Log Architecture & Structural Overview

The Traefik Ingress Router Access Log Parser is an essential telemetry stream within the Web Servers & Reverse Proxies ecosystem. Parse Traefik Cloud Native proxy access logs with router names, service backends, and round-trip duration.

This schema defines a structure of 14 extracted attributes, including 4 numeric metrics and 10 string dimensions. In production observability architectures, these tokens provide high-cardinality indexing keys for telemetry pipelines before shipping to storage backends such as ClickHouse, Elasticsearch, Amazon S3, or Datadog.

Raw Telemetry Ingestion Profile

A typical raw event line for traefik-access-log averages 150 bytes across 14 tokens. Modern collectors such as Fluent Bit and Vector require zero-backtracking regular expressions to avoid CPU spikes during traffic surges.

Extracted Field Schema & Data Types

The transpiled Grok pattern extracts the following schema fields from each raw event line. Data collectors cast these values according to the typed mappings below.

Field Name	Inferred Type	Description & Collector Semantics
client_ip	string	Client IP address.
auth	string	Authenticated user or '-'.
timestamp	string	HTTPDATE timestamp.
method	string	HTTP method.
path	string	Path requested.
http_version	string	HTTP protocol version.
status	integer	HTTP status.
bytes	integer	Bytes transferred.
referrer	string	Referrer URL.
user_agent	string	User agent.
request_count	integer	Sequential request counter on connection.
router_name	string	Matched Traefik router name.
service_url	string	Matched backend service destination.
duration_ms	integer	Duration in milliseconds.

Common Regex Traps & Production Edge Cases

Engineers frequently encounter ingestion failures or pipeline drops due to subtle variations in real-world event logs. Watch out for these verified pitfalls:

1Traefik appends 'ms' directly to duration; ensure your pattern captures the integer before the 'ms' suffix.

2Internal router matches show service_url as '-'.

Production Collector Setup & Configurations

Pre-configured parser definitions ready to be dropped into your infrastructure repository.

Fluent Bit (parsers.conf)

Format: regex

# ==============================================================================
# Fluent Bit Parser Configuration (parsers.conf)
# ==============================================================================
[PARSER]
    Name        logpipeline_parser
    Format      regex
    Regex       ^(?<client_ip>(?:(?:(?:(?:(?:(?:[0-9A-Fa-f]{1,4}:){7}[0-9A-Fa-f]{1,4}|(?:[0-9A-Fa-f]{1,4}:){1,7}:|(?:[0-9A-Fa-f]{1,4}:){1,6}:[0-9A-Fa-f]{1,4}|(?:[0-9A-Fa-f]{1,4}:){1,5}(?::[0-9A-Fa-f]{1,4}){1,2}|(?:[0-9A-Fa-f]{1,4}:){1,4}(?::[0-9A-Fa-f]{1,4}){1,3}|(?:[0-9A-Fa-f]{1,4}:){1,3}(?::[0-9A-Fa-f]{1,4}){1,4}|(?:[0-9A-Fa-f]{1,4}:){1,2}(?::[0-9A-Fa-f]{1,4}){1,5}|[0-9A-Fa-f]{1,4}:(?:(?::[0-9A-Fa-f]{1,4}){1,6})|:(?:(?::[0-9A-Fa-f]{1,4}){1,7}|:)|fe80:(?::[0-9A-Fa-f]{0,4}){0,4}%[0-9a-zA-Z]+|::(?:ffff(?::0{1,4})?:)?(?:(?:25[0-5]|(?:2[0-4]|1?[0-9])?[0-9])\.){3}(?:25[0-5]|(?:2[0-4]|1?[0-9])?[0-9])|(?:[0-9A-Fa-f]{1,4}:){1,4}:(?:(?:25[0-5]|(?:2[0-4]|1?[0-9])?[0-9])\.){3}(?:25[0-5]|(?:2[0-4]|1?[0-9])?[0-9])))|(?:(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?))))|(?:\b(?:[0-9A-Za-z][0-9A-Za-z-]{0,62})(?:\.(?:[0-9A-Za-z][0-9A-Za-z-]{0,62}))*(?:\.?|\b)))) - (?<auth>(?:[a-zA-Z0-9._-]+)) \[(?<timestamp>(?:(?:(?:0[1-9])|(?:[12][0-9])|(?:3[01])|[1-9]))/(?:\b(?:Jan(?:uary)?|Feb(?:ruary)?|Mar(?:ch)?|Apr(?:il)?|May|Jun(?:e)?|Jul(?:y)?|Aug(?:ust)?|Sep(?:tember)?|Oct(?:ober)?|Nov(?:ember)?|Dec(?:ember)?)\b)/(?:\b[0-9]{4}\b):(?:(?:(?:(?:2[0123]|[01]?[0-9])):(?:(?:[0-5][0-9]))(?::(?:(?:(?:[0-5]?[0-9]|60)(?:[:.,][0-9]+)?))))) (?:(?:Z|[+-](?:(?:2[0123]|[01]?[0-9]))(?::?(?:(?:[0-5][0-9]))))))\] "(?<method>\b\w+\b) (?<path>\S+) HTTP/(?<http_version>(?:(?:(?:[+-]?(?:[0-9]+(?:\.[0-9]+)?|\.[0-9]+)))))" (?<status>(?:[+-]?(?:[0-9]+))) (?<bytes>(?:[+-]?(?:[0-9]+))) "(?<referrer>.*?)" "(?<user_agent>.*?)" (?<request_count>(?:[+-]?(?:[0-9]+))) "(?<router_name>.*?)" "(?<service_url>.*?)" (?<duration_ms>(?:[+-]?(?:[0-9]+)))ms$
    Time_Key    timestamp
    Time_Format %Y-%m-%dT%H:%M:%S%z
    Types       status:integer bytes:integer request_count:integer duration_ms:integer

