[Nginx]: Add configuration examples for Nginx logs compatible with the integration in the documentation

[RockD]

Integration Name

Nginx [packages/nginx]

Dataset Name

nginx.access (and nginx.error)

Integration Version

3.2.2

Agent Version

9.4.4

OS Version and Architecture

RHEL 9 x86_64

User Goal

We are using the Nginx integration with Elastic Agent to collect and parse access and error logs. However, the current documentation lacks clear, practical examples of Nginx log_format configurations that are fully compatible with the integration's default parsing pipeline.

We would like to see official configuration examples added to the documentation or integration overview page that show:

• The recommended Nginx log_format directive to use with the integration.
• Examples for both access logs and error logs.

Example of a custom log format that users might try:

log_format custom '$remote_addr - $remote_user [$time_local] "$request" $status $body_bytes_sent "$http_referer" "$http_user_agent" $request_time $upstream_response_time';

Adding these examples would significantly improve the user experience and reduce prep time.

Existing Features

The current documentation describes how to enable the integration and configure basic paths for log files, but it does not provide concrete log_format examples. Users are left to guess which fields are expected by the integration's ingest pipeline. It would be useful to have in hand a direct example.

What did you see?

Currently, when users configure a custom log_format in Nginx that deviates from the default combined format, the integration may fail to parse logs correctly, resulting in:

• Missing or incorrectly mapped fields in Elasticsearch.
• Users having to reverse-engineer the integration's pipeline to understand the expected format.

Anything else?

It would be very helpful if the documentation included:

1. The default log format that the integration expects (if any).
2. A recommended log_format that works out of the box with the integration with all features.
3. Examples of common customizations (e.g., adding response time, upstream status, etc.) and how to adjust the integration's processor configuration to handle them.