SRv6 and SRv6-TE Traffic Sensor Telemetry

Segment Routing over IPv6 (SRv6) telemetry support provides a powerful mechanism for monitoring and optimizing network performance. By leveraging the native SRv6 data model, you can integrate telemetry tools that provide comprehensive insights into network traffic. These insights are gathered using streaming XPath from the SRv6 Manager and rpd, which collect and transmit detailed traffic statistics. SRv6 telemetry helps maintain stable network performance and security. It enables monitoring of real-time traffic patterns, detection of anomalies, and prompt responses to potential issues.

The telemetry support for SRv6 provides a unified data model for both SRv6 and SRv6 TE tunnels. This standardization enables consistent management and monitoring of different tunneling technologies within users’ networks. Although the current implementation focuses on SRv6 TE tunnels, the foundation is present for broader support in future updates. The data model ensures consistency, enabling telemetry configuration and management across various network segments.

To enable effective traffic monitoring, traffic sensors are installed on routes and next hops within the rpd. These sensors are mapped to ISIS and SRTE sensors, allowing the Packet Forwarding Engine (PFE) to collect and stream traffic statistics. This integration provides detailed visibility into network performance, enabling proactive management and troubleshooting. By monitoring traffic at a granular level, you can optimize routing decisions, improve network efficiency, and enhance overall operational reliability.

Following are some of the functionalities of SRv6 in telemetry:

• Traffic Statistics telemetry for IGP (ISIS Only) Routes / NextHops: Following is the list of PFE sensors, which are installed by IS-IS based upon the newly introduced configuration commands and streamed by PFE.

  Table 1: Traffic Statistics telemetry for IGP Routes or NextHops.

  Sensor Path	Description
  /state/routing-instances/routing-instance[name]/protocols/source-packet-routing/srv6/remote-locators/remote-locator[address]/counters/in-pkts/state/routing-instances/routing-instance[name]/protocols/source-packet-routing/srv6/remote-locators/remote-locator[address]/counters/in-octets	This sensor path is applicable for PFE sensor for Remote SRv6 locator routes in INET6.0 RT.
  /state/routing-instances/routing-instance[name]/protocols/source-packet-routing/srv6/remote-locators/remote-locator[address]/counters/out-pkts/state/routing-instances/routing-instance[name]/protocols/source-packet-routing/srv6/remote-locators/remote-locator[address]/counters/out-octets	This sensor path is applicable for PFE sensor for Remote SRv6 Locator Route TCNH Gateway in INET6.3 RT.

• Support for Uniformed Native Data Model for SR-TE: This feature includes a model tree for both colored and uncolored policies. Only SRv6-TE FIB Xpaths (traffic counter) with ingress counters are supported for both tunnel types. SRv6 TE traffic counter Xpaths streaming is platform-dependent, applicable only to JUNOS MX platforms. At PFE, stats accounting occurs before policy application, supporting only ingress counters. SRv6-TE sensors support only the DEFAULT instance.

• Colored SRv6-TE per policy ingress counters: The supported counters are listed here-

  Table 2: Colored SRv6-TE per-policy Ingress Counters

  Sensor Path	Description
  /state/routing-instances/routing-instance[name]/protocols/source-packet-routing/te-policies/te-policy[color endpoint]/counters/srv6/in-bytes	This sensor path is applicable for per-policy level PFE sensors pfor SRv6 SR-TE route TCNH gateway in junos-rti table.
  /state routing-instances/routing-instance[name]/protocols/source-packet-routing/te-policies/te-policy[color endpoint]/counters/srv6/in-pkts	This sensor path is applicable for ingress SRv6 traffic.

  Note:

  When per-policy counters are streamed, the values are cumulative of all the candidate-paths of that policy.

• Colored SRv6-TE per path ingress counters: The supported counters are listed here-

  Table 3: Colored SRv6-TE per-path Ingress Counters

  Sensor Path	Description
  /state/routing-instances/routing-instance[name]/protocols/source-packet-routing/te-policies/te-policy[color endpoint]/candidate-paths/candidate-path[protocol-origin originator-asn originator-address discriminator]/segment-lists/segment-list[segment-id]/counters/in-bytes	This sensor path is applicable for per-path level PFE sensors for SRv6 SR-TE route TCNH gateway in junos-rti table.
  /state/routing-instances/routing-instance[name]/protocols/source-packet-routing/te-policies/te-policy[color endpoint]/candidate-paths/candidate-path[protocol-origin originator-asn originator-address discriminator]/segment-lists/segment-list[segment-id]/counters/in pkts	This sensor path is applicable for ingress SRv6 traffic.

• Uncolored SRv6-TE per tunnel ingress counters: The supported counters are listed here-

  Table 4: Uncolored SRv6-TE per-tunnel Ingress Counters

  Sensor Path	Description
  /state/routing-instances/routing-instance[name]/protocols/source-packet-routing/uncolored-te-tunnels/uncolored-te-tunnel[name]/counters/in-bytes	This sensor path is applicable for per-policy level PFE sensors for SRv6 SRTE uncolored route TCNH gateway in inet6.3 table.
  /state/routing-instances/routing-instance[name]/protocols/source-packet-routing/uncolored-te-tunnels/uncolored-te-tunnel[name]/counters/in-pkts	This sensor path is applicable for ingress SRv6 traffic.

• Uncolored SRv6-TE per path ingress counters: The supported counters are listed here-

  Table 5: Uncolored SRv6-TE per-path Ingress Counters

  Sensor Path	Description
  /state/routing-instances/routing-instance[name]/protocols/source-packet-routing/uncolored-te-tunnels/uncolored-te-tunnel[name]/segment-lists/segment-list[segment-id]/counters/in-bytes	This sensor path is applicable for per-path level PFE sensors for SRv6 SRTE uncolored route TCNH gateway in inet6.3 table.
  /state/routing-instances/routing-instance[name]/protocols/source-packet-routing/uncolored-te-tunnels/uncolored-te-tunnel[name]/segment-lists/segment-list[segment-id]/counters/in-pkts	This sensor path is applicable for ingress SRv6 traffic.