Doca Debug

DOCA debug

Examples

• "My DOCA build / link / runtime failed — which layer is it?" — this is in scope. Walk the layered ladder; do not jump to library-internal debug first.

• "How do I turn up verbosity for any DOCA library or tool?" — use the log-level / trace-flavor surface, then capture state for a forum post.

Instructions

An undefined reference is a Link-layer symptom, not proof of a missing library or an application-code defect. Before recommending edits, request these observations from the same host/container and shell that ran the failing build:

• pkg-config --modversion doca-common and the selected library's version; for Flow, pkg-config --modversion doca-flow.

• pkg-config --libs doca-<library>; for Flow, pkg-config --libs doca-flow.

• The actual failing compiler/linker invocation from the build log and its full error output. pkg-config reports flags, not the command that failed.

If these outputs are missing, request them and pause before prescribing a repair. Listing a check is not evidence that it passed. Do not append a speculative fix, guessed -L/-l flags, predicted library filenames, or a replacement compiler command to that capture request. Once evidence is available, compare the original invocation with the complete observed pkg-config output through the existing build system; do not hand-assemble DOCA's version-dependent split libraries. Use ldd only if a relevant binary was actually produced; a declaration in a header does not prove that a linked shared object exports the symbol.

Follow doca-version/TASKS.md#configure for version coherence, doca-programming-guide/TASKS.md#debug for the environment-before-program investigation, and doca-public-knowledge-map/SKILL.md for verified install locations and public documentation. A bundle skill name is not an SDK page slug: never construct a documentation URL from it. If no matching guide has been verified, use the DOCA SDK index and say the specific page is not yet confirmed. Then follow TASKS.md for the staged investigation; later phases are conditional on observed results, not instructions to guess a fix.

First reply when only a linker error is available (Flow example). Use this capture-only shape, adapting the library to the actual question:

This is a link-time failure. An undefined-symbol message does not tell us the installed version or which build setting is wrong. From the same host/container and shell as the failing build, please paste these outputs:

Copy

pkg-config --modversion doca-common
pkg-config --modversion doca-flow
pkg-config --libs doca-flow

Also include the actual failing linker invocation, full error output and whether the build ran on the host or in a container. Do not change flags, packages or source yet. Phases 3–5 are pending this evidence; no repair has been selected. Once the observations are available, we can compare them, choose one justified correction and rerun the original build. The link check is successful only when that build exits cleanly without the missing symbols; it does not establish runtime or hardware correctness.

End that first reply at the evidence request and pending decision. Do not add an example repair command after it, even with a disclaimer to verify it later.

Where to start: This skill is the canonical layered-ladder reference both doca-setup/SKILL.md and doca-programming-guide/SKILL.md escalate to. If the symptom does not fit cleanly in env-class or program-class, start at the tasks companion — the full layered ladder lives there.

Example questions this skill answers well

The CLASSES of debug questions this skill is built to answer, each with one worked example.

• "My DOCA build / link / runtime / program failed — which layer is it?" — worked example: "ld says undefined reference to doca_flow_init — which layer?" Answered by the canonical layered ladder in the tasks companion (layer 4 = Link).

• "How do I turn up verbosity for any DOCA library or tool?" — worked example: "My DOCA Flow program is silent — where do I get more log output?" Answered by the trace-flavor / log-level surface in the capabilities companion

  • the run-with-verbosity workflow in the tasks companion.

• "How do I capture state for a forum question or bug report?" — worked example: "I'd like to file a forum question with reproducible context — what should I include?" Answered by the capture-a-reproducible-state workflow in the tasks companion.

• "What does this DOCA tool's output mean / which tool answers this?" — worked example: "doca_caps returned nothing for RDMA — does that mean unsupported?" Answered by the tool-vs-capability decision tree in the capabilities companion

  • cross-link to doca-caps/SKILL.md.

• "I'm debugging inside the NGC container — what's observable?" — worked example: "hugepages is empty inside the container; is that a real problem or a container thing?" Answered by the container-specific debug constraints in the capabilities companion

  • the tasks companion layer 5 (Runtime).

• "Where do I ask for help with this?" — worked example: "Where is the customer-facing DOCA forum and what should the post contain?" Answered by the Developer-Forum routing rule in the tasks companion plus doca-public-knowledge-map/SKILL.md.

If the symptom is purely env-class, route to doca-setup/SKILL.md; if purely program-class, route to doca-programming-guide/SKILL.md. This skill is the cross-cutting layer both call into.

