OpenTelemetry Protocol (OTLP)

Network

Synopsis

Creates a target that forwards telemetry data to any OpenTelemetry Protocol (OTLP)-compatible receiver. Supports HTTP and gRPC transports, protobuf and JSON encoding, gzip compression, custom headers, TLS, and configurable retry logic.

note

This target has no GUI creation wizard. Configure it directly in the target YAML file.

Schema

- name: <string>
  description: <string>
  type: otlp
  pipelines: <pipeline[]>
  status: <boolean>
  properties:
    url: <string>
    address: <string>
    port: <numeric>
    protocol: <string>
    path: <string>
    format: <string>
    compression: <boolean>
    timeout: <numeric>
    batch_size: <numeric>
    max_retries: <numeric>
    retry_delay: <numeric>
    grpc_passthrough: <boolean>
    headers:
      <key>: <value>
    tls:
      status: <boolean>
      verify: <boolean>
      cert_name: <string>
      key_name: <string>
      server_name: <string>
      min_tls_version: <string>
    debug:
      status: <boolean>
      dont_send_logs: <boolean>

Configuration

The following fields are used to define the target:

Field	Required	Default	Description
`name`	Y		Target name
`description`	N	-	Optional description
`type`	Y		Must be `otlp`
`pipelines`	N	-	Optional post-processor pipelines
`status`	N	`true`	Enable/disable the target

Connection

Field	Required	Default	Description
`url`	Y*	-	Full endpoint URL for HTTP (e.g. `http://collector:4318`) or `host:port` for gRPC
`address`	Y*	-	Remote host; alternative to `url`
`port`	Y*	-	Remote port; alternative to `url`

* = Provide url or both address and port. Exactly one form is required.

Transport

Field	Required	Default	Description
`protocol`	N	`http`	Wire transport: `http` or `grpc`
`path`	N	`/v1/logs`	HTTP URL path; leading `/` is added automatically. Use `/v1/metrics` or `/v1/traces` for other signals. HTTP only.
`format`	N	`protobuf`	Encoding: `protobuf` or `json`. `json` is invalid with `protocol: grpc`.
`compression`	N	`true`	Enable gzip compression

Performance

Field	Required	Default	Description
`timeout`	N	`30`	Request or RPC timeout in seconds
`batch_size`	N	`1000`	Maximum events per batch; must be >= 1
`max_retries`	N	`3`	Maximum delivery attempts on failure; must be >= 0
`retry_delay`	N	`1`	Seconds between retry attempts

gRPC

Field	Required	Default	Description
`grpc_passthrough`	N	`true`	When `true`, sends raw OTLP bytes using `content-subtype: raw-otlp` (VirtualMetric-to-VirtualMetric only). When `false`, re-encodes as standard typed OTLP/gRPC for interoperability with any spec-compliant receiver.

Headers

Field	Required	Default	Description
`headers`	N	-	Map of string key-value pairs added to every HTTP request or gRPC metadata (e.g. authorization tokens, tenant IDs)

TLS

Field	Required	Default	Description
`tls.status`	N	`false`	Enable TLS
`tls.verify`	N	`true`	Verify server certificate
`tls.cert_name`	N*	-	Client certificate file name (PEM format)
`tls.key_name`	N*	-	Client private key file name (PEM format)
`tls.server_name`	N	-	SNI override / ServerName for TLS handshake
`tls.min_tls_version`	N	`tls1.2`	Minimum TLS version: `tls1.0`, `tls1.1`, `tls1.2`, `tls1.3`

* = tls.cert_name and tls.key_name must be provided together or omitted together.

Scheduling

See Scheduling and Pool Behavior for interval and cron fields shared by all targets.

Debug Options

Field	Required	Default	Description
`debug.status`	N	`false`	Enable debug logging
`debug.dont_send_logs`	N	`false`	Process logs but don't send to target (testing)

Details

The OTLP target delivers telemetry to any OpenTelemetry-compatible receiver — otel-collector, rotel, Grafana Alloy, vendor ingest endpoints, or another VirtualMetric Director.

