PLAINTEXT-ONLY: the shipped `doca_flow_grpc` server uses `grpc::InsecureServerCredentials()` with NO TLS / mTLS / token-auth knob on the binary — transport security must come from external infrastructure (e.g. an mTLS proxy / sidecar) on a trusted segment. Use this skill when bringing up, configuring, hardening, or debugging `doca_flow_grpc` — the DOCA-shipped gRPC remote-control surface in front of `doca-flow` that lets non-C++ clients (Python, Go, Rust, Java) program Flow pipes and entries over RPC instead of linking `libdoca_flow.so` directly. Trigger even when the user doesn't say 'doca-flow-grpc-server' or 'gRPC' — e.g. 'program Flow rules from Python on another host', 'remotely configure pipes on the BlueField', 'client times out connecting to the Flow server', 'where is the .proto for Flow', 'UNAUTHENTICATED / FAILED_PRECONDITION on a Flow RPC'. Route elsewhere for the underlying doca-flow API, generic gRPC tooling (protoc, language bindings), or DOCA install / BFB bring-up.
PLAINTEXT-ONLY: the shipped `doca_flow_grpc` server uses `grpc::InsecureServerCredentials()` with NO TLS / mTLS / token-auth knob on the binary — transport security must come from external infrastructure (e.g. an mTLS proxy / sidecar) on a trusted segment. Use this skill when bringing up, configuring, hardening, or debugging `doca_flow_grpc` — the DOCA-shipped gRPC remote-control surface in front of `doca-flow` that lets non-C++ clients (Python, Go, Rust, Java) program Flow pipes and entries over RPC instead of linking `libdoca_flow.so` directly. Trigger even when the user doesn't say 'doca-flow-grpc-server' or 'gRPC' — e.g. 'program Flow rules from Python on another host', 'remotely configure pipes on the BlueField', 'client times out connecting to the Flow server', 'where is the .proto for Flow', 'UNAUTHENTICATED / FAILED_PRECONDITION on a Flow RPC'. Route elsewhere for the underlying doca-flow API, generic gRPC tooling (protoc, language bindings), or DOCA install / BFB bring-up.
metadata
{"kind":"tool"}
compatibility
Requires DOCA on Linux (Ubuntu 22.04/24.04 or RHEL/SLES) with a BlueField DPU or ConnectX NIC. The `doca_flow_grpc` binary is a build artifact (install: false in tools/flow_grpc_server/meson.build, gated by flag_enable_grpc_support + flag_enable_grpc_flow_library) — NOT installed under a default DOCA path; build it from the DOCA source tree with gRPC enabled. Its `.proto` lives under libs/doca_flow/grpc/. Confirm Flow via `pkg-config doca-flow`.
DOCA Flow gRPC Server (doca_flow_grpc)
CRITICAL transport-security correction (Run-12 + R13). The
shipped doca_flow_grpc / doca_flow_grpc_client
binaries hard-code the gRPC plaintext credentials surface:
the server uses grpc::InsecureServerCredentials() (the
C++ gRPC server-side API in tools/flow_grpc_server/server/);
the C++ client uses
grpc::InsecureChannelCredentials() (the C++ gRPC
client-side API; the client lives in
libs/doca_flow/grpc/client/, compiled into the
doca_flow library, NOT under tools/flow_grpc_client/);
the Python
client uses grpc.aio.insecure_channel(...). Do NOT cite the
server-side string as grpc::InsecureChannelCredentials() —
that is the client-side API name and a Grep-against-source
verification will fail. There
is no TLS, no mTLS, and no token-auth knob on the shipped
control plane today. Any prose below (or in CAPABILITIES.md
/ TASKS.md) that frames "mTLS / token auth / TLS posture"
as a configurable knob on this server is the bundle's
previous aspirational framing and is wrong against the shipped
source. Treat the server as plaintext-on-a-trusted-segment
only: it MUST be bound on a control-plane-only network
segment behind an external proxy, sidecar, or VPN
that itself enforces TLS + identity. Any "TLS / mTLS / token-
auth" discussion below is about the operator's external
hardening layer, NOT a knob on this binary. Routing for an
TLS / identity design discussion must stay on the selected
external proxy, sidecar, or VPN; never route it to a
shipped-today binary knob.
Where to start: This is a tool skill for standing up and
operating doca_flow_grpc, the DOCA-shipped gRPC remote-
control surface for doca-flow. Open TASKS.md and
start at ## configure to decide whether a
remote control plane is the right answer at all (vs talking to
libdoca_flow.so directly), then ## run for
the start → bind → one-client-smoke sequence, then
## test for the smoke-before-bulk loop that
gates any RPC that mutates Flow / dataplane state. Open
when the question is (the files shipped
under the tool's source tree on the user's install), , , or . If DOCA is
not installed, route to
first; if the user has
not stood up yet, route to
FIRST — the gRPC
server is a remote control plane on top of the Flow library, not
a replacement for it.