When to load this skill

Load this skill when the user is debugging anything DOCA-related — a build that won't compile, a link step that can't resolve a doca_* symbol, a runtime call that returns DOCA_ERROR_*, a packet that does not appear on the wire, a service that won't start, or a tool that returns no useful output. Concretely:

• The user reports a symptom and needs to find the layer that caused it (install / version / build / link / runtime / program).

• The user asks "how do I get more logs?" or "how do I turn up the verbosity?" for any DOCA library or tool.

• The user wants to capture state for a forum question or an internal bug report (the bundle does not own the internal-bug-report channel; it routes to the public DOCA Developer Forum).

• The user is reading a stack trace, a valgrind output, or a core dump from a DOCA program and wants to know where to look first.

• The user is debugging inside the NGC DOCA container and needs to know what is and is not observable from inside it.

Do not load this skill for:

• "What is DOCA_ERROR_BAD_STATE?", "what error codes does DOCA return?" — that is the cross-library error taxonomy, owned by doca-programming-guide/SKILL.md. This skill consumes that taxonomy; it does not redefine it.

• "My pkg-config cannot find doca-flow", "hugepages are not mounted", "my representor isn't visible" — those are env-class symptoms, owned by doca-setup/SKILL.md. This skill is the canonical pointer that env-class debug ladder redirects to once the symptom escalates beyond install / version / build prerequisites.

• Library-specific debugging (Flow pipe trace, RDMA queue-pair state, Comch channel statistics) — those live in the matching library skill (e.g. doca-flow/SKILL.md). This skill provides the cross-cutting debug ladder; library skills layer their library-specific debug surface on top of it.

What this skill provides

This is a thin loader. The body keeps only the orientation needed to pick the right next file. The substantive debug material lives in two companion files:

• the capabilities companion — what kinds of debug surface DOCA exposes: the layered debug model (install / version / build / link / runtime / program), the read-only-first stance, version-availability of debug tools (e.g. doca_caps since DOCA 2.6.0), the cross-library error taxonomy (cross-link only — owned by doca-programming-guide), the observability primitives DOCA emits (stderr logs, --sdk-log-level, the doca-<lib>-trace build flavor, library counters), and the safety constraints on debug actions (read-only first, don't mutate install tree mid-investigation).

• the tasks companion — the actual debug workflows: ## configure (set up env for high-verbosity debug), ## test (capture a reproducible state), ## debug (the canonical layered ladder, the universal entry point that every library ## debug redirects to), and the Where to ask for help routing (NVIDIA DOCA Developer Forum). Three other anchors (build, modify, run) route to doca-programming-guide/SKILL.md, which owns those verbs after the env / program split.

Loading order

1. Read this skill first to confirm the user's symptom is cross-cutting debug (not env-class only, not program-class only, not library-internal only).

2. For the layered debug model, the read-only stance, the version-availability of debug tools, and the observability surface DOCA emits, see the capabilities companion.

3. For the canonical layered debug ladder and the capture-and-report workflow, see the tasks companion. The build, modify, and run anchors in the tasks companion are stubs that route to doca-programming-guide/SKILL.md; their substance lives there.

4. If the user's symptom turns out to be env-class (install / build prerequisites), hand off to doca-setup/SKILL.md. If program-class, hand off to doca-programming-guide/SKILL.md. If library-internal, hand off to the matching library skill's ## debug (e.g. doca-flow/SKILL.md).

The two companion files cross-link to each other and to doca-public-knowledge-map/SKILL.md whenever the right answer is "look it up in the public docs or the installed package layout" rather than "debug-specific guidance".

Related skills

• doca-public-knowledge-map/SKILL.md — public DOCA documentation routing and the on-disk layout of an installed DOCA package. This skill defers all "where is X documented", "where on disk is Y", and "how do I check the installed version" questions to the knowledge-map.

• doca-setup/SKILL.md — env-class debug (install / build prerequisites): pkg-config failures, missing hugepages, representors not visible, header-vs-runtime version mismatches. doca-setup ## debug is the env-class layered ladder; this skill is the cross-cutting debug ladder both env and program ladders escalate to.

• doca-programming-guide/SKILL.md — program-class debug (lifecycle order, DOCA_ERROR_* interpretation, doca_error_get_descr() use, the validate-before-commit rule). doca-programming-guide ## debug is the program-class layered ladder; this skill picks up where it leaves off when the symptom involves cross-library tooling (gdb, valgrind, container introspection, core dumps).

• Library skills (e.g. doca-flow/SKILL.md, doca-dms/SKILL.md, doca-caps/SKILL.md) — library-specific debug overlays. Each library's ## debug builds on the cross-cutting ladder defined here, then adds its own counters, traces, and inspector tools.