# Logging Style Guide

> [crefft](/index.md) > [Infrastructure](/guides/infrastructure.md) > Logging

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC 2119](https://datatracker.ietf.org/doc/html/rfc2119).

## Quick Reference

| Task           | Tool       | Command                    |
| -------------- | ---------- | -------------------------- |
| View logs      | journalctl | `journalctl -f`            |
| Filter by unit | journalctl | `journalctl -u nginx`      |
| Export logs    | journalctl | `journalctl --output=json` |

## Overview

TODO: Centralized logging architecture for infrastructure.

## journald Configuration

TODO: `/etc/systemd/journald.conf`, storage, retention.

## Structured Logging

TODO: JSON logging, log levels, correlation IDs.

## Log Aggregation

TODO: Loki, Vector, or rsyslog forwarding.

## Log Retention

TODO: Rotation policies, compliance requirements.

## Security

TODO: Log integrity, tamper detection, access control.

## See Also

* [Linux Guide](/guides/infrastructure/os/linux.md) — Base OS configuration
* [Monitoring Guide](/guides/process.md) — Metrics and alerting

---

Source version: 2026.10.4. [Source file](https://github.com/agh/crefft/blob/703c8156f7604b464921c851535242202541cfb3/guides/infrastructure/services/logging.md).