# ==============================================================================
# Fluent Bit Pipeline Filter (fluent-bit.conf)
# ==============================================================================
[FILTER]
    Name         parser
    Match        *
    Key_Name     log
    Parser       logpipeline_parser
    Reserve_Data On

Vector.dev (Remap VRL)

parse_regex!

# ==============================================================================
# Vector.dev Remap Language (VRL) Transform
# Use inside a 'remap' transform in vector.yaml
# ==============================================================================
.parsed, err = parse_regex(.message, r'^(?<client_ip>(?:(?:(?:(?:(?:(?:[0-9A-Fa-f]{1,4}:){7}[0-9A-Fa-f]{1,4}|(?:[0-9A-Fa-f]{1,4}:){1,7}:|(?:[0-9A-Fa-f]{1,4}:){1,6}:[0-9A-Fa-f]{1,4}|(?:[0-9A-Fa-f]{1,4}:){1,5}(?::[0-9A-Fa-f]{1,4}){1,2}|(?:[0-9A-Fa-f]{1,4}:){1,4}(?::[0-9A-Fa-f]{1,4}){1,3}|(?:[0-9A-Fa-f]{1,4}:){1,3}(?::[0-9A-Fa-f]{1,4}){1,4}|(?:[0-9A-Fa-f]{1,4}:){1,2}(?::[0-9A-Fa-f]{1,4}){1,5}|[0-9A-Fa-f]{1,4}:(?:(?::[0-9A-Fa-f]{1,4}){1,6})|:(?:(?::[0-9A-Fa-f]{1,4}){1,7}|:)|fe80:(?::[0-9A-Fa-f]{0,4}){0,4}%[0-9a-zA-Z]+|::(?:ffff(?::0{1,4})?:)?(?:(?:25[0-5]|(?:2[0-4]|1?[0-9])?[0-9])\.){3}(?:25[0-5]|(?:2[0-4]|1?[0-9])?[0-9])|(?:[0-9A-Fa-f]{1,4}:){1,4}:(?:(?:25[0-5]|(?:2[0-4]|1?[0-9])?[0-9])\.){3}(?:25[0-5]|(?:2[0-4]|1?[0-9])?[0-9])))|(?:(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?))))|(?:\b(?:[0-9A-Za-z][0-9A-Za-z-]{0,62})(?:\.(?:[0-9A-Za-z][0-9A-Za-z-]{0,62}))*(?:\.?|\b)))) - (?<auth>(?:[a-zA-Z0-9._-]+)) \[(?<timestamp>(?:(?:(?:0[1-9])|(?:[12][0-9])|(?:3[01])|[1-9]))/(?:\b(?:Jan(?:uary)?|Feb(?:ruary)?|Mar(?:ch)?|Apr(?:il)?|May|Jun(?:e)?|Jul(?:y)?|Aug(?:ust)?|Sep(?:tember)?|Oct(?:ober)?|Nov(?:ember)?|Dec(?:ember)?)\b)/(?:\b[0-9]{4}\b):(?:(?:(?:(?:2[0123]|[01]?[0-9])):(?:(?:[0-5][0-9]))(?::(?:(?:(?:[0-5]?[0-9]|60)(?:[:.,][0-9]+)?))))) (?:(?:Z|[+-](?:(?:2[0123]|[01]?[0-9]))(?::?(?:(?:[0-5][0-9]))))))\] "(?<method>\b\w+\b) (?<path>\S+) HTTP/(?<http_version>(?:(?:(?:[+-]?(?:[0-9]+(?:\.[0-9]+)?|\.[0-9]+)))))" (?<status>(?:[+-]?(?:[0-9]+))) (?<bytes>(?:[+-]?(?:[0-9]+))) "(?<referrer>.*?)" "(?<user_agent>.*?)" (?<request_count>(?:[+-]?(?:[0-9]+))) "(?<router_name>.*?)" "(?<service_url>.*?)" (?<duration_ms>(?:[+-]?(?:[0-9]+)))ms$')

