name: otel-collector
description: OpenTelemetry Collector component configuration. Use when authoring, reviewing, or debugging Collector YAML for a specific receiver, processor, exporter, connector, or extension — config keys, defaults, validation rules, signal support, stability levels, and component-level gotchas. Triggers on questions about specific components such as log_dedup / logdedup, interval (metric aggregation), tail_sampling, drain, redaction, filter, transform, probabilistic_sampler, attributes, resource, k8s_attributes / k8sattributes (Kubernetes metadata enrichment), routing (connector — route telemetry to pipelines by OTTL condition), memory_limiter (OOM safety valve / backpressure), load_balancing / loadbalancing (trace-ID/service-aware exporter that pins related telemetry to one backend, for scaling tail_sampling), otlp receiver (the canonical OTLP/gRPC + OTLP/HTTP ingress; localhost vs 0.0.0.0 default), otlp / otlp_grpc exporter (OTLP/gRPC egress with sending_queue.batch, retry_on_failure; renamed from otlp), file_log / filelog receiver (tail and parse log files via stanza operators; start_at, multiline, offset tracking), resource_detection / resourcedetection (auto-detect host/cloud/k8s/env resource attributes via detectors), file_storage (storage extension — persist receiver read offsets, exporter persistent send queues, and processor decision caches to local disk via bbolt so they survive a restart), prometheus receiver (scrape Prometheus-format endpoints into OTLP metrics via an embedded prometheus/prometheus scrape manager; scrape_configs, target_allocator, trim_metric_suffixes, native histograms), prometheus exporter (expose pipeline metrics on a /metrics HTTP endpoint for a Prometheus server to scrape — pull not push, contrast prometheusremotewrite; endpoint, namespace, const_labels, metric_expiration, add_metric_suffixes/translation_strategy, enable_open_metrics), prometheus_remote_write / prometheusremotewrite exporter (push OTLP metrics to Prometheus Remote Write backends like Cortex/Mimir/Thanos — contrast the pull-based prometheus exporter; renamed in v0.154.0, RW1 by default with RW2 behind a feature gate, TLS-on default, snappy-only, remote_write_queue, external_labels, wal), and other Collector components covered in components/.
OpenTelemetry Collector
This skill covers the configuration surface of individual OpenTelemetry Collector components. It targets opentelemetry-collector and opentelemetry-collector-contrib.
It does not cover OTTL expressions (see otel-ottl), declarative SDK configuration (otel-declarative-config), or end-to-end pipeline design choices. Reach for those skills when the question is about transformation language, SDK setup, or pipeline composition.
Workflow
- Identify the component. Find the
typein the user's config or question (log_dedup,interval,otlp, …). Note that several components were renamed to snake_case in v0.150.0–v0.151.0 with deprecated aliases preserved — see Recent renames. - Load the component page. If the component is in the Component index, read
components/<type>/README.mdfirst — it carries the metadata, description, main use-cases, and a Details index. Open the linked detail files (configuration.md,verification.md,advanced.md,quirks.md, …) only as the question requires; don't load files you don't need. - If the component is not indexed, say so explicitly and fall back to the upstream README under
processor/<name>/,receiver/<name>/,exporter/<name>/,connector/<name>/, orextension/<name>/in opentelemetry-collector-contrib. Don't invent config keys from memory — Collector components evolve quickly. - Apply Collector-wide conventions. Named instances (
type/name), stability levels, and pipeline placement rules in Collector-wide conventions apply to every component. - Verify. Run the component page's Verification recipe —
telemetrygen(see theotel-telemetrygenskill) plus adebugorfileexporter — to confirm the component behaves as the docs claim. Alpha- and Development-stability components are common here, and behavior changes between releases. See Verification harness for how to run a recipe end-to-end.
