**License: Enterprise** - Requires an Enterprise license.

**Online mode only** - This probe requires an active connection to the SenHub Observability Platform. It is not available in offline mode.

OpenTelemetry Probe#

Introduction#

The OpenTelemetry probe is a SenHub Agent component that receives telemetry data (metrics, traces, logs) from applications instrumented with OpenTelemetry. It supports both HTTP and gRPC protocols for data collection, providing maximum flexibility for integration into different architectures.

Key Features#

• OTLP (OpenTelemetry Protocol) data reception
• HTTP and gRPC protocol support
• Simultaneous collection of metrics, traces, and logs
• Flexible endpoint and authentication configuration
• TLS support for secure communications
• Seamless integration with the SenHub metrics system

Probe Configuration#

Basic Configuration#

Here is a basic configuration example for the OpenTelemetry probe in the SenHub Agent configuration file:

probes:
  - name: otel
    type: otel
    interval: 60  # collection interval in seconds
    telemetry_types:
      - metrics
      - traces
      - logs

HTTP Collector Configuration#

probes:
  - name: otel
    type: otel
    interval: 60
    http:
      endpoint: "http://localhost:4318"
      timeout: 30  # timeout in seconds
      headers:
        Content-Type: "application/json"
        Authorization: "Bearer <token>"
      telemetry_types:
        - metrics
        - logs

gRPC Collector Configuration#

probes:
  - name: otel
    type: otel
    interval: 60
    grpc:
      endpoint: "localhost:4317"
      timeout: 30  # timeout in seconds
      insecure: false  # use secure TLS connection (true to disable TLS)
      telemetry_types:
        - metrics
        - traces

Advanced Configuration (HTTP and gRPC in Parallel)#

probes:
  - name: otel
    type: otel
    interval: 60
    telemetry_types:
      - metrics
      - traces
      - logs
    http:
      endpoint: "http://localhost:4318"
      timeout: 30
      telemetry_types:
        - metrics
        - logs
    grpc:
      endpoint: "localhost:4317"
      timeout: 30
      insecure: false
      telemetry_types:
        - traces

Collected Metrics#

The OpenTelemetry probe is a passive receiver: it does not emit its own fixed metric set. Instead, it forwards every metric, trace, and log that a client pushes via OTLP. The set of metrics you see in the SenHub back-end depends entirely on how your applications are instrumented.

Probe Operational Metrics#

In addition to pass-through data, the probe emits operational metrics so you can observe its own health:

Supported OTLP Metric Types#

• Counters — Monotonically increasing values (forwarded as counter)
• Gauges — Point-in-time observations (forwarded as gauge)
• Histograms — Value distributions with buckets (forwarded as histogram)
• UpDown Counters — Counters that can increase and decrease (forwarded as gauge)

Resource attributes (service.name, service.version, host.name, …) are preserved as tags so metrics remain filterable per-service and per-host downstream.

Example Received Metrics#

Name: http.server.request.duration
Type: Histogram
Tags:
  - host: web-server-01
  - method: GET
  - route: /api/users
  - status_code: 200

Name: system.memory.usage
Type: Gauge
Tags:
  - host: app-server-02
  - state: used

Security#

TLS Configuration#

For gRPC connections, TLS security is enabled by default. You can configure TLS parameters as follows:

probes:
  - name: otel
    type: otel
    grpc:
      endpoint: "localhost:4317"
      insecure: false  # true to disable TLS
      ca_file: "/path/to/ca.pem"  # optional - custom CA certificate
      cert_file: "/path/to/cert.pem"  # optional - client certificate
      key_file: "/path/to/key.pem"  # optional - client private key

Authentication#

Several authentication methods are supported:

Basic Auth (HTTP)#

probes:
  - name: otel
    type: otel
    http:
      endpoint: "http://localhost:4318"
      username: "user"
      password: "pass"

Token Authentication (HTTP & gRPC)#

For HTTP:

probes:
  - name: otel
    type: otel
    http:
      endpoint: "http://localhost:4318"
      headers:
        Authorization: "Bearer eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9..."

For gRPC:

probes:
  - name: otel
    type: otel
    grpc:
      endpoint: "localhost:4317"
      token: "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9..."

Troubleshooting#

Common Issues and Solutions#

1. Connection refused

   • Verify that the OTLP endpoint is correctly configured and active
   • Check that the port is open and accessible
   • Test the connection with telnet <host> <port> to verify reachability

2. Authentication errors

   • Verify that the credentials are correct
   • Ensure that authentication headers are properly configured
   • Check that the token has not expired

3. TLS errors

   • Verify that certificates are valid and not expired
   • Ensure the hostname matches the name in the certificate
   • Check that CA, cert, and key file paths are correct

4. No data received

   • Verify that telemetry types (metrics, traces, logs) are correctly configured
   • Check that the source application is actually sending data
   • Increase the logging level for more details

Logging and Diagnostics#

To enable detailed logging for the OpenTelemetry probe, add the following configuration:

logging:
  level: debug
  probes:
    otel: trace  # specific log level for the OpenTelemetry probe

Configuration Validation#

Use the following command to validate the probe configuration:

senhub-agent validate --config path/to/config.yaml

Usage Examples#

Collecting Metrics from a Web Application#

probes:
  - name: otel
    type: otel
    interval: 30
    telemetry_types:
      - metrics
    http:
      endpoint: "http://webapp:4318"
      timeout: 15

Collecting Traces from a Microservices Architecture#

probes:
  - name: otel
    type: otel
    interval: 60
    telemetry_types:
      - traces
    grpc:
      endpoint: "tracing-service:4317"
      timeout: 30
      insecure: false
      token: "${OTEL_AUTH_TOKEN}"  # using an environment variable

Full Collection for a Production Environment#

probes:
  - name: otel
    type: otel
    interval: 60
    telemetry_types:
      - metrics
      - traces
      - logs
    http:
      endpoint: "https://otel-collector.example.com:4318"
      timeout: 30
      headers:
        Authorization: "Bearer ${OTEL_TOKEN}"
      verify_ssl: true
    retry:
      max_attempts: 3
      initial_delay: 5
      max_delay: 30
      multiplier: 2