if err == null {
    . = merge(., .parsed)
    del(.parsed)

    # Type coercions
    .status = to_int!(.status)
    .bytes = to_int!(.bytes)
    .request_count = to_int!(.request_count)
    .duration_ms = to_int!(.duration_ms)

} else {
    log("LogPipeline parsing warning: " + err, level: "warn")
}

# ==============================================================================
# vector.yaml Pipeline Component
# ==============================================================================
transforms:
  parse_logs:
    type: remap
    inputs: ["source_logs"]
    source: |
      .parsed, err = parse_regex(.message, r'^(?<client_ip>(?:(?:(?:(?:(?:(?:[0-9A-Fa-f]{1,4}:){7}[0-9A-Fa-f]{1,4}|(?:[0-9A-Fa-f]{1,4}:){1,7}:|(?:[0-9A-Fa-f]{1,4}:){1,6}:[0-9A-Fa-f]{1,4}|(?:[0-9A-Fa-f]{1,4}:){1,5}(?::[0-9A-Fa-f]{1,4}){1,2}|(?:[0-9A-Fa-f]{1,4}:){1,4}(?::[0-9A-Fa-f]{1,4}){1,3}|(?:[0-9A-Fa-f]{1,4}:){1,3}(?::[0-9A-Fa-f]{1,4}){1,4}|(?:[0-9A-Fa-f]{1,4}:){1,2}(?::[0-9A-Fa-f]{1,4}){1,5}|[0-9A-Fa-f]{1,4}:(?:(?::[0-9A-Fa-f]{1,4}){1,6})|:(?:(?::[0-9A-Fa-f]{1,4}){1,7}|:)|fe80:(?::[0-9A-Fa-f]{0,4}){0,4}%[0-9a-zA-Z]+|::(?:ffff(?::0{1,4})?:)?(?:(?:25[0-5]|(?:2[0-4]|1?[0-9])?[0-9])\.){3}(?:25[0-5]|(?:2[0-4]|1?[0-9])?[0-9])|(?:[0-9A-Fa-f]{1,4}:){1,4}:(?:(?:25[0-5]|(?:2[0-4]|1?[0-9])?[0-9])\.){3}(?:25[0-5]|(?:2[0-4]|1?[0-9])?[0-9])))|(?:(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?))))|(?:\b(?:[0-9A-Za-z][0-9A-Za-z-]{0,62})(?:\.(?:[0-9A-Za-z][0-9A-Za-z-]{0,62}))*(?:\.?|\b)))) - (?<auth>(?:[a-zA-Z0-9._-]+)) \[(?<timestamp>(?:(?:(?:0[1-9])|(?:[12][0-9])|(?:3[01])|[1-9]))/(?:\b(?:Jan(?:uary)?|Feb(?:ruary)?|Mar(?:ch)?|Apr(?:il)?|May|Jun(?:e)?|Jul(?:y)?|Aug(?:ust)?|Sep(?:tember)?|Oct(?:ober)?|Nov(?:ember)?|Dec(?:ember)?)\b)/(?:\b[0-9]{4}\b):(?:(?:(?:(?:2[0123]|[01]?[0-9])):(?:(?:[0-5][0-9]))(?::(?:(?:(?:[0-5]?[0-9]|60)(?:[:.,][0-9]+)?))))) (?:(?:Z|[+-](?:(?:2[0123]|[01]?[0-9]))(?::?(?:(?:[0-5][0-9]))))))\] "(?<method>\b\w+\b) (?<path>\S+) HTTP/(?<http_version>(?:(?:(?:[+-]?(?:[0-9]+(?:\.[0-9]+)?|\.[0-9]+)))))" (?<status>(?:[+-]?(?:[0-9]+))) (?<bytes>(?:[+-]?(?:[0-9]+))) "(?<referrer>.*?)" "(?<user_agent>.*?)" (?<request_count>(?:[+-]?(?:[0-9]+))) "(?<router_name>.*?)" "(?<service_url>.*?)" (?<duration_ms>(?:[+-]?(?:[0-9]+)))ms$')
      if err == null {
        . = merge(., .parsed)
        del(.parsed)
      }

Datadog Log Pipeline Grok Parser

match_rules

# ==============================================================================
# Datadog Log Processing Pipeline Grok Parser
# Navigate to: Logs -> Configuration -> Pipelines -> Add Processor -> Grok Parser
# ==============================================================================

# Match Rule:
rule %{IPORHOST:client_ip} - %{USER:auth} \[%{HTTPDATE:timestamp}\] "%{WORD:method} %{NOTSPACE:path} HTTP/%{NUMBER:http_version}" %{INT:status} %{INT:bytes} "%{DATA:referrer}" "%{DATA:user_agent}" %{INT:request_count} "%{DATA:router_name}" "%{DATA:service_url}" %{INT:duration_ms}ms

# Complete Datadog Pipeline Processor JSON:
{
  "type": "grok-parser",
  "name": "LogPipeline Grok Parser",
  "is_enabled": true,
  "source": "message",
  "samples": [],
  "grok": {
    "match_rules": "rule %{IPORHOST:client_ip} - %{USER:auth} \\[%{HTTPDATE:timestamp}\\] \"%{WORD:method} %{NOTSPACE:path} HTTP/%{NUMBER:http_version}\" %{INT:status} %{INT:bytes} \"%{DATA:referrer}\" \"%{DATA:user_agent}\" %{INT:request_count} \"%{DATA:router_name}\" \"%{DATA:service_url}\" %{INT:duration_ms}ms",
    "support_rules": ""
  }
}

# Target Fields Created:
# client_ip (string), auth (string), timestamp (string), method (string), path (string), http_version (string), status (integer), bytes (integer), referrer (string), user_agent (string), request_count (integer), router_name (string), service_url (string), duration_ms (integer)

OpenTelemetry Collector (transform processor)

regex_parser

# ==============================================================================
# OpenTelemetry Collector Configuration (otel-collector-config.yaml)
# Option 1: Filelog Receiver with regex_parser Operator
# ==============================================================================
receivers:
  filelog:
    include: [ /var/log/**/*.log ]
    start_at: beginning
    operators:
      - type: regex_parser
        id: logpipeline_regex_parser
        regex: '^(?<client_ip>(?:(?:(?:(?:(?:(?:[0-9A-Fa-f]{1,4}:){7}[0-9A-Fa-f]{1,4}|(?:[0-9A-Fa-f]{1,4}:){1,7}:|(?:[0-9A-Fa-f]{1,4}:){1,6}:[0-9A-Fa-f]{1,4}|(?:[0-9A-Fa-f]{1,4}:){1,5}(?::[0-9A-Fa-f]{1,4}){1,2}|(?:[0-9A-Fa-f]{1,4}:){1,4}(?::[0-9A-Fa-f]{1,4}){1,3}|(?:[0-9A-Fa-f]{1,4}:){1,3}(?::[0-9A-Fa-f]{1,4}){1,4}|(?:[0-9A-Fa-f]{1,4}:){1,2}(?::[0-9A-Fa-f]{1,4}){1,5}|[0-9A-Fa-f]{1,4}:(?:(?::[0-9A-Fa-f]{1,4}){1,6})|:(?:(?::[0-9A-Fa-f]{1,4}){1,7}|:)|fe80:(?::[0-9A-Fa-f]{0,4}){0,4}%[0-9a-zA-Z]+|::(?:ffff(?::0{1,4})?:)?(?:(?:25[0-5]|(?:2[0-4]|1?[0-9])?[0-9])\.){3}(?:25[0-5]|(?:2[0-4]|1?[0-9])?[0-9])|(?:[0-9A-Fa-f]{1,4}:){1,4}:(?:(?:25[0-5]|(?:2[0-4]|1?[0-9])?[0-9])\.){3}(?:25[0-5]|(?:2[0-4]|1?[0-9])?[0-9])))|(?:(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?))))|(?:\b(?:[0-9A-Za-z][0-9A-Za-z-]{0,62})(?:\.(?:[0-9A-Za-z][0-9A-Za-z-]{0,62}))*(?:\.?|\b)))) - (?<auth>(?:[a-zA-Z0-9._-]+)) \[(?<timestamp>(?:(?:(?:0[1-9])|(?:[12][0-9])|(?:3[01])|[1-9]))/(?:\b(?:Jan(?:uary)?|Feb(?:ruary)?|Mar(?:ch)?|Apr(?:il)?|May|Jun(?:e)?|Jul(?:y)?|Aug(?:ust)?|Sep(?:tember)?|Oct(?:ober)?|Nov(?:ember)?|Dec(?:ember)?)\b)/(?:\b[0-9]{4}\b):(?:(?:(?:(?:2[0123]|[01]?[0-9])):(?:(?:[0-5][0-9]))(?::(?:(?:(?:[0-5]?[0-9]|60)(?:[:.,][0-9]+)?))))) (?:(?:Z|[+-](?:(?:2[0123]|[01]?[0-9]))(?::?(?:(?:[0-5][0-9]))))))\] "(?<method>\b\w+\b) (?<path>\S+) HTTP/(?<http_version>(?:(?:(?:[+-]?(?:[0-9]+(?:\.[0-9]+)?|\.[0-9]+)))))" (?<status>(?:[+-]?(?:[0-9]+))) (?<bytes>(?:[+-]?(?:[0-9]+))) "(?<referrer>.*?)" "(?<user_agent>.*?)" (?<request_count>(?:[+-]?(?:[0-9]+))) "(?<router_name>.*?)" "(?<service_url>.*?)" (?<duration_ms>(?:[+-]?(?:[0-9]+)))ms$'
        timestamp:
          parse_from: attributes.timestamp
          layout: '%Y-%m-%dT%H:%M:%S%z'

# ==============================================================================
# Option 2: Transform Processor (OTel Transformation Language - OTTL)
# ==============================================================================
processors:
  transform:
    error_mode: ignore
    log_statements:
      - context: log
        statements:
          - merge_maps(attributes, extract_patterns(body, "^(?<client_ip>(?:(?:(?:(?:(?:(?:[0-9A-Fa-f]{1,4}:){7}[0-9A-Fa-f]{1,4}|(?:[0-9A-Fa-f]{1,4}:){1,7}:|(?:[0-9A-Fa-f]{1,4}:){1,6}:[0-9A-Fa-f]{1,4}|(?:[0-9A-Fa-f]{1,4}:){1,5}(?::[0-9A-Fa-f]{1,4}){1,2}|(?:[0-9A-Fa-f]{1,4}:){1,4}(?::[0-9A-Fa-f]{1,4}){1,3}|(?:[0-9A-Fa-f]{1,4}:){1,3}(?::[0-9A-Fa-f]{1,4}){1,4}|(?:[0-9A-Fa-f]{1,4}:){1,2}(?::[0-9A-Fa-f]{1,4}){1,5}|[0-9A-Fa-f]{1,4}:(?:(?::[0-9A-Fa-f]{1,4}){1,6})|:(?:(?::[0-9A-Fa-f]{1,4}){1,7}|:)|fe80:(?::[0-9A-Fa-f]{0,4}){0,4}%[0-9a-zA-Z]+|::(?:ffff(?::0{1,4})?:)?(?:(?:25[0-5]|(?:2[0-4]|1?[0-9])?[0-9])\\.){3}(?:25[0-5]|(?:2[0-4]|1?[0-9])?[0-9])|(?:[0-9A-Fa-f]{1,4}:){1,4}:(?:(?:25[0-5]|(?:2[0-4]|1?[0-9])?[0-9])\\.){3}(?:25[0-5]|(?:2[0-4]|1?[0-9])?[0-9])))|(?:(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?))))|(?:\\b(?:[0-9A-Za-z][0-9A-Za-z-]{0,62})(?:\\.(?:[0-9A-Za-z][0-9A-Za-z-]{0,62}))*(?:\\.?|\\b)))) - (?<auth>(?:[a-zA-Z0-9._-]+)) \\[(?<timestamp>(?:(?:(?:0[1-9])|(?:[12][0-9])|(?:3[01])|[1-9]))/(?:\\b(?:Jan(?:uary)?|Feb(?:ruary)?|Mar(?:ch)?|Apr(?:il)?|May|Jun(?:e)?|Jul(?:y)?|Aug(?:ust)?|Sep(?:tember)?|Oct(?:ober)?|Nov(?:ember)?|Dec(?:ember)?)\\b)/(?:\\b[0-9]{4}\\b):(?:(?:(?:(?:2[0123]|[01]?[0-9])):(?:(?:[0-5][0-9]))(?::(?:(?:(?:[0-5]?[0-9]|60)(?:[:.,][0-9]+)?))))) (?:(?:Z|[+-](?:(?:2[0123]|[01]?[0-9]))(?::?(?:(?:[0-5][0-9]))))))\\] \"(?<method>\\b\\w+\\b) (?<path>\\S+) HTTP/(?<http_version>(?:(?:(?:[+-]?(?:[0-9]+(?:\\.[0-9]+)?|\\.[0-9]+)))))\" (?<status>(?:[+-]?(?:[0-9]+))) (?<bytes>(?:[+-]?(?:[0-9]+))) \"(?<referrer>.*?)\" \"(?<user_agent>.*?)\" (?<request_count>(?:[+-]?(?:[0-9]+))) \"(?<router_name>.*?)\" \"(?<service_url>.*?)\" (?<duration_ms>(?:[+-]?(?:[0-9]+)))ms$"), "insert")

service:
  pipelines:
    logs:
      receivers: [filelog]
      processors: [transform]
      exporters: [otlp]

Logstash Filter Configuration

filter.grok

# ==============================================================================
# Logstash Pipeline Configuration (/etc/logstash/conf.d/logpipeline.conf)
# ==============================================================================
filter {
  grok {
    match => { "message" => "%{IPORHOST:client_ip} - %{USER:auth} \[%{HTTPDATE:timestamp}\] \"%{WORD:method} %{NOTSPACE:path} HTTP/%{NUMBER:http_version}\" %{INT:status:integer} %{INT:bytes:integer} \"%{DATA:referrer}\" \"%{DATA:user_agent}\" %{INT:request_count:integer} \"%{DATA:router_name}\" \"%{DATA:service_url}\" %{INT:duration_ms:integer}ms" }
    tag_on_failure => [ "_grokparsefailure" ]
  }

  date {
    match => [ "timestamp", "ISO8601", "dd/MMM/yyyy:HH:mm:ss Z" ]
    target => "@timestamp"
    remove_field => [ "timestamp" ]
  }
}