The CLASSES of doca_flow_grpc questions this skill is
built to answer, each with one worked example. The class is the
load-bearing piece; the worked example is one instance.
"Do I actually need a remote control plane for my Flow
pipeline, or should my client just link libdoca_flow.so
directly?" — worked example: "my client is a Python
service on a different host; can it program Flow rules
remotely?". Answered by the when-to-use-gRPC decision in
CAPABILITIES.md ## Capabilities and modes
the routing into
doca-flow when a direct
library link is the better answer.
"Where is the gRPC contract surface actually defined on my
install?" — worked example: "I want to generate a Python
client; where do I get the .proto file?". Answered by the
the-.proto-file-is-the-source-of-truth rule in
CAPABILITIES.md ## Capabilities and modes
the language-bindings discussion of standard gRPC tooling
(protoc + the language-specific gRPC plugin per the
official gRPC docs on grpc.io).
"How do I harden the gRPC endpoint so it isn't an open
door into my dataplane?" — worked example: "the server is
bound on 0.0.0.0; what should I do before exposing it?".
Answered by the admin attack surface posture in
CAPABILITIES.md ## Safety policy
"How do I smoke ONE client end-to-end before opening the
server to the fleet?" — worked example: "my Python client
can dial the endpoint; what is the first RPC I run to prove
it talks to the live Flow application?". Answered by the
smoke-before-bulk loop in
TASKS.md ## test +
CAPABILITIES.md ## Safety policy
smoke-before-bulk rule.
"My client cannot reach the server — is the server down,
the wrong endpoint, an external-proxy mismatch, or a version
mismatch?" — worked example: "the client times out
connecting". Answered by the layered error taxonomy in
CAPABILITIES.md ## Error taxonomy
"Is my non-C++ client (Python / Go / Rust) actually the
right shape for the gRPC contract, or is there a cleaner
path?" — worked example: "I want a Rust client; what
does the .proto-generated API look like?". Answered by the
language-bindings discussion in
CAPABILITIES.md ## Capabilities and modes
the routing through standard gRPC tooling.
Audience
This skill serves external operators, control-plane developers,
and AI agents who need to program a running DOCA Flow pipeline
from a non-C++ process across a network boundary instead of
linking libdoca_flow.so directly into the controlling process.
Concretely:
A control-plane engineer writing a Python / Go / Rust client
that programs Flow rules on a BlueField from outside the
BlueField's address space.
A platform operator running a Flow-using service on
BlueField who wants to expose a remote-control surface to a
centralized control plane.
An AI agent driving the "can I program these Flow rules
from this client / this network position" triage step
before recommending a code change to the surrounding
doca-flow application.
It is not for users debugging the gRPC server's source code,
not a substitute for the live public DOCA Flow gRPC Server
guide on docs.nvidia.com, and not the place to learn the
doca-flow API — that audience belongs in
doca-flow.
doca_flow_grpc is a single CLI binary built from the DOCA
source tree (executable('doca_flow_grpc', ..., install: false)
in tools/flow_grpc_server/meson.build, gated by
flag_enable_grpc_support), plus its companion .proto
contract files under libs/doca_flow/grpc/; per the tool's
source tree (server/, dpa_device/, packet_buffering/) the
tool can also be paired with a packet-buffering / DPA-side
helper on configurations that need them. The skill uses the
same kind: tool three-file shape (SKILL.md + CAPABILITIES.md + TASKS.md) the rest of the bundle's tool slot uses — front matter at the top of this file already says kind: tool. (Prior bundle revisions said "library three-file shape" here; that wording was internally inconsistent with the front matter and is corrected.)
Language scope
This skill governs deployment, configuration, hardening, and
client-side bring-up across the languages standard gRPC tooling
covers — Python, Go, C++, Rust, Java, Node.js, C#, Kotlin, Ruby,
PHP, Dart — via the language-specific gRPC plugin generated
from the shipped .proto files (see the
gRPC language support index
on grpc.io). The server itself is C++ + DOCA; the client
languages are open, gated only by the standard protoc plugin
set. For the doca-flow API the server programs, see
doca-flow — that surface is
C-language.
When to load this skill
Load this skill when the user is — or the agent needs to — bring
up doca_flow_grpc against a running doca-flow
application (or its preconditions) and connect a non-C++ client
to it. Concretely:
Deciding whether a remote gRPC control plane is the right
surface (vs a direct libdoca_flow.so link in the client
process).
Locating the .proto files on the user's install so a
language-binding client can generate the appropriate
stubs.
Deciding the deployment's transport-security posture and
network segment. NOTE: the shipped server is plaintext-only
(grpc::InsecureServerCredentials()); TLS / mTLS / token-auth
are NOT binary configuration knobs — they are external
infrastructure concerns handled by a capable proxy, sidecar,
or VPN, and the
plaintext endpoint must stay on a trusted, isolated segment.
Standing up the server alongside a known-good Flow setup
and smoke-testing one client end-to-end before exposing
the endpoint to the fleet.
Diagnosing a connect / version / RPC failure through the
layered taxonomy.
Do not load this skill for general DOCA orientation,
doca-flow API work, DOCA install, or general gRPC tooling
(use the grpc.io docs directly for those).
What this skill provides
This is a thin loader. Substantive material lives in two
companion files:
CAPABILITIES.md — what doca_flow_grpc exposes:
the gRPC remote-control surface in front of doca-flow,
the .proto-files-as-authoritative-contract rule (the
shipped .proto files under the tool's source on the
user's install are the source of truth), the when-to-use-
gRPC vs direct-library-link decision, the language-
bindings story (any language standard gRPC tooling covers),
the external proxy / sidecar / VPN and network-segment decision, the
packet-buffering / DPA-side option per the shipped
packet_buffering/ and dpa_device/ subtrees, the
version overlay (server rides the doca-flow library
version it links against), the layered error taxonomy
(server-not-started / server-binding-failed / external-layer-
rejected / RPC-call-error / Flow-precondition-failed /
version / cross-cutting), the observability surface (the
server's own logs + the live Flow application's logs +
the RPC client's status codes), and the safety policy
that treats the endpoint as an admin attack surface.
TASKS.md — step-by-step workflows for the in-scope task
verbs: install (route to setup; binary is built from
source with gRPC support enabled),
configure (decide remote-vs-direct, pick the external
proxy / sidecar / VPN and network segment), build (route to install),
modify (refuse — modify the deployment, not the binary),
run (start → bind → smoke), test (the
smoke-before-bulk loop with the client-side stub
generation step), debug (the layered diagnosis ladder),
use (the agent-side workflow for consuming a captured
gRPC server session), plus a Deferred task verbs block
and a Command appendix.
The skill assumes a host where DOCA is already installed (or
the NGC DOCA container is running) with the Flow library
present, a working doca-flow application to program against,
and the operator's awareness that exposing a gRPC control plane
is a high-stakes posture.
What this skill deliberately does not ship
This skill is agent guidance, not a samples or scripts
bundle. To keep the boundary clean, it deliberately does not
contain — and pull requests should not add:
Verbatim RPC method names, message field inventories, or
default endpoint paths. The .proto files shipped under
the tool's source tree on the user's install are the
authoritative contract; copying them here pins the skill
to one release and silently rots when the contract
evolves.
Pre-baked client code in any language. The
language-specific gRPC plugin + the shipped .proto files
are the contract; client code generated from them on the
user's installed version is the right answer, not a stub
pinned to a snapshot.
A pre-baked external security-layer configuration. CA,
token, and mTLS configuration belong to the selected proxy,
sidecar, or VPN and its security review, never to
doca_flow_grpc.
Wrappers, parsers, or scripts that proxy the gRPC
endpoint into another protocol. The endpoint is the
endpoint; if a user wants HTTP/JSON instead, that is a
separate concern outside this skill's scope.
A samples/, bindings/, or reference/ subtree.
Even one labeled "reference" is misleading: operators
will read it as buildable.
Loading order
Read this SKILL.md first to confirm the user's question
is in scope (the user actually wants a remote gRPC control
plane on top of doca-flow, not a direct library link or
a different DOCA library).
For what the server exposes, the .proto-as-contract
rule, the language-bindings story, the external proxy /
sidecar / VPN and network-segment decision, version availability, the
layered error surface, observability, and safety posture,
see CAPABILITIES.md.
For the documented start sequence and the
smoke-before-bulk workflow — install, configure,
build, modify, run, test, debug, use — see
TASKS.md.
Related skills
doca-flow — the base
library the server's gRPC contract is a thin remote-
control wrapper over. Pipe / entry / rule semantics, the
validate-before-commit rule, the Flow counter / inspector
surface all live there.
doca-flow-tune — the Flow
tuning tool. When a Flow-program change is recommended,
the change can be applied through the surrounding
application or — when the control plane is remote —
through this gRPC server's RPC surface.
doca-public-knowledge-map
— routing to the public DOCA Flow gRPC Server page on
docs.nvidia.com and the rest of the public DOCA
documentation set.
doca-debug — the cross-cutting
debug ladder. gRPC server failures route into the ladder at
the runtime layer.
doca-setup — env preparation,
install verification, and the NGC DOCA container path.
doca-hardware-safety —
the cross-cutting hardware-safety meta-policy this skill's
## Safety policy overlays. Any state-changing RPC is a
potential dataplane-affecting change and must respect the
meta-policy.
