Packet forwarding method and apparatus

Patent metadata

Field	Value
Publication number	US-2024267324-A1
Application number	US-202418598748-A
Country	US
Kind code	A1
Filing date	Mar 7, 2024
Priority date	Oct 29, 2021
Publication date	Aug 8, 2024
Grant date	—

Abstract

A packet forwarding method and apparatus are described that pertain to the field of communication technologies. During selecting, from outbound interfaces of a plurality of forwarding chips, an outbound interface used for packet forwarding, a chassis-shaped device considers both: a role of the outbound interface (whether the outbound interface is an outbound interface of a shortest path or an outbound interface of a non-shortest path), and a congested state of the outbound interface. As such, the chassis-shaped device flexibly selects a forwarding path for a data packet based on a congestion situation of the forwarding path. In this way, an application of an adaptive routing technology is extended to the chassis-shaped device.

First claim

1 . A packet forwarding method performed by a first chassis-shaped device comprising N forwarding chips, where N is greater than or equal to 2, and wherein the method comprises:
receiving a first data packet from a first host; obtaining M outbound interfaces corresponding to the first data packet; selecting a target outbound interface, from the M outbound interfaces, based on both:
a congested state of each of the M outbound interfaces, and
a role of each outbound interface, wherein the role comprises:
an outbound interface of a shortest path between the first chassis-shaped device and a second chassis-shaped device, and
an outbound interface of a non-shortest path between the first chassis-shaped device and the second chassis-shaped device; and

sending, in accordance with the selecting, the first data packet to the second chassis-shaped device through the target outbound interface.

2 . The method according to claim 1 , wherein:
the shortest path is a direct link between the first chassis-shaped device and the second chassis-shaped device, and the non-shortest path is a path connecting the first chassis-shaped device and the second chassis-shaped device through a third chassis-shaped device.

3 . The method according to claim 1 , wherein before the selecting a target outbound interface, the method further comprises:
determining the role of each of the M outbound interfaces based on a destination Internet protocol (IP) address of the first data packet and a first forwarding entry stored in the first chassis-shaped device, wherein the first forwarding entry comprises a correspondence among:
a route prefix,
an equal-cost multi-path (ECMP) group, and
a role of an outbound interface in the ECMP group,
wherein the route prefix comprises a prefix of the destination IP address of the first data packet, and
wherein the ECMP group comprises the M outbound interfaces.

4 . The method according to claim 3 , wherein before the determining the role of each of the M outbound interfaces, the method further comprises:
receiving a plurality of border gateway protocol (BGP) packets from the second chassis-shaped device, wherein each of the plurality of BGP packets comprises the route prefix and an autonomous system (AS) path attribute; and generating the first forwarding entry based on route prefixes and AS path attributes in the plurality of BGP packets.

5 . The method according to claim 4 , wherein the plurality of BGP packets comprise a first BGP packet and a second BGP packet, wherein a quantity of AS numbers in an AS path attribute of the first BGP packet is a specified quantity, wherein a quantity of AS numbers in an AS path attribute of the second BGP packet is greater than the specified quantity, and wherein the generating the first forwarding entry based on the plurality of BGP packets comprises:
obtaining a shortest path route based on the first BGP packet, wherein the shortest path route indicates a correspondence between the route prefix and the outbound interface of the shortest path; obtaining a non-shortest path route based on the second BGP packet, wherein the non-shortest path route indicates a correspondence between the route prefix and the outbound interface of the non-shortest path; and generating the first forwarding entry based on the shortest path route and the non-shortest path route.

6 . The method according to claim 5 , wherein the AS number in the AS path attribute of the first BGP packet is an AS number of the second chassis-shaped device, and wherein the AS number in the AS path attribute of the second BGP packet is an AS number of the second chassis-shaped device and an AS number of the third chassis-shaped device.

7 . The method according to claim 3 , wherein before the determining the role of each of the M outbound interfaces, and wherein the method further comprises:
allocating the ECMP group to the second chassis-shaped device.

8 . The method according to claim 7 , wherein the ECMP group comprises a first outbound interface of a first forwarding chip, and wherein the first outbound interface is configured to be connected to the second chassis-shaped device, the first forwarding chip is any one of the N forwarding chips, and the method further comprises:
receiving a first notification message from the first forwarding chip that indicates that the first outbound interface of the first forwarding chip is in a faulty state; and deleting, based on the first notification message, the first outbound interface from the ECMP group in the first forwarding entry.

9 . The method according to claim 8 , wherein in accordance with the outbound interface of the shortest path being in a non-congested state, and wherein the target outbound interface is the outbound interface of the shortest path.

10 . The method according to claim 9 , wherein the M outbound interfaces comprise a plurality of outbound interfaces of the shortest path between the first chassis-shaped device and the second chassis-shaped device,
wherein the plurality of outbound interfaces of the shortest path comprise a local outbound interface and an inter-chip outbound interface, and wherein, in accordance with the local outbound interface and the inter-chip outbound interface each being in a non-congested state;
the target outbound interface is the local outbound interface,
the local outbound interface is an outbound interface of a forwarding chip that receives the first data packet in the first chassis-shaped device, and
the inter-chip outbound interface is an outbound interface of another forwarding chip different from the forwarding chip that receives the first data packet in the first chassis-shaped device.

11 . The method according to claim 1 , wherein in accordance with the outbound interface of the shortest path being in a congested state, the target outbound interface is an outbound interface in a non-congested state in the outbound interface of the non-shortest path.

12 . The method according to claim 11 , wherein in accordance with the outbound interface of the shortest path being in the congested state and a local outbound interface and an inter-chip outbound interface in the outbound interface of the non-shortest path each being in a non-congested state:
the target outbound interface is the local outbound interface in the outbound interface of the non-shortest path, the local outbound interface is an outbound interface of a forwarding chip that receives the first data packet in the first chassis-shaped device, and the inter-chip outbound interface is an outbound interface of another forwarding chip different from the forwarding chip that receives the first data packet in the first chassis-shaped device.

13 . The method according to claim 1 , wherein the N forwarding chips comprise a second forwarding chip, wherein the second forwarding chip comprises a second outbound interface that is configured to be connected to the second chassis-shaped device, and wherein before the selecting a target outbound interface from the M outbound interfaces based on a congested state of each of the M outbound interfaces and a role of each outbound interface, the method further comprises:
receiving a second notification message from the second forwarding chip, wherein the second notification message indicates a congested state of the second outbound interface of the second forwarding chip; and recording the congested state of the second outbound interface based on the second notification message.

14 . The method according to claim 13 , wherein the second notification message is generated by the second forwarding chip in

Assignees

• Huawei Tech Co Ltd

Inventors

• Hao Weiguo
• Pan Yang
• Yu Qingbo
• Li Jun
• Hou Yanxiang

Classifications

• H04L49/30

  Peripheral units, e.g. input or output ports · CPC title

• H04L45/04

  Interdomain routing, e.g. hierarchical routing · CPC title

• H04L45/123

  Evaluation of link metrics (techniques for monitoring network metrics H04L43/08) · CPC title

• H04L45/02

  Topology update or discovery · CPC title

• H04L45/00

  Routing or path finding of packets in data switching networks (routing or path finding in wireless networks H04W40/00) · CPC title