Component index
Each component is a directory under components/<type>/. The File column points at the lean README.md (metadata, description, main use-cases, and a Details index); the full config reference, verification recipe, advanced use-cases, and quirks live in on-demand detail files linked from that README.
| Type | File | Kind | Signals | Stability | Summary |
|---|---|---|---|---|---|
log_dedup |
components/log_dedup/README.md |
processor | logs | Alpha | Deduplicates identical log records over a time window; emits one aggregated log with a count. Renamed from logdedup in v0.151.0; alias preserved. |
interval |
components/interval/README.md |
processor | metrics | Alpha | Buffers cumulative monotonic metrics (and optionally gauges/summaries) and emits the latest value once per interval. Delta and non-monotonic sums pass through unchanged. |
tail_sampling |
components/tail_sampling/README.md |
processor | traces | Beta | Buffers whole traces and makes a single keep/drop decision after a wait window via policies. Requires a loadbalancing layer to scale across instances. |
drain |
components/drain/README.md |
processor | logs | Alpha | Clusters log bodies with the Drain algorithm and annotates each record with a derived template string. |
redaction |
components/redaction/README.md |
processor | traces, logs, metrics | Beta (traces), Alpha (logs/metrics) | Allow/block-list masking or removal of sensitive attribute keys and values, with hashing and URL/DB sanitizers. |
filter |
components/filter/README.md |
processor | traces, metrics, logs | Alpha | Drops spans, metric data points, and log records that match OTTL conditions (or legacy metric-name / severity filters). The most direct telemetry-volume lever. |
transform |
components/transform/README.md |
processor | traces, metrics, logs | Beta | Applies OTTL statements to mutate spans, metric data points, and log records in place (rename/redact/convert/aggregate attributes). The OTTL language itself lives in the otel-ottl skill. |
probabilistic_sampler |
components/probabilistic_sampler/README.md |
processor | traces, logs | Beta (traces), Alpha (logs) | Head sampling — deterministically keeps a configured percentage of traces/logs by hashing the trace ID (or an attribute). The cheaper, stateless counterpart to tail_sampling. |
attributes |
components/attributes/README.md |
processor | traces, metrics, logs | Beta | Modifies span/log/datapoint attributes via an ordered action list (insert/update/upsert/delete/hash/extract/convert), scoped by include/exclude matching. |
resource |
components/resource/README.md |
processor | traces, metrics, logs, profiles | Beta (traces/metrics/logs), Development (profiles) | Modifies the resource attributes of telemetry via the same action grammar as attributes (e.g. set service.name, drop noisy resource keys). No include/exclude matching. |
k8s_attributes |
components/k8s_attributes/README.md |
processor | traces, metrics, logs, profiles | Beta (traces/metrics/logs), Development (profiles) | Enriches telemetry with Kubernetes pod/namespace/node/workload metadata, associating each record to a pod by IP or resource attribute. Renamed from k8sattributes in v0.146.0; alias preserved. |
routing |
components/routing/README.md |
connector | traces, metrics, logs | Alpha | Routes same-signal telemetry to different pipelines by OTTL condition/statement per context; ordered table, first match wins, default_pipelines fallback. Replaces the deprecated routingprocessor. |
memory_limiter |
components/memory_limiter/README.md |
processor | traces, metrics, logs, profiles | Beta (traces/metrics/logs), Alpha (profiles) | Safety valve against OOM: refuses data with backpressure when Go heap exceeds a soft/hard limit, forcing GC above the hard limit. Belongs first in every pipeline; pairs with GOMEMLIMIT. |
load_balancing |
components/load_balancing/README.md |
exporter | traces, logs, metrics | Beta (traces/logs), Development (metrics) | Distributes telemetry across downstream Collectors via a consistent-hash ring keyed on trace ID / service.name (etc.), pinning related records to one backend. The standard way to scale tail_sampling/span_metrics. Renamed from loadbalancing in v0.153.0; alias preserved. |
otlp (receiver) |
components/otlp/README.md |
receiver | traces, metrics, logs, profiles | Stable (traces/metrics/logs), Development (profiles) | The canonical OTLP ingress over gRPC (4317) and/or HTTP (4318, protobuf + JSON). protocols: block, at least one required. Default endpoint is localhost, not 0.0.0.0 — must be set explicitly to receive containerized traffic. |
otlp_grpc (exporter) |
components/otlp_exporter/README.md |
exporter | traces, metrics, logs, profiles | Stable (traces/metrics/logs), Development (profiles) | Sends OTLP over gRPC to a downstream endpoint; gzip by default. Built-in sending_queue.batch (flush 200ms / 8192 items) replaces the batch processor, plus retry_on_failure. Renamed from otlp in core v1.50.0; alias preserved. |
