Systemd

Introduction to systemd-resolved

I’ve spent years working with Linux, and one component that’s given me trouble is systemd-resolved, the DNS resolver service that comes bundled with systemd. Recently, I noticed my DNS queries were leaking, and I was getting annoying resolver errors on my Linux desktop. This prompted me to dive deeper into systemd-resolved and figure out how to tame it. I’ve seen this go wrong when people don’t take the time to understand how it works, so let’s start with the basics.

Introduction to journalctl Filtering

I’ve been using journalctl for years, and I’ve learned that it can be overwhelming if you don’t know how to filter the noise. By default, journalctl displays a vast amount of information that may not be relevant to your current needs. In this article, I’ll share how I tame the noise in journalctl using custom filters and priorities.

Understanding journalctl Basics

Before we dive into filtering, let’s cover some journalctl basics. The command journalctl is used to query the systemd journal, which stores log messages from various system components, including systemd services, kernel messages, and other system logs. I usually start with a simple command to view the most recent journal logs:

Introduction to Slow Boot Times

I’ve had my fair share of slow boot times on Linux. When I upgraded my desktop to the latest version of my distribution in 2025, I noticed some new systemd services that were slowing down my boot process. The real trick is identifying which services are causing the issue. After digging around, I found that some of these services weren’t essential for my daily usage, and disabling them made a significant difference.

Introduction to Container Logs

I’ve been running a homelab with various self-hosted services for a while now, and managing container logs has been a challenge. With containerization making it easy to spin up multiple containers, keeping track of their logs can be overwhelming. In my experience, using Podman and systemd-journald has been a game-changer for taming container logs.

What are Container Logs?

Container logs are essentially the output of a container’s stdout and stderr streams. They contain valuable information about the container’s execution, such as errors, warnings, and debug messages. By default, container logs are stored in the container’s filesystem, which can lead to log rotation issues and make it difficult to manage logs across multiple containers. I’ve seen this go wrong when logs start filling up the container’s disk space, causing all sorts of issues.

Introduction to DNS Troubles

I’ve been running my homelab for years, and one thing that still gets me is DNS troubles. Last year, I decided to set up systemd-resolved and dnsmasq to manage my home network’s DNS. The idea was to use systemd-resolved as the primary resolver and dnsmasq as a caching layer to improve performance. Sounds simple, but it didn’t quite work out that way.

Setting Up systemd-resolved

To start, I enabled systemd-resolved on my Ubuntu-based server. This involved editing the /etc/systemd/resolved.conf file to set the DNS servers and domains. I opted for Cloudflare’s DNS servers - they’re known for being fast and secure.

Introduction to Slow System