Export to Your Observability Backend

Mermin exports Flow Traces via the OpenTelemetry Protocol (OTLP), compatible with any OTLP-enabled observability backend or collector.

What You Need

To receive Flow Traces from Mermin, you need one of:

1. OTLP-Enabled Collector: OpenTelemetry Collector that receives OTLP and forwards to your backend(s)

2. OTLP Data Platform: An observability platform with native OTLP ingestion

OpenTelemetry Collector (Recommended)

The OpenTelemetry Collector provides the most flexibility:

• Receives OTLP from Mermin via gRPC or HTTP

• Processes, batches, and transforms telemetry data

• Exports to multiple backends simultaneously

• Provides buffering and retry logic

Example Configuration: See Mermin with OpenTelemetry Collector for a complete setup with OpenTelemetry Collector, including Mermin configuration and collector pipeline.

Basic Mermin Configuration

export "traces" {
  otlp = {
    endpoint = "http://otel-collector:4317"  # Collector's OTLP gRPC endpoint
    protocol = "grpc" # Optional; Mermin defaults to "grpc".
  }
}

OTLP-Compatible Data Platforms

Flow Traces work with any platform supporting OTLP trace ingestion:

Elastic Stack

Elasticsearch with APM Server or OpenTelemetry Collector ingests OTLP traces.

Use Case: Full-text search, complex aggregations, APM integration, machine learning

How to Connect:

• Point Mermin → OpenTelemetry Collector → Elasticsearch exporter

• Or point Mermin → Elastic APM Server (OTLP endpoint)

Example: See docs/deployment/examples/netobserv-os-simple-svc/ for OpenSearch (Elastic-compatible) deployment

OpenSearch

Open-source alternative to Elasticsearch with native OTLP support via OpenTelemetry Collector.

Use Case: Open-source search and analytics, cost-effective storage

Examples:

• docs/deployment/examples/netobserv-os-simple-svc/ - Basic OpenSearch setup

• docs/deployment/examples/netobserv-os-simple-gke-gw/ - GKE deployment with Gateway API

Greptime Ingestion

Greptime is a database designed for high-cardinality time series data that supports OTLP ingestion.

export "traces" {
  otlp = {
    endpoint = "http://greptime-standalone-instance:4000/v1/otlp/v1/traces"
    protocol = "http_binary"

    headers = {
      "x-greptime-db-name"       = "public"
      "x-greptime-pipeline-name" = "greptime_trace_v1"
    }
  }
}

Example: docs/deployment/examples/greptime_simple_svc

Grafana Cloud, Datadog, New Relic, Honeycomb, etc

Most commercial observability platforms support OTLP ingestion.

How to Connect:

1. Obtain your platform's OTLP endpoint URL

2. Configure authentication (usually API key or bearer token)

3. Point Mermin to the endpoint with auth

export "traces" {
  otlp = {
    endpoint = "https://otlp.provider.com:4317"
    headers = {
      "authorization" = "Bearer ${API_TOKEN}"
    }
  }
}

Examples: Coming soon...

Flow Trace Data Model

Each Flow Trace is an OpenTelemetry span containing:

Span Attributes:

• Network 5-tuple: source/dest IPs, ports, protocol

• Bidirectional counters: bytes sent/received, packets sent/received

• TCP state: flags (SYN, FIN, RST), connection state

• Kubernetes metadata: pod, service, deployment, namespace, labels

• Community ID for flow correlation across monitoring points

Resource Attributes:

• Kubernetes cluster name

• Node name

• Mermin version

Query Flow Traces using native backend query languages (TraceQL, KQL, Lucene).

Testing with Stdout

For local development and testing, output Flow Traces to stdout instead of OTLP:

export "traces" {
  stdout = {
    format = "text_indent"  # Human-readable format
  }
}

View traces in Mermin logs:

kubectl logs -f -l app.kubernetes.io/name=mermin

Next Steps

Configure Export

1. Configure OTLP Export: Set up endpoints, authentication, and TLS

2. Review Example Configurations: Complete deployment examples with backends

Optimize

Need Help?

• Troubleshoot Export Issues: Diagnose connection and authentication problems

• GitHub Discussions: Share your backend setup and get community advice