual machine through the standby DF device (the second main DF device), so as to reduce the loss of the data packet from the offline of the first main DF device to the electing of the second main DF device.

Other features and aspects of the present disclosure will become apparent from the following detailed description of exemplary embodiments, which proceeds with reference to the accompanying drawings.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate exemplary embodiments, features, and aspects of the disclosure and, together with the description, serve to explain the principles of the disclosure.

Fig. 1 shows a schematic diagram of a multihoming network according to an embodiment of the present disclosure;

fig. 2 shows a flow chart of a link switching method according to an embodiment of the present disclosure;

fig. 3 shows a flow chart of a link switching method according to an embodiment of the present disclosure;

fig. 4 illustrates a flow diagram of a method of acquiring a standby DF device according to an embodiment of the present disclosure;

FIG. 5 illustrates a flow chart of an exemplary link switching method according to the present disclosure;

fig. 6 illustrates a flow diagram of a method of acquiring a standby DF device according to an embodiment of the present disclosure;

FIG. 7 illustrates a flow chart of an exemplary link switching method according to the present disclosure;

FIG. 8 illustrates a flow chart of an exemplary link switching method according to the present disclosure;

FIG. 9 shows a flow diagram of an exemplary link switching method according to the present disclosure;

fig. 10 shows a flow chart of a link switching method according to an embodiment of the present disclosure;

fig. 11 shows a block diagram of a link switching apparatus according to an embodiment of the present disclosure;

fig. 12 is a block diagram illustrating a structure of a link switching apparatus according to an embodiment of the present disclosure;

fig. 13 is a block diagram illustrating a hardware configuration of a link switching apparatus according to an exemplary embodiment.

Detailed Description

Various exemplary embodiments, features and aspects of the present disclosure will be described in detail below with reference to the accompanying drawings. In the drawings, like reference numbers can indicate functionally identical or similar elements. While the various aspects of the embodiments are presented in drawings, the drawings are not necessarily drawn to scale unless specifically indicated.

The word "exemplary" is used exclusively herein to mean "serving as an example, embodiment, or illustration. Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments.

Furthermore, in the following detailed description, numerous specific details are set forth in order to provide a better understanding of the present disclosure. It will be understood by those skilled in the art that the present disclosure may be practiced without some of these specific details. In some instances, methods, means, elements and circuits that are well known to those skilled in the art have not been described in detail so as not to obscure the present disclosure.

Fig. 1 shows a schematic diagram of a multihoming network according to an embodiment of the present disclosure. VTEP1, VTEP2, VTEP3 and VTEP4 denote VTEP devices; VM1 and VM2 represent VMs (Virtual machines); LSW1 represents a switch. VM1 has multi-homed access to 3 VTEP devices, VTEP1, VTEP2, and VTEP3, respectively, through a switch LSW1, and creates dynamic access points on top of VTEP1, VTEP2, and VTEP3, configuring the same ethernet segment identification ESI values.

VTEP1(IP address 1.1.1.1) sends ES (Ethernet Segment) routes to peers VTEP2, VTEP3 and VTEP4, the ES routes carrying VNI and ESI values, VTEP2(IP address 2.2.2.2) sends ES routes to peers VTEP1 and VTEP3, the ES routes carrying VNI and ESI values, and VTEP3(IP address 3.3.3.3) sends ES routes to peers VTEP1 and VTEP2, the ES routes carrying VNI and ESI values; the aforementioned VTEP1, VTEP2 and VTEP3 form a list of DF elections, as shown in table 1 below.

TABLE 1

ESI	VTEP IP address
		1	1.1.1.1
1	2.2.2.2
		1	3.3.3.3

A designated forwarder DF device is selected from 3 VTEPs according to election rules, and after a VM1 is on line, a gratuitous ARP message is sent to three VTEPs, but 3 AC ports of a VM1 of the 3 VTEPs are accessed, only 1 AC port is a DF port, and the other 2 AC ports are non-DF ports. Assuming that the aforementioned VTEP1 is an optional DF device, the AC port of VTEP1 is the DF port. When receiving the gratuitous ARP message from VM1, VTEP2 and VTEP3 will directly discard the gratuitous ARP message, and VTEP1 receives the gratuitous ARP and generates a forwarding table entry of VM1 on VTEP. VTEP1 may synchronize the learned forwarding table entry of VM1 to peer device VTEP4, and when VM2 sends a data packet to VM1, VTEP4 may forward the data packet to VM1 through VTEP 1.

However, if data packet interaction cannot be performed between VM1 and VTEP1 due to link failure or the like, VTEP1 may send a route withdrawal indication for VM1 to VTEP devices VTEP2, VTEP3, and VTEP4 at opposite ends, and VTEP4 may withdraw a forwarding table entry synchronized with DF device VTEP1 and VTEP1 in response to the route withdrawal indication. VTEP2 and VTEP3 re-determine the new DF device, the specific procedure being as described above. Likewise, the new DF device synchronizes the forwarding entries of VM1 to VTEP 4. However, during the period when VTEP2 and VTEP3 determine a new DF device again, if VTEP4 receives a data packet forwarded by VM2 to VM1, the data packet is lost because there is no DF device at this time.

In order to solve the above technical problem, the present disclosure provides a link switching method.

Fig. 2 shows a flowchart of a link switching method according to an embodiment of the present disclosure, which may be applied in an extensible virtual local area network tunnel endpoint VTEP. As shown in fig. 2, the method may include:

step 201, after receiving a first notification message from a first main designated forwarder DF device for a destination virtual machine, determining a standby designated forwarder DF device as a second main DF device; the first main DF device and the standby DF device are network devices in the same multi-homing networking accessed by a destination virtual machine, and the first notification message is used for representing that the first main DF device is offline.

The first notification message is a notification message sent to the destination virtual machine to characterize that the first main DF device is offline when a link between the first main DF device and the destination virtual machine fails. For example, the first notification message may be a route withdrawal indication for the destination virtual machine sent by the first main DF device. When a link between the first main DF device and the destination virtual machine fails, the first main DF device cannot receive the data packet of the destination virtual machine, or cannot forward the data packet to the destination virtual machine.

After receiving the first notification message, the VTEP determines that the data packet cannot be forwarded to the destination virtual machine through the first main DF device. The VTEP determines a standby DF device and sets the standby DF device as the second primary DF device.

The standby DF device may be a standby DF device that is elected by a VTEP opposite to the VTEP through an election route, the primary DF device sends the standby DF device to the VTEP, and the VTEP receives the standby DF device and stores the standby DF device locally. Or, the standby DF device may be a standby DF device determined from a plurality of peer VTEPs by the VTEP device using the same election rule as the peer VTEP after receiving DF election routes from the peer VTEPs.

Fig. 3 shows a flow chart of a link switching method according to an embodiment of the present disclosure.

In one possible implementation, referring to fig. 3, the determining the standby designated forwarder DF device as the second primary DF device may include:

step 2011, revoking the first master DF device according to the first notification message; for example, after completing the election, the first main DF device may synchronize a forwarding entry for the destination virtual machine to the VTEP, where the forwarding entry includes an IP address of the first main DF device and an IP/MAC address of the destination virtual machine. When the interaction of the data packet cannot be performed between the destination virtual machine and the first main DF device due to link failure and the like, the first main DF device sends a first notification message to the VTEP at the opposite end, where the first notification message may carry an IP address of the first main DF device. After receiving the first notification message, the VTEP may revoke the IP address of the first main DF device in the forwarding table entry.

Step 2022, acquiring a standby DF device;

after the VTEP receives the first notification message from the first primary DF device, the VTEP may determine the standby DF device from a locally stored election list or from a locally stored standby DF device obtained by querying.

Step 2023, determine the standby DF device to be the second primary DF device.

After determining the standby DF device, the VTEP may update the IP address of the first main DF device in the forwarding table entry for the destination virtual machine on the VTEP to the IP address of the standby DF device, so that the standby DF device may be determined as the second main DF device.

Step 202, when receiving the data packet forwarded to the destination virtual machine, forwarding the data packet through the second main DF device.

When receiving the data packet forwarded to the destination virtual machine, the VTEP may forward the data packet to the destination virtual machine through the second main DF device (standby DF device).

In one example, as described above, after the standby DF device is determined as the second main DF device, the IP address of the first main DF device in the forwarding table entry of the VTEP for the destination virtual machine has been updated to the IP address of the standby DF device (i.e., the IP address of the second main DF device), and the VTEP may forward the data packet to the second main DF device according to the IP address of the second main DF device in the forwarding table entry.

Therefore, when the interaction of the data message cannot be performed between the destination virtual machine and the first main DF device due to a link failure or the like, the original link for forwarding the data message to the destination virtual machine can be switched from the first main DF device to the destination virtual machine to the standby DF device to the destination virtual machine, so that the standby DF device receives the data message and forwards the data message to the destination virtual machine.

Illustratively, referring to fig. 1, VM1 is a destination virtual machine, VM2 is a source virtual machine, VTEP1 is a first primary DF device, and VTEP2 is a standby DF device. When data packet interaction cannot be performed between VM1 and VTEP1 due to a link failure or the like, VTEP1 may send a first notification message (e.g., a route withdrawal indication for VM 1) to peer VTEP devices VTEP2, VTEP3, and VTEP 4. After receiving the first notification message, VTEP4 determines the standby DF device VTEP2 as the second primary DF device, for example, VTEP4 may update the IP address of the first primary DF device (VTEP1) in the forwarding table entry for VM1 on VTEP4 to the IP address of the standby DF device (VTEP 2). Upon receiving the data packet forwarded by VM2 to VM1, VTEP4 may forward the data packet to VM1 through VTEP 2.

In this way, after receiving the first notification message from the first main DF device, the VTEP determines the standby DF device as the second main DF device, and forwards the data packet to the destination virtual machine through the second main DF device when receiving the data packet forwarded to the destination virtual machine. According to the link switching method of the embodiment of the present disclosure, when the data packet cannot be forwarded to the destination virtual machine through the first main DF device, the data packet may be forwarded to the destination virtual machine through the standby DF device (the second main DF device), so as to reduce the loss of the data packet from the offline of the first main DF device to the electing of the second main DF device.

Fig. 4 illustrates a flow diagram of a method of acquiring a standby DF device according to an embodiment of the present disclosure.

In one possible implementation manner, referring to fig. 4, the method for acquiring a standby DF device may include:

step 401, receiving a second notification message sent by the first main DF device; and the second notification message carries identification information of the standby DF device.

The second notification message is a message that is sent by the first primary DF device to the VTEP and notifies the VTEP of the standby DF device elected by the current first primary DF device side, and the second notification message may carry identification information of the standby DF device. For example, the second notification message may be a first ES route, and the identification information of the standby DF device may be an IP address of the standby DF device.

And 402, acquiring the standby DF device according to the second notification message.

The VTEP may retrieve the standby DF device from the second notification message.

Fig. 5 shows a flowchart of an exemplary link switching method according to the present disclosure, where step 502 and step 503 are similar to step 201 and step 202 in the above embodiments, and the present disclosure is not repeated herein.

Step 501, under the condition of receiving a first ES route advertised by a first main DF device, acquiring a standby DF device according to the first ES route.

The plurality of VTEP devices at the opposite end of the VTEP can select two VTEP devices from the plurality of VTEPs according to election rules, and the two VTEP devices are respectively used as a first main DF device and a standby DF device. For example, according to the election rule, a plurality of VTEP devices at opposite ends of a VTEP may simultaneously elect two VTEP devices as a first main DF device and a standby DF device, or may sequentially elect two VTEP devices as a first main DF device and a standby DF device. After the election of the standby DF device is completed, the first primary DF device sends a first ES route to the VTEP device of the opposite end, where the first ES route may carry identification information of the standby DF device, for example, the first ES route may carry an IP address of the standby DF device. After receiving the first ES route sent by the first primary DF device, the VTEP may obtain the standby DF device carried in the first ES route from the first ES route.

Step 502, after receiving a route withdrawal indication for a destination virtual machine from a first main designated forwarder DF device, determining a standby designated forwarder DF device as a second main DF device; the first main DF device and the standby DF device are network devices in the same multi-homing network accessed by a destination virtual machine.

Step 503, when receiving the data packet forwarded to the destination virtual machine, forwarding the data packet through the second main DF device.

