Logging Configuration

Configure Traefik logs with multiple formats, rotation policies, and OpenTelemetry integration for comprehensive system monitoring.

Logging Configuration

Traefik logs capture all operational events including startup, configuration changes, errors, and system warnings. By default, logs are written to stdout in text format.

Basic Configuration

Logs are enabled by default. Configure log level and format:

YAML

log:
  level: DEBUG
  format: json
  filePath: /var/log/traefik/traefik.log

Configuration Options

Log Level

level · string · default: "ERROR"

Set the logging level to control verbosity.

Available log levels (in order of verbosity):

• TRACE - Most verbose, includes all debug information
• DEBUG - Detailed debugging information
• INFO - General informational messages
• WARN - Warning messages
• ERROR - Error messages (default)
• FATAL - Fatal errors that cause termination
• PANIC - Panic-level errors

YAML

log:
  level: DEBUG

File Path

filePath · string · default: "stdout"

Path to the log file. If not specified, logs are written to stdout.

When filePath is specified, Traefik writes logs only to the file (not to stdout). Intermediate directories are created automatically.

YAML

log:
  filePath: /var/log/traefik/traefik.log

Format

format · string · default: "common"

Log output format: common (text) or json.

Common (Text)

Human-readable text format with optional colors:

log:
  format: common

Example output:

time="2026-03-03T10:00:00Z" level=info msg="Configuration loaded"

JSON

Structured JSON format for log aggregation:

log:
  format: json

Example output:

{"level":"info","msg":"Configuration loaded","time":"2026-03-03T10:00:00Z"}

Disable Colors

noColor · boolean · default: "false"

Disable colorized output when using the common format.

YAML

log:
  format: common
  noColor: true

Log Rotation

Configure automatic log rotation to prevent disk space issues:

Max Size

maxSize · integer · default: "100"

Maximum size in megabytes before rotation.

YAML

log:
  filePath: /var/log/traefik/traefik.log
  maxSize: 50

Max Backups

maxBackups · integer · default: "unlimited"

Maximum number of old log files to retain.

YAML

log:
  maxBackups: 7

Max Age

maxAge · integer · default: "unlimited"

Maximum number of days to retain old log files.

YAML

log:
  maxAge: 30

Compression

compress · boolean · default: "false"

Compress rotated log files using gzip.

YAML

log:
  compress: true

Complete Rotation Example

YAML

log:
  filePath: /var/log/traefik/traefik.log
  maxSize: 100
  maxBackups: 3
  maxAge: 7
  compress: true

OpenTelemetry Logs

Experimental Feature

OpenTelemetry logs are currently experimental and must be explicitly enabled.

Enable Experimental Feature

YAML

experimental:
  otlpLogs: true

log:
  otlp: {}

Default protocol is HTTPS to https://localhost:4318/v1/logs.

Service Name

otlp.serviceName · string · default: "traefik"

Service name resource attribute for OTLP logs.

YAML

log:
  otlp:
    serviceName: traefik-prod

Resource Attributes

otlp.resourceAttributes · object · default: "{}"

Additional resource attributes sent to the collector.

YAML

log:
  otlp:
    resourceAttributes:
      environment: production
      datacenter: us-east-1

HTTP Configuration

Send logs via HTTP to the OpenTelemetry Collector:

YAML

log:
  otlp:
    http:
      endpoint: https://otel-collector:4318/v1/logs
      headers:
        Authorization: Bearer token123
      tls:
        ca: /path/to/ca.crt
        cert: /path/to/client.cert
        key: /path/to/client.key

To disable TLS, use http:// instead of https:// in the endpoint URL.

gRPC Configuration

Send logs via gRPC to the OpenTelemetry Collector:

YAML

log:
  otlp:
    grpc:
      endpoint: otel-collector:4317
      insecure: false
      headers:
        Authorization: Bearer token123
      tls:
        ca: /path/to/ca.crt

Complete Examples

Production Logging Setup

YAML

log:
  level: INFO
  format: json
  filePath: /var/log/traefik/traefik.log
  maxSize: 100
  maxBackups: 5
  maxAge: 30
  compress: true

Development Setup

YAML

log:
  level: DEBUG
  format: common

OpenTelemetry Integration

YAML

experimental:
  otlpLogs: true

log:
  level: INFO
  format: json
  otlp:
    serviceName: traefik-prod
    resourceAttributes:
      environment: production
      cluster: us-east
    http:
      endpoint: https://otel-collector:4318/v1/logs
      headers:
        X-API-Key: secret

External Log Rotation

On Linux/Unix systems, you can use logrotate for external log rotation. Traefik responds to USR1 signals to reopen log files:

kill -USR1 <traefik-pid>

Windows Support

USR1 signal rotation is not supported on Windows.