file_log (receiver) |
components/file_log/README.md |
receiver | logs | Beta | Tails log files (glob include), turns each line/entry into a log record, and parses it via a stanza operators pipeline (json/regex/severity/timestamp/recombine). Fingerprint + offset tracking across rotation; storage for durable offsets. start_at defaults to end (existing files look empty). Renamed from filelog in v0.149.0; alias preserved. |
resource_detection |
components/resource_detection/README.md |
processor | traces, metrics, logs, profiles | Beta (traces/metrics/logs), Development (profiles) | Auto-detects resource attributes from the Collector's environment (host, cloud metadata services, k8s, OTEL_RESOURCE_ATTRIBUTES) via an ordered detectors list; override governs detected-vs-incoming. A failed detector stops startup. Renamed from resourcedetection in v0.153.0; alias preserved. |
file_storage |
components/file_storage/README.md |
extension | — (not pipeline-scoped) | Beta | Persists component state to local disk (bbolt) so it survives a Collector restart: receiver read offsets (storage:), exporter persistent send queues (sending_queue.storage:), and stateful-processor decision caches. One bbolt file per consumer; directory must exist unless create_directory: true. Not placed in a pipeline — listed under service.extensions: and referenced by other components. |
prometheus (receiver) |
components/prometheus/README.md |
receiver | metrics | Beta | Scrapes Prometheus-format HTTP endpoints and converts them to OTLP metrics, embedding prometheus/prometheus's scrape manager — the config: block is the same YAML as prometheus.yml (global, scrape_configs, scrape_config_files, service discovery, relabeling). Extra keys: trim_metric_suffixes, target_allocator (sharded targets from the OTel Operator), api_server (debug API). Scrape-only: rejects remote_write/remote_read/rule_files/alerting. Stateful, does not auto-shard across replicas. |
prometheus (exporter) |
components/prometheus_exporter/README.md |
exporter | metrics | Beta | Exposes pipeline metrics in Prometheus exposition format on a /metrics HTTP endpoint for a Prometheus server to scrape (pull, not push — contrast prometheusremotewrite). Embeds confighttp.ServerConfig; endpoint required (no default). In-memory accumulator keeps the latest value per series, dropping it after metric_expiration (5m). namespace, const_labels, send_timestamps, resource_to_telemetry_conversion, enable_open_metrics (exemplars), without_scope_info; add_metric_suffixes deprecated in favor of translation_strategy. Same prometheus type string as the receiver, different class. |
prometheus_remote_write (exporter) |
components/prometheus_remote_write/README.md |
exporter | metrics | Beta | Pushes OTLP metrics out as Prometheus Remote Write requests to RW-compatible backends (Cortex, Mimir, Thanos) — the opposite direction of the prometheus exporter. Type renamed prometheusremotewrite→prometheus_remote_write in v0.154.0 (deprecated alias warns). Speaks RW1 by default (protobuf_message; RW2 behind a feature gate, in development). TLS on by default (tls.insecure to disable), snappy-only compression, remote_write_queue (not sending_queue). endpoint required. Drops non-cumulative monotonic sums, histograms, and summaries under RW1. namespace, external_labels, target_info, resource_to_telemetry_conversion, disable_scope_info, add_metric_suffixes/translation_strategy, wal, max_batch_size_bytes, max_batch_request_parallelism. |
Collector-wide conventions
Named instances
Every component type supports the type/name pattern so the same type can be configured more than once. The pipeline references the named form:
processors:
log_dedup/health-checks:
interval: 30s
conditions:
- 'attributes["log.type"] == "health_check"'
log_dedup/access-logs:
interval: 10s
service:
pipelines:
logs/health:
processors: [log_dedup/health-checks]
logs/access:
processors: [log_dedup/access-logs]
Stability levels
Components publish a stability level per signal. Treat these as load-bearing when recommending production use:
| Level | Use in |
|---|---|
| Development | Tests and prototypes only — breaking changes expected. |
| Alpha | Limited, non-critical workloads — config keys can still change. |
| Beta | Production viable — breaking changes rare. |
| Stable | Production — backward compatibility guaranteed. |
Stability now varies per component — and per signal for multi-signal components (e.g. redaction is Beta for traces but Alpha for logs/metrics). Don't assume a single level for the indexed set: check each component's README header metadata table for the authoritative stability and surface it when the user asks about production readiness.
Recent renames
Many components were renamed to snake_case in v0.150.0–v0.151.0. The legacy names remain as deprecated aliases — old configs keep working but new configs should use the new names. Check the upstream component README for the exact rename version before flagging a config as broken.
Examples: logdedup → log_dedup, hostmetrics → host_metrics, spanmetrics → span_metrics, servicegraph → service_graph, k8sattributes → k8s_attributes, plus several _log and _check receivers.
Pipeline placement
Two rules of thumb that apply across components:
memory_limiterbelongs first in any processor list, before anything that allocates buffers (log_dedup,transform,tail_sampling, …).- Batching is now done by the exporter's
sending_queue.batch, not by a separatebatchprocessor. Don't addbatchto new pipelines.
Verification harness
Each component page's Verification section gives a config, a telemetrygen command, and the expected output. To run any of them:
- Save the YAML to a file and start a collector that bundles the component — for components in the
contrib/k8sdistributions,otelcol-contrib --config <file>.yaml; for components not in any distribution, build a custom collector with the OpenTelemetry Collector Builder (OCB) first. - Send telemetry with
telemetrygen(see theotel-telemetrygenskill). - Watch the
debugexporter's stdout (or thefileexporter's output) for the expected result.
The Verification configs are minimal repros: they omit memory_limiter and other production scaffolding on purpose, to isolate the component under test. Don't copy them verbatim into production.
Adding a new component to this skill
When extending coverage:
- Create the directory
components/<type>/. Files carry no frontmatter — onlySKILL.mdhas frontmatter. - Write a lean
README.md— always loaded, kept small:- Header metadata table — kind,
typename, signals, per-signal stability, distributions, Go module, upstream README link, and a rename note if the component was renamed. - Description — what the component does and the mechanism, in 1–2 tight paragraphs (push detailed mechanism/reference into
configuration.md). - Main use-cases — "Use when" / "Avoid when".
- Related components — cross-links.
- Details index — a bullet list where each item links a detail file followed by an em dash and a short description of its contents (e.g.
- [Configuration](configuration.md) — config keys, defaults, validation), so the reader loads only what a question needs.
- Header metadata table — kind,
- Split the rest into on-demand detail files under the same directory:
configuration.md— full config-reference table (key, type, default, validation) plus any mechanism/reference tables.verification.md— atelemetrygen+debug/fileexporter recipe that proves the documented behavior; cross-reference theotel-telemetrygenskill. Verify everytelemetrygenflag against that skill — never assert a flag that doesn't exist. Iftelemetrygencan't produce the input the component needs, say so and point to an alternative (OTTL/transform, a custom emitter). Keep the config a minimal repro (see Verification harness).advanced.md— named instances, multi-pipeline setups, combinations, and edge configs.quirks.md— gotchas, stability caveats, memory model, a validation-error→fix table, anti-patterns, and troubleshooting.- Split a heavy section into its own file when it's large (e.g.
policies.mdfor a big policy catalog); merge trivial sections into a sibling rather than create a stub. Repoint any in-page anchor links that now cross files.
- Use
components/log_dedup/andcomponents/interval/as reference implementations of this structure. - Add a row to the Component index above (the
Filecolumn points atcomponents/<type>/README.md). - Update the description trigger phrases in this file's frontmatter if the new component introduces a clearly distinct user-facing keyword.