Illustratively, and still taking fig. 1 as an example. VM1 has multi-homed access to VTEP1, VTEP2, and VTEP3, and may create dynamic access points on VTEP1, VTEP2, and VTEP3 and configure the same ethernet segment identification ESI values for the access points of VTEP1, VTEP2, and VTEP3 described above. Wherein, the IP address of VTEP1 is: 1.1.1.1, the ESI value of the access point is configured to be 1, and the IP address of VTEP2 is: 2.2.2.2, the ESI value of the access point is configured to be 1, and the IP address of VTEP3 is: 3.3.3.3, the ESI value of the access point is configured to be 1.

VTEP1, VTEP2, and VTEP3 send ES routes to each other, including: VTEP1 sends an ES route to VTEP2 and VTEP3, which may carry vni (vxlan id) value 100 and ESI value 1; VTEP2 sends an ES route to VTEP1 and VTEP3, where the ES route may carry VNI value 100 and ESI value 1; VTEP3 sends an ES route, which may carry VNI value 100, ESI value 1, to VTEP1 and VTEP 2.

VTEP1, VTEP2, and VTEP3 may each generate a DF election list based on the DF election routes described above, with reference to table 1.

VTEP1, VTEP2, VTEP3 may perform elections of the first primary DF device and the standby DF device according to the same election rules, for example: among the VTEP devices having the same VNI and ESI values, the VTEP with the smallest IP address is selected as the first main DF device (VTEP1 is determined as the first main DF device), and the VTEP with the smallest IP address among the VTEPs other than the first main DF devices (VTEP2 and VTEP3) is selected as the standby DF device (VTEP2 is determined as the standby DF device).

After the first primary DF device and the standby DF device complete their elections, the first primary DF device VTEP1 sends a first ES route to the VTEP4, where the first ES route may include identification information of the standby DF device. After VTEP4 receives the first ES route, it may obtain the standby DF device from the first ES route.

When data packets cannot be interacted between VM1 and VTEP1 due to a link failure or the like, VTEP1 may send a route withdrawal indication to VTEP 4. After receiving the route withdrawal indication, VTEP4 determines the standby DF device VTEP2 as the second primary DF device, for example, VTEP4 may modify the IP address of the first primary DF device in the forwarding table from VTEP1(1.1.1.1) to VTEP2(2.2.2.2) of the second primary DF device, so that VTEP4 may forward the data packet to VM1 through VTEP2 when receiving the data packet forwarded from VM2 to VM 1.

Fig. 6 illustrates a flow diagram of a method of acquiring a standby DF device according to an embodiment of the present disclosure.

In one possible implementation manner, referring to fig. 6, the method for acquiring a standby DF device may include:

601, receiving third notification messages sent by a plurality of opposite end VTEPs; wherein, each third notification message carries identification information of a VTEP which sends the third notification message;

the third notification message may be a message that is sent by a peer VTEP participating in DF election and carries identification information of the peer VTEP (VTEP sending the third notification). For example, the third notification message may be a second ES route, and the identification information of the VTEP at the opposite end may be an IP address of the VTEP at the opposite end.

Step 602, determining the standby DF device from a plurality of peer VTEPs according to an election rule and the identification information of the VTEP carrying the third notification message.

After receiving the third notification messages sent by the multiple peer VTEPs, the VTEPs may determine the multiple peer VTEPs participating in DF elections according to the identification information of the VTEPs sending the third notification messages, which is carried in the received multiple third notification messages, and may determine the standby DF device from the multiple peer VTEPs according to the election rule.

In this way, after receiving the first notification message representing the first main DF device, the VTEP may determine the standby DF device from the multiple peer VTEPs according to the election rule, and determine the standby DF device as the second main DF device, so that when receiving the data packet forwarded to the destination virtual machine, the VTEP may forward the data packet through the second main DF device. Fig. 7 shows a flowchart of an exemplary link switching method according to the present disclosure, where step 702 and step 703 are similar to step 201 and step 202 in the above embodiments, and the present disclosure is not repeated herein.

And 701, under the condition of receiving second ES routes sent by a plurality of opposite end VTEPs, determining a first main DF device and a standby DF device from the plurality of opposite end VTEPs according to election rules.

When sending the second ES route, the VTEP's multiple peer end VTEPs may also send the second ES route to the VTEP, and the second ES route may carry the ESI and IP address of the VTEP. Thus, the VTEP may obtain the second ES routes sent by the multiple peer VTEPs, and adopt the same election rule as the peer VTEP to elect the first main DF device and the standby DF device from the multiple peer VTEPs, for example, the VTEP may simultaneously elect two VTEP devices from the multiple peer VTEPs as the first main DF device and the standby DF device according to the election rule, or may sequentially elect two VTEP devices as the first main DF device and the standby DF device.

Step 702, after receiving a route withdrawal indication for a destination virtual machine from a first main designated forwarder DF device, determining a standby designated forwarder DF device as a second main DF device; the first main DF device and the standby DF device are network devices in the same multi-homing network accessed by a destination virtual machine.

And 703, forwarding the data packet through the second main DF device when receiving the data packet forwarded to the destination virtual machine.

VTEP1, VTEP2, and VTEP3 may send a second ES route to the peer VTEP, including: VTEP1 sends the second ES route to VTEP2, VTEP3, and VTEP 4; VTEP2 sends the second ES route to VTEP1VTEP3 and VTEP 4; VTEP3 sends a second ES route to VTEP1, VTEP2, and VTEP4, which may carry VNI value 100 and ESI value 1.

VTEP1, VTEP2, VTEP3, and VTEP4 may each generate a list of DF elections based on the second ES route described above, with reference to table 1. VTEP1, VTEP2, VTEP3 and VTEP4 may perform elections of the first primary DF device and the backup DF device according to the same election rules, for example: among the VTEP devices having the same VNI and ESI values, the VTEP with the smallest IP address is selected as the first main DF device (VTEP1 is determined as the first main DF device), and the VTEP with the smallest IP address among the VTEPs other than the first main DF devices (VTEP2 and VTEP3) is selected as the standby DF device (VTEP2 is determined as the standby DF device). The first primary DF device may synchronize a forwarding entry for VM1, which may include IP address 1.1.1.1 of VTEP1 and IP/MAC address of VM1, to peer VTEP 4. .

When data packets cannot be interacted between VM1 and VTEP1 due to a link failure or the like, VTEP1 may send a route withdrawal indication to VTEP 4. After receiving the route withdrawal indication, VTEP4 determines the standby DF device VTEP2 as the second primary DF device, for example, VTEP4 may modify the IP address 1.1.1.1 of the first primary DF device VTEP1 in the forwarding table entry to the address 2.2.2.2.2 of the second primary DF device VTEP2, so that VTEP4 may forward the data packet to VM1 through VTEP2 when receiving the data packet forwarded from VM2 to VM 1.

Fig. 8 illustrates a flow chart of an exemplary link switching method according to the present disclosure.

Step 801, receiving a second ES route sent by a plurality of opposite end VTEPs;

step 802, determining a first main DF device from a plurality of opposite end VTEPs according to election rules;

the VTEP's peer VTEPs may also synchronize the second ES route to the VTEP when sending the second ES route. After receiving the second ES routes sent by the multiple peer VTEPs, the VTEP may adopt the same election rule as the peer VTEP to elect the first primary DF device.

When receiving the data packet forwarded to the destination virtual machine, the first main DF device may forward the data packet to the destination virtual machine.

Step 803, after receiving the route table item withdrawal indication from the first primary DF device, determining a standby DF device from VTEPs other than the first primary DF device from the multiple peer VTEPs according to the election rule.

And step 804, determining the standby designated forwarder DF device as a second main DF device.

After receiving the route withdrawal indication sent by the first primary DF device, the VTEP may determine a standby DF device from a plurality of peer VTEPs except the first primary DF device by using the above election rule, and determine the standby DF device as the second primary DF device. When receiving the data message forwarded to the destination virtual machine, the VTEP may forward the data message to the destination virtual machine through the second main DF device.

Step 805, when receiving the data packet forwarded to the destination virtual machine, forwarding the data packet through the second main DF device.

VTEP1, VTEP2, VTEP3, and VTEP4 may each generate a list of DF elections based on the second ES route described above, with reference to table 1. VTEP1, VTEP2, and VTEP3 may perform elections of the first primary DF device and the backup DF device according to the same election rules, for example: among the VTEP devices having the same VNI and ESI values, the VTEP with the smallest IP address is selected as the first main DF device (VTEP1 is determined as the first main DF device), and the VTEP with the smallest IP address among the VTEPs other than the first main DF devices (VTEP2 and VTEP3) is selected as the standby DF device (VTEP2 is determined as the standby DF device). The first primary DF device may synchronize a forwarding entry for VM1, which may include IP address 1.1.1.1 of VTEP1 and IP/MAC address of VM1, to peer VTEP 4.

The VTEP4 may perform election of the first primary DF device according to the election rule described above, and determine that VTEP1 is the first primary DF device. When receiving the data packet forwarded to VM1 by VM2, VTEP4 may forward the data packet to VM1 through VTEP1 according to the forwarding table entry.

When data packets cannot be interacted between VM1 and VTEP1 due to a link failure or the like, VTEP1 may send a route withdrawal indication to VTEP 4. After receiving the route withdrawal indication, VTEP4 performs election of the standby DF device among the remaining VTEP devices (VTEP2 and VTEP3) using the same election rule, and determines that VTEP2 is the standby DF device. Determining the standby DF device VTEP2 as the second primary DF device, for example, the VTEP4 may modify the IP address of the first primary DF device VTEP1 in the forwarding table from 1.1.1.1 to 2.2.2.2 of the second primary DF device VTEP2, so that when receiving the data packet forwarded from the VM2 to the VM1, the VTEP4 may forward the data packet to the VM1 through the VTEP 2.

Fig. 9 shows a flowchart of an exemplary link switching method according to the present disclosure, wherein step 901, step 902, and step 904 are similar to step 801, step 802, and step 804 in the above embodiments, and the details of the present disclosure are not repeated herein.

Step 901, receiving a second ES route sent from a plurality of peer VTEPs.

And step 902, determining a first main DF device from a plurality of opposite end VTEPs according to election rules.

Step 903, after receiving the route table item revocation indication from the first main DF device, when receiving the data packet forwarded to the destination virtual machine, determining a standby DF device from VTEPs, other than the first main DF device, in the multiple peer VTEPs according to the election rule.

Step 904, determine the standby designated forwarder DF device to be the second primary DF device.

When sending the second ES route, the VTEP's multiple peer end VTEPs may also send the second ES route to the VTEP, and the second ES route may carry the ESI and IP address of the VTEP. After receiving the second ES routes sent by the multiple peer VTEPs, the VTEP may adopt the same election rule as the peer VTEP to elect the first primary DF device. The VTEP may learn the forwarding table entries for the destination virtual machine that the first primary DF device synchronizes.

After receiving the route withdrawal indication sent by the first primary DF device, the VTEP may withdraw the first primary DF device, for example, may identify that the first primary DF device is unavailable. After the VTEP withdraws the first main DF device, when receiving the data packet forwarded to the destination virtual machine, the VTEP may determine a standby DF device from the VTEPs of the opposite ends except the first main DF device by using the election rule, determine the standby DF device as a second main DF device, and forward the data packet to the destination virtual machine through the second main DF device.

Step 905, forwarding the data packet through the second main DF device.

When data packets cannot be interacted between VM1 and VTEP1 due to a link failure or the like, VTEP1 may send a route withdrawal indication to VTEP 4. After receiving the route withdrawal indication, VTEP4 withdraws the forwarding table entry of VTEP1 (which identifies that VTEP1 is not available). When receiving the data packet forwarded to VM1 by VM2 and when the first primary DF device VTEP1 in the forwarding table entry is unavailable, VTEP4 may adopt the election rule to perform election of the standby DF device among the remaining VTEP devices (VTEP2 and VTEP3), and determine that VTEP2 is the standby DF device. The standby DF device VTEP2 is determined as the second primary DF device, for example, the VTEP4 may modify the IP address of the first primary DF device VTEP1 in the forwarding table from 1.1.1.1 to 2.2.2.2 of the second primary DF device VTEP2, so that the VTEP4 may forward the data packet to the VM1 through the VTEP 2.

Fig. 10 shows a flow chart of a link switching method according to an embodiment of the present disclosure. Step 1001 and step 1002 are similar to step 101 and step 102, and are not described herein again in this disclosure.

