Service chain fault protection method, apparatus, device and system, and storage medium

A network device, applied to a second service function forwarder (SFF) in a service chain, wherein the network device comprises:

• at least one processor;
• and
• one or more memories coupled to the at least one processor and storing programming instructions, wherein the at least one processor is configured to execute the programming instructions, and executing the programming instructions causes the network device to:
• receive a second packet, wherein a destination address field of a packet header of the second packet comprises a first segment identifier (SID), and the first SID is a local segment routing Internet Protocol version 6 (SRv6) SID of the second SFF;
• perform local forwarding processing on the second packet based on the first SID to obtain a fourth packet, wherein the fourth packet comprises a payload of the second packet and does not comprise a segment list;
• and
• send the fourth packet to a first service function (SF) network element in the service chain.

A network device, applied to a first service function forwarder (SFF) in a service chain, the network device comprising:

• at least one processor;
• and
• one or more memories coupled to the at least one processor and storing programming instructions, wherein the at least one processor is configured to execute the programming instructions, and executing the programming instructions causes the network device to:
• receive a fifth packet, wherein a destination address of a packet header of the fifth packet comprises a segment routing Internet Protocol version 6 (SRv6) proxy segment identifier (SID) corresponding to a first SF network element in the service chain, and the first SFF is an SFF accessed by the first SF;
• if the first SF network element is in a faulty state, update the destination address field of the fifth packet to obtain a sixth packet, wherein the destination address of a packet header of the sixth packet comprises a bypass SID, the bypass SID is a local SRv6 SID of a second SFF, the second SFF is an SFF accessed by a second SF network element, the second SF network element is an SF network element other than the first SF network element, and the sixth packet comprises a payload of the fifth packet;
• and
• send the sixth packet.