Record translation

Records originating from this Director's own OTEL listener carry a JSON envelope with full Resource and Scope context. The target parses the envelope and reassembles each record as a one-record ExportLogsServiceRequest, preserving the original Resource and Scope end-to-end. This path is lossless.

Records from non-OTEL sources (TCP listener, syslog, etc.) are wrapped as a synthetic LogRecord with the body set to the raw message bytes and minimal resource attributes (service.name = the device name). This path is lossy by definition — non-OTEL sources have no OTLP context — but produces valid OTLP that any downstream collector accepts.

HTTP transport

HTTP is the default transport. Each worker maintains its own http.Client to avoid idle-connection contention. Batches are POSTed to endpoint + path. The Content-Type header is set to application/x-protobuf for format: protobuf and application/json for format: json. When compression: true, the body is gzip-compressed and Content-Encoding: gzip is set.

The path field controls the signal type delivered: /v1/logs (default), /v1/metrics, or /v1/traces. The wire payload for all three is the corresponding OTLP proto message — only the path and embedded message type differ.

gRPC transport

When protocol: grpc, each worker maintains its own grpc.ClientConn. The gRPC method path is fixed to /opentelemetry.proto.collector.logs.v1.LogsService/Export (logs only in v1; metrics and traces require the HTTP path via path).

grpc_passthrough: true (default): sends raw OTLP bytes using grpcraw.Codec with content-subtype: raw-otlp. This is the fast path for VirtualMetric-to-VirtualMetric relay — one Director to another with no re-serialization. Standard OTLP/gRPC receivers (otel-collector, rotel, vendor gateways) reject this subtype as Unimplemented.

grpc_passthrough: false: re-encodes each batch into the typed proto message (ExportLogsServiceRequest, etc.) using the standard gRPC codec and marshals with UnmarshalVT. This produces spec-compliant OTLP/gRPC that any receiver accepts, at the cost of one additional unmarshal+marshal per outbound batch. Use false for cross-vendor deployments.

Configuration validation

The following rules are enforced at config load:

url or (address + port) must be provided; providing neither is rejected.
format must be protobuf or json.
format: json combined with protocol: grpc is rejected — OTLP/gRPC is protobuf-only on the wire.
batch_size must be >= 1.
max_retries must be >= 0.
tls.cert_name and tls.key_name must both be present or both be absent.

Examples

Basic HTTP

Forwarding logs to an OTLP/HTTP collector with default settings...

targets:
  - name: otel_collector
    type: otlp
    properties:
      url: "http://otel-collector.example.com:4318"

JSON Format over HTTP

Sending telemetry as JSON-encoded OTLP to an HTTP endpoint...

targets:
  - name: otel_json
    type: otlp
    properties:
      url: "http://otel-collector.example.com:4318"
      format: json
      path: /v1/logs

gRPC Spec-Compliant

Delivering logs over gRPC to a third-party collector using typed OTLP encoding...

targets:
  - name: grpc_collector
    type: otlp
    properties:
      address: "otel-collector.example.com"
      port: 4317
      protocol: grpc
      grpc_passthrough: false

TLS-Secured

Sending logs over HTTPS with mutual TLS client certificate authentication...

targets:
  - name: otel_secure
    type: otlp
    properties:
      url: "https://otel-collector.example.com:4318"
      tls:
        status: true
        verify: true
        cert_name: "client-cert.pem"
        key_name: "client-key.pem"
        min_tls_version: "tls1.2"

Performance Tuning

High-volume configuration with large batches, retry logic, and auth header...

targets:
  - name: otel_high_volume
    type: otlp
    properties:
      url: "https://ingest.example.com:4318"
      format: protobuf
      compression: true
      batch_size: 5000
      timeout: 60
      max_retries: 5
      retry_delay: 2
      headers:
        Authorization: "Bearer ${OTLP_TOKEN}"
        X-Tenant-ID: "tenant-prod"

Synopsis​

Schema​

Configuration​

Connection​

Transport​

Performance​

gRPC​

Headers​

TLS​

Scheduling​

Debug Options​

Details​

Record translation​

HTTP transport​

gRPC transport​

Configuration validation​

Examples​

Basic HTTP​

JSON Format over HTTP​

gRPC Spec-Compliant​

TLS-Secured​

Performance Tuning​