In one possible implementation, referring to fig. 10, the method may include:

step 1001, after receiving a first notification message from a first main designated forwarder DF device for a destination virtual machine, determining a standby designated forwarder DF device as a second main DF device; the first main DF device and the standby DF device are network devices in the same multi-homing networking accessed by a target virtual machine;

step 1002, when receiving a data packet forwarded to the destination virtual machine, forwarding the data packet through the second main DF device;

step 1003, receiving a fourth notification message from the first main DF device; wherein the fourth notification message characterizes the first main DF device as online.

The fourth notification message may be a notification message sent to the opposite end VTEP of the first main DF device after the first main DF device is online (after the link between the first main DF device and the destination virtual machine is repaired, the first main DF device is online again). For example, the fourth notification message may carry identification information of online of the first main DF device, so that after receiving the fourth notification message, the VTEP at the opposite end may determine that the first main DF device is online according to the identification information.

Step 1004, revoking the second main DF device according to the fourth notification message, and restoring the first main DF device;

for example, after receiving the fourth notification message sent by the first main DF device, the VTEP may replace the IP address of the second main DF device in the forwarding entry with the IP address of the first main DF device (for example, the fourth notification message may carry the IP address of the first main DF device, and the VTEP may obtain the IP address of the first main DF device from the fourth notification message, or when the VTEP cancels the first main DF device, the VTEP may locally record the IP address of the first main DF device, and after receiving the fourth notification message, the VTEP may locally obtain the IP address of the first main DF device), so as to cancel the second main DF device and recover the first main DF device.

Step 1005, when receiving the data packet forwarded to the destination virtual machine, forwarding the data packet through the first main DF device.

In this way, after the failure of the communication link between the first main DF device and the destination virtual machine is recovered, the VTEP may cancel the second main DF device and recover the first main DF device according to the fourth notification message sent by the first main DF device, and switch back the link from the source virtual machine to the communication link between the destination virtual machines corresponding to the second main DF device to the link corresponding to the first main DF device.

Fig. 11 is a block diagram illustrating a structure of a link switching apparatus according to an embodiment of the disclosure, which may be applied to an extensible virtual local area network tunnel endpoint VTEP, and as shown in fig. 11, the apparatus may include:

a first determining module 1101, configured to determine, after receiving a first notification message for a destination virtual machine from a first main designated forwarder DF device, a standby designated forwarder DF device as a second main DF device; the first main DF device and the standby DF device are network devices in the same multi-homing networking accessed by a target virtual machine;

a first forwarding module 1102, configured to forward, when receiving a data packet forwarded to the destination virtual machine, the data packet through the second main DF device;

In this way, after receiving the first notification message from the first main DF device, the VTEP determines the standby DF device as the second main DF device, and forwards the data packet to the destination virtual machine through the second main DF device when receiving the data packet forwarded to the destination virtual machine. According to the link switching apparatus of the embodiment of the present disclosure, when the data packet cannot be forwarded to the destination virtual machine through the first main DF device, the data packet may be forwarded to the destination virtual machine through the standby DF device (the second main DF device), so as to reduce the loss of the data packet from the offline of the first main DF device to the electing of the second main DF device.

Fig. 12 shows a block diagram of a link switching apparatus according to an embodiment of the present disclosure.

In one possible implementation manner, referring to fig. 12, the first determining module 1101 may include:

an revoking sub-module 11011, which may be configured to revoke the first primary DF device according to the first notification message;

a first acquisition sub-module 11012 that may be used to acquire a standby DF device;

a first determination sub-module 11013 may be used to determine the standby DF device as the second primary DF device.

In one possible implementation manner, referring to fig. 12, the apparatus may further include a first obtaining module 1103, where the first obtaining module 1103 may include:

a first receiving sub-module 11031, configured to receive a second notification message sent by the first primary DF device;

a second obtaining sub-module 11032, configured to obtain a standby DF device according to the second notification message; and the second notification message carries identification information of the standby DF device.

In a possible implementation manner, referring to fig. 12, the apparatus may further include a second obtaining module 1104, where the second obtaining module 1104 may include:

a second receiving submodule 11041, configured to receive third notification messages sent from a plurality of peer VTEPs; wherein, each third notification message carries identification information of a VTEP which sends the third notification message;

the second determining sub-module 11042 may be configured to determine the standby DF device from the multiple peer VTEPs according to an election rule and the identification information of the VTEP carrying the third notification message.

