Network node-to-node connectivity verification including data path processing of packets within a packet switching device

Patent metadata

Field	Value
Publication number	US-11824753-B2
Application number	US-202117446965-A
Country	US
Kind code	B2
Filing date	Sep 5, 2021
Priority date	Sep 5, 2021
Publication date	Nov 21, 2023
Grant date	Nov 21, 2023

Abstract

In one embodiment, network node-to-node connectivity verification is performed in a network including data path processing of packets within a packet switching device. In one embodiment, an echo request connectivity test packet, emulating an echo request connectivity test packet received from a first connected network node, is inserted by the packet switching device prior in its data processing path prior to ingress processing performed for packets received from the first connected network node. A correspondingly received echo reply connectivity test packet is intercepted by the packet switching device during data path egress processing performed for packets to be forwarded to the first connected network node.

First claim

What is claimed is:

1. A method, comprising:
receiving, on an ingress port of a plurality of ingress ports of a packet switching device, a first plurality of packets being sent in a network from a first network node through the packet switching device to a second network node, with each packet of the first plurality of packets including, in a header, a source address of the first network node and a destination address of the second network node;
creating, by the packet switching device, a second plurality of packets including one or more test echo request packets and the first plurality of packets, with each test echo request packet of the one or more test echo request packets including in a header, the source address of the first network node and the destination address of the second network node; and
for each packet of the second plurality of packets, a first network processor of a plurality of network processors of the packet switching device packet performing ingress processing on the respective packet including identifying a forwarding result, and sending the respective packet from the packet switching device after performing egress processing of the respective packet by a second network processor of the plurality of network processors -identified based on the forwarding result,
wherein the first network processor performs ingress processing on the one or more test echo request packets in response to the packet switching device ascertaining the first network processor will be processing the first plurality of packets or has processed at least one of the first plurality of packets,
wherein each of the second plurality of packets includes a network layer protocol packet, with the source address being a network protocol source address of the first network node, and with the destination address being a network protocol destination address of the second network node, and
wherein each of the second plurality of packets includes a data link layer packet encapsulation of the network layer protocol packet, with the data link layer packet including a data link level source address of the first network node and a data link level destination address of the second network node.

2. The method of claim 1 , wherein the creating one or more test echo request packets is performed by the first processor of the packet switching device; and
wherein the method comprises the packet switching device response to ascertaining the first network processor will be processing the first plurality of packets or has processed at least one of the first plurality of packets, is communicating the one or more test echo request packets to the first network processor.

3. The method of claim 1 , wherein the network layer protocol packet is Internet Protocol version 4 (IPv4) or Internet Protocol version 6 (IPv6).

4. The method of claim 1 , each of the plurality of test echo request packets uses Internet Control Message Protocol (ICMP) or IPv6 Internet Control Message Protocol (ICMPv6).

5. The method of claim 1 , further comprising:
intercepting, but not forwarding to the first network node, each echo reply connectivity test packet received by the packet switching device and corresponding to a sent one of the one or more test echo request packets, with the echo reply connectivity test packet including in a header, a source address of the second network node and a destination address of the first network node.

6. The method of claim 5 , wherein at least one of the first plurality of packets includes a first node-generated test echo request packet being sent in the network from the first network node through the packet switching device to the second network node; and
wherein the method comprises packet processing each specific reply packet corresponding to the sent first node-generated test echo request packet received by the packet switching device, with the echo reply connectivity test packet including in a header, a source address of the second network node and a destination address of the first network node, and with the packet processing including forwarding the specific reply packet to the first network device.

7. The method of claim 6 , wherein egress processing by a specific network processor of the plurality of network processors performs the intercepting, with the specific network processor associated with an egress port from which the packet switching device sends packets to the first network device.

8. The method of claim 5 , wherein egress processing by a specific network processor of the plurality of network processors performs the intercepting, with the specific network processor associated with an egress port from which the packet switching device sends packets to the first network device.

9. The method of claim 8 , further comprising configuring an access control list associated with the egress port to cause the intercepting of the each echo reply connectivity test packet received by the packet switching device and corresponding to the sent one of the created one or more test echo request packets.

10. The method of claim 8 , wherein the egress processing of the respective packet includes Virtual eXtensible Local Area Network (VXLAN) or VXLAN Generic Protocol Extension (VXLAN-GPE) encapsulation; and
wherein the method includes the packet switching device removing VXLAN or VXLAN-GPE encapsulation of a received packet revealing the echo reply connectivity test packet received by the packet switching device and corresponding to the sent one of the created one or more test echo request packets.

11. The method of claim 8 , further comprising configuring a filtering mechanism associated with the particular egress port to cause the intercepting of said each particular echo reply connectivity test packet received by the packet switching device and corresponding to the sent one of the created one or more test echo request packets.

12. A method, comprising:
responsive to a selecting a pairing of a plurality of first network nodes with plurality of second network nodes, a packet switching device performing connectivity testing of the pairing;
wherein the selecting operation is repeatedly performed such that each of the plurality of first network nodes with the plurality of second network nodes is selected one or more times;
wherein the connectivity testing of the pairing includes the packet switching device creating a test echo request packet including in a header, a source address of a respective first network node of the pairing and a destination address of a respective second network node of the pairing, and emulating packet processing of the test echo request packet as if it was received over the network from the respective first network node, with the packet processing including ingress processing, egress processing, and sending the test echo request packet into the network;
wherein the connectivity testing of the pairing includes the packet switching device egress processing each received echo reply connectivity test packet corresponding to the sent test echo request packet, with the received echo reply connectivity test packet including in a header, a source address of the respective second network node and a destination address of the respective first network node, and with the egress processing being performed by a network processor designated to egress processing packets being sent to the respective first network node, with the egress processing including intercepting and processing the received particular reply connectivity test packet without forwarding the received echo reply connectivity test packet to the respective first network node, with the processing includes updating one or more data struct

Assignees

• Cisco Tech Inc

Inventors

• Venkatraman Rajagopal
• Kumar Rajeev
• Kobo Roberto Mitsuo
• Agarwal Vikash

Classifications

• H04L43/12 Primary

  Network monitoring probes · CPC title

• H04L45/02

  Topology update or discovery · CPC title

• H04L45/74

  Address processing for routing · CPC title

• H04L43/50 Primary

  Testing arrangements · CPC title

• H04L43/10

  Active monitoring, e.g. heartbeat, ping or trace-route · CPC title