MySQL server logs with OpenTelemetry

Collect logs from a self-hosted MySQL server — the error log and the slow query log — with the OpenTelemetry Collector. The same Collector can also forward traces and metrics from your apps — see Connect OpenTelemetry Collector to Bronto.

Prerequisites

A Bronto account and API key (how to create one)
MySQL writing logs to disk. The default error log on Debian/Ubuntu is /var/log/mysql/error.log
An OpenTelemetry Collector (recommended) or Fluent Bit installed on the same host

Enable the slow query log in my.cnf to capture queries worth investigating:

my.cnf

[mysqld]
slow_query_log      = 1
slow_query_log_file = /var/log/mysql/mysql-slow.log
long_query_time     = 1

Configure the Collector

Error and slow-query entries can span multiple lines. Use multiline keyed on the leading timestamp or the slow-log # Time: header:

/etc/otel/config.yaml

receivers:
  filelog/mysql:
    include:
      - /var/log/mysql/error.log
      - /var/log/mysql/mysql-slow.log
    multiline:
      line_start_pattern: '^(\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}|# Time:)'
    resource:
      service.name: mysql
      service.namespace: <YOUR_COLLECTION_NAME>

processors:
  batch:

exporters:
  otlphttp/brontologs:
    logs_endpoint: "https://ingestion.<REGION>.bronto.io/v1/logs"
    compression: gzip
    headers:
      x-bronto-api-key: <YOUR_API_KEY>

service:
  pipelines:
    logs:
      receivers: [filelog/mysql]
      processors: [batch]
      exporters: [otlphttp/brontologs]

Set <REGION> to eu or us.

What you will see in Bronto

Open Search and filter by service.name = mysql. The error log carries startup/shutdown, errors, and warnings (timestamp, thread ID, severity, subsystem); the slow query log carries each slow statement with Query_time, Lock_time, Rows_examined, and the SQL text. Bronto’s Custom Parser extracts these fields server-side.

Troubleshooting

Where are the logs? Run SHOW VARIABLES LIKE 'log_error'; and SHOW VARIABLES LIKE 'slow_query_log_file';. Adjust the include paths to match.
General query log: disabled by default and very verbose — enable (general_log = 1) only for short debugging sessions.
For general issues, see OTel Collector troubleshooting.

Alternative: Fluent Bit

If you already run Fluent Bit, tail the MySQL log files and forward them over HTTP:

fluent-bit.conf

[INPUT]
    name  tail
    path  /var/log/mysql/error.log,/var/log/mysql/mysql-slow.log
    tag   mysql

[OUTPUT]
    name        http
    match       mysql
    host        ingestion.<REGION>.bronto.io
    port        443
    tls         on
    format      json_lines
    compress    gzip
    header      x-bronto-api-key    <YOUR_API_KEY>
    header      x-bronto-dataset    mysql
    header      x-bronto-collection <YOUR_COLLECTION_NAME>

Set Format to json_lines, not json. For slow-query entries that span lines, add a multiline.parser keyed on the # Time: header. See Connect Fluent Bit to Bronto.

Overview

Ingest with agents

Ingest from AWS

Ingest from Azure

Ingest from CDN and edge

Ingest from apps and platforms

Ingest from infrastructure and databases

Ingest OpenTelemetry data

MySQL server logs with OpenTelemetry

Prerequisites

Configure the Collector

What you will see in Bronto

Troubleshooting

Alternative: Fluent Bit

​Prerequisites

​Configure the Collector

​What you will see in Bronto

​Troubleshooting

​Alternative: Fluent Bit

Prerequisites

Configure the Collector

What you will see in Bronto

Troubleshooting

Alternative: Fluent Bit