In one possible implementation, referring to fig. 12, the apparatus may further include:

a receiving module 1105, configured to receive a fourth notification message from the first master DF device;

a recovery module 1106, configured to revoke the second main DF device according to the fourth notification message, and recover the first main DF device;

a second forwarding module 1107, configured to forward, when receiving a data packet forwarded to the destination virtual machine, the data packet through the first main DF device;

wherein the fourth notification message characterizes the first main DF device as online.

Fig. 13 is a block diagram illustrating a hardware configuration of a link switching apparatus according to an exemplary embodiment. In practical applications, the device may be implemented by a server. Referring to fig. 13, the apparatus 1400 may include a processor 1401, a machine-readable storage medium 1402 storing machine-executable instructions. The processor 1401 and the machine-readable storage medium 1402 may communicate via a system bus 1403. Also, the processor 1401 performs the link switching method described above by reading machine executable instructions in the machine readable storage medium 1402 that logically correspond to the link switching method.

The machine-readable storage medium 1402 referred to herein may 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: random Access Memory (RAM), volatile Memory, non-volatile Memory, flash Memory, a storage drive (e.g., a hard drive), a solid state drive, any type of storage disk (e.g., an optical disk, dvd, etc.), or similar storage media, or a combination thereof. Having described embodiments of the present disclosure, the foregoing description is intended to be exemplary, not exhaustive, and not limited to the disclosed embodiments. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The terms used herein were chosen in order to best explain the principles of the embodiments, the practical application, or technical improvements to the techniques in the marketplace, or to enable others of ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. A link switching method is applied to an extensible virtual local area network tunnel endpoint (VTEP), and comprises the following steps:

2. The method of claim 1, wherein said determining a standby Designated Forwarder (DF) device as a second primary DF device comprises:

revoking the first main DF device according to the first notification message;

acquiring a standby DF device;

determining the standby DF device as a second primary DF device.

3. The method of any one of claims 1 or 2, wherein the method of obtaining the standby DF device comprises:

receiving a second notification message sent by the first main DF device;

acquiring a standby DF device according to the second notification message; and the second notification message carries identification information of the standby DF device.

4. The method of any one of claims 1 or 2, wherein the method of obtaining the standby DF device comprises:

receiving third notification messages sent by a plurality of opposite-end VTEPs; wherein, each third notification message carries identification information of a VTEP which sends the third notification message;

and determining the standby DF equipment from the plurality of opposite end VTEPs according to election rules and the identification information of the VTEP carrying the third notification message.

5. The method of claim 1, further comprising:

receiving a fourth notification message from the first primary DF device;

revoking the second main DF device according to the fourth notification message, and recovering the first main DF device;

when receiving a data message forwarded to the destination virtual machine, forwarding the data message through the first main DF device;

6. A link switching apparatus applied to an extensible virtual local area network tunnel endpoint, VTEP, the apparatus comprising:

7. The apparatus of claim 6, wherein the first determining module comprises:

a revocation submodule, configured to revoke the first master DF device according to the first notification message;

the first obtaining submodule is used for obtaining the standby DF equipment;

a first determining submodule, configured to determine the standby DF device as a second primary DF device.

8. The apparatus according to any one of claims 6 or 7, wherein the apparatus further comprises a first obtaining module, the first obtaining module comprising:

the first receiving submodule is used for receiving a second notification message sent by the first main DF device;

the second obtaining sub-module is used for obtaining the standby DF device according to the second notification message; and the second notification message carries identification information of the standby DF device.

9. The apparatus according to any one of claims 6 or 7, wherein the apparatus further comprises a second obtaining module, the second obtaining module comprising:

the second receiving submodule is used for receiving third notification messages sent by a plurality of opposite-end VTEPs; wherein, each third notification message carries identification information of a VTEP which sends the third notification message;

and the second determining submodule is used for determining the standby DF device from the plurality of opposite end VTEPs according to election rules and the identification information of the VTEP carrying the third notification message.

10. The apparatus of claim 6, further comprising:

a receiving module, configured to receive a fourth notification message from the first main DF device;

the recovery module is used for revoking the second main DF device according to the fourth notification message and recovering the first main DF device;

a second forwarding module, configured to forward, when receiving a data packet forwarded to the destination virtual machine, the data packet through the first main DF device;