Send logs from JournalD to NATS

A simple guide to send logs from JournalD to NATS in just a few minutes.
type: tutorialdomain: sourcesdomain: sinkssource: journaldsink: nats

Logs are an essential part of observing any service; without them you'll have significant blind spots. But collecting and analyzing them can be a real challenge -- especially at scale. Not only do you need to solve the basic task of collecting your logs, but you must do it in a reliable, performant, and robust manner. Nothing is more frustrating than having your logs pipeline fall on it's face during an outage, or even worse, cause the outage!

Fear not! In this guide we'll build an observability pipeline that will send logs from JournalD to NATS.

Background

What is JournalD?

Journald is a utility for accessing log data across a variety of system services. It was introduced with Systemd to help system administrators collect, access, and route log data.

What is NATS?

NATS.io is a simple, secure and high performance open source messaging system for cloud native applications, IoT messaging, and microservices architectures. NATS.io is a Cloud Native Computing Foundation project.

Strategy

How This Guide Works

We'll be using [Vector][urls.vector_website] to accomplish this task. Vector is a popular open-source observability data pipeline. It's written in Rust, making it lightweight, ultra-fast and highly reliable. And we'll be deploying Vector as a agent.

Vector daemon deployment strategyVector daemon deployment strategy
1. Your service logs to STDOUT
STDOUT follows the 12 factor principles.
2. STDOUT is captured
STDOUT is captured and sent to JournalD.
3. Vector collects & fans-out data
Vector will sends logs to [NATS](https://nats.io/).

What We'll Accomplish

We'll build an observability data pipeline that:

  • Collects logs from JournalD.
    • Enriches data with useful JournalD context.
    • Efficiently collects data and checkpoints read positions to ensure data is not lost between restarts.
  • Sends logs to NATS.
    • Compresses data to optimize bandwidth.
    • Automatically retries failed requests, with backoff.
    • Securely transmits data via Transport Layer Security (TLS).

All in just a few minutes!

Tutorial

  1. Install Vector

    curl --proto '=https' --tlsv1.2 -sSf https://sh.vector.dev | sh
  2. Configure Vector

    cat <<-'VECTORCFG' > ./vector.toml
    [sources.journald]
    type = "journald"
    [sinks.out]
    type = "nats"
    inputs = [ "journald" ]
    subject = "{{ host }}"
    url = "nats://demo.nats.io"
    encoding.codec = "json"
    VECTORCFG
  3. Start Vector

    vector --config ./vector.toml
  4. Observe Vector

    vector top
    explain this command

Next Steps

Vector is powerful tool and we're just scratching the surface in this guide. Here are a few pages we recommend that demonstrate the power and flexibility of Vector:

Vector Github repo 4k
Vector is free and open-source!
Vector quickstart
Get setup in just a few minutes
Vector documentation
Everything you need to know about Vector

[urls.vector_website]: