P4RT-5.3: Cisco fix

[karthikeya-remilla]

Changes done to fix this test:

1. keep per-run OutPkts baselines, program both IPv4 and IPv6 trap entries, validate TTL/HopLimit by received EtherType.
2. Program both IPv4 and IPv6 P4RT redirect rules on the DUT. This ensures that both IPv4-in-IPv4 (matched by IPv4
   rule) and IPv6-in-IPv4 (matched by IPv6 rule) are correctly redirected to the controller.
3. Dynamically decode TTL/HopLimit based on the received packet's actual etherType (IPv4 vs IPv6) instead of
   relying on the hardcoded isIPv4 test parameter.

[gemini-code-assist]

Summary of Changes

Hello, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request introduces critical fixes and platform-specific adjustments to the P4RT traceroute packet-in test suite. The changes focus on improving test reliability through better packet counting, expanding protocol coverage by supporting both IPv4 and IPv6 P4RT rules, and ensuring compatibility with Cisco hardware through necessary configuration deviations.

Highlights

• Test Robustness: Updated packet counting logic to maintain per-run baselines, ensuring accurate traffic validation.
• P4RT Configuration: Modified test to program both IPv4 and IPv6 P4RT redirect rules, improving coverage for IPv4-in-IPv4 and IPv6-in-IPv4 scenarios.
• Dynamic Decoding: Implemented dynamic TTL/HopLimit decoding based on the actual EtherType of received packets instead of relying on hardcoded parameters.
• Cisco Platform Support: Added platform-specific deviations for Cisco devices to handle policy forwarding, ISIS topology, and BGP transport address requirements.

Using Gemini Code Assist

The full guide for Gemini Code Assist can be found on our documentation page, here are some quick tips.

Invoking Gemini

You can request assistance from Gemini at any point by creating a comment using either /gemini <command> or @gemini-code-assist <command>. Below is a summary of the supported commands on the current page.

Feature	Command	Description
Code Review	/gemini review	Performs a code review for the current pull request in its current state.
Pull Request Summary	/gemini summary	Provides a summary of the current pull request in its current state.
Comment	@gemini-code-assist	Responds in comments when explicitly tagged, both in pull request comments and review comments.
Help	/gemini help	Displays a list of available commands.

Customization

To customize the Gemini Code Assist for GitHub experience, repository maintainers can create a configuration file and/or provide a custom code review style guide (such as PEP-8 for Python) by creating and adding files to a .gemini/ folder in the base of the repository. Detailed instructions can be found here.

Limitations & Feedback

Gemini Code Assist may make mistakes. Please leave feedback on any instances where its feedback is incorrect or counterproductive. You can react with 👍 and 👎 on @gemini-code-assist comments. If you're interested in giving your feedback about your experience with Gemini Code Assist for GitHub and other Google products, sign up here.

Footnotes

1. Review the Privacy Notices, Generative AI Prohibited Use Policy, Terms of Service, and learn how to configure Gemini Code Assist in GitHub here. Gemini can make mistakes, so double check it and use code with caution. ↩

[OpenConfigBot]

Pull Request Functional Test Report for #5650 / fb5ea4f

Virtual Devices

Device	Test	Test Documentation	Job	Raw Log
Arista cEOS		P4RT-5.3: Traceroute: PacketIn With VRF Selection
Cisco 8000E		P4RT-5.3: Traceroute: PacketIn With VRF Selection
Cisco XRd		P4RT-5.3: Traceroute: PacketIn With VRF Selection
Juniper ncPTX		P4RT-5.3: Traceroute: PacketIn With VRF Selection
Nokia SR Linux		P4RT-5.3: Traceroute: PacketIn With VRF Selection
Openconfig Lemming		P4RT-5.3: Traceroute: PacketIn With VRF Selection

Hardware Devices

Device	Test	Test Documentation	Raw Log
Arista 7808		P4RT-5.3: Traceroute: PacketIn With VRF Selection
Cisco 8808		P4RT-5.3: Traceroute: PacketIn With VRF Selection
Juniper PTX10008		P4RT-5.3: Traceroute: PacketIn With VRF Selection
Nokia 7250 IXR-10e		P4RT-5.3: Traceroute: PacketIn With VRF Selection

Help

[gemini-code-assist]

Code Review

This pull request introduces several platform-specific deviations and exceptions for CISCO, including single topology requirements for ISIS, interface name usage for IBGP transport, and static ARP overrides. It also refactors packet tracking in packetin_test.go to measure packet differences per flow and loops over IPv4/IPv6 table programming. Feedback on the changes suggests avoiding the use of defer inside the loop in packetin_test.go to prevent resource accumulation and potential linter warnings, recommending sequential programming instead.

[karthikeya-remilla]

/gemini review

[gemini-code-assist]

Code Review

This pull request updates the traceroute packet-in with VRF selection test to support Cisco-specific platform deviations. It adds deviations for ISIS single topology, BGP neighbor transport local address, and GRIBI MAC override with static ARP. Additionally, packetin_test.go is refactored to measure traffic per flow, program both IPv4 and IPv6 ACL entries, and validate TTL/HopLimit based on the Ethernet type. I have no feedback to provide as there are no review comments.

[AmrNJ]

LGTM.