docs: storage: dead-letter-queue: document new config parameter

[eschabell]

docs: storage: config: yaml: service-section:

  - add storage.rejected.limit row to storage parameters table

docs: storage: dead-letter-queue:

  - added storage.rejected.limit and "Limit DLQ size" section with YAML example

Note, for code change with no matching docs PR.

Summary by CodeRabbit

• Documentation
  • Added documentation for configuring dead letter queue size limits, explaining how to set a maximum size for rejected chunks and the system behavior when the limit is reached, along with practical configuration examples.

[coderabbitai]

📝 Walkthrough

Walkthrough

This pull request extends Fluent Bit documentation to cover a new DLQ size limit feature. The storage.rejected.limit configuration option is added to the service section reference table and documented in detail within the dead-letter-queue guide, including behavior and example configuration.

Changes

DLQ Size Limit Configuration Documentation

Layer / File(s)	Summary
DLQ size limit configuration reference and guide administration/configuring-fluent-bit/yaml/service-section.md, administration/dead-letter-queue.md	Adds storage.rejected.limit key to the service configuration table and introduces a "Limit DLQ size" section in the DLQ documentation, explaining that this setting caps the total rejected chunk size, causes new chunks to be skipped with a warning once the limit is reached, and defaults to unlimited when unset. Includes an example service configuration with storage.rejected.limit: 500M.

Estimated code review effort

🎯 1 (Trivial) | ⏱️ ~3 minutes

Possibly related PRs

• fluent/fluent-bit-docs#2208: Updates the DLQ-related documentation in service section and DLQ pages by extending Fluent Bit's service.storage.rejected.* configuration.
• fluent/fluent-bit-docs#2166: Adds documentation for other DLQ-related service.storage.rejected.* parameters (storage.keep.rejected, storage.rejected.path) under the same storage/DLQ configuration area.
• fluent/fluent-bit-docs#2324: Extracts and rewires the DLQ documentation that this PR extends with the new service.storage.rejected.limit behavior.

Suggested labels

5.0.5

Suggested reviewers

• cosmo0920
• esmerel

Poem

🐰 A queue grows deep, but now has bounds,
With rejected.limit's gentle sound,
Chunks skip past when size is reached,
While warnings log and docs are preached,
The DLQ finds its rightful place!

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title directly and specifically describes the main change: documenting a new storage configuration parameter for the dead-letter-queue feature.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

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[coderabbitai]

🧹 Nitpick comments (1)

administration/dead-letter-queue.md (1)

69-80: 💤 Low value

Consider adding the new parameter to this example.

The general DLQ example could optionally include storage.rejected.limit to demonstrate best practices for preventing unbounded growth. However, since the parameter is optional and already documented with a complete example in the "Limit DLQ size" section above, the current approach is acceptable.

🤖 Prompt for AI Agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In `@administration/dead-letter-queue.md` around lines 69 - 80, Add the optional
storage.rejected.limit parameter to the DLQ example so readers see a
best-practice for bounding DLQ size; update the YAML block that defines service
and storage keys (e.g., storage.rejected.path, storage.keep.rejected) to include
storage.rejected.limit with an example value (such as "100M" or a small integer)
and a brief inline comment if desired to indicate it prevents unbounded growth.

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Nitpick comments:
In `@administration/dead-letter-queue.md`:
- Around line 69-80: Add the optional storage.rejected.limit parameter to the
DLQ example so readers see a best-practice for bounding DLQ size; update the
YAML block that defines service and storage keys (e.g., storage.rejected.path,
storage.keep.rejected) to include storage.rejected.limit with an example value
(such as "100M" or a small integer) and a brief inline comment if desired to
indicate it prevents unbounded growth.

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro

Run ID: 006a695c-6603-40a2-b56e-be1584c7e477

📥 Commits

Reviewing files that changed from the base of the PR and between d3d0a7a and 9b44903.

📒 Files selected for processing (2)

• administration/configuring-fluent-bit/yaml/service-section.md
• administration/dead-letter-queue.md

[eschabell]

@cosmo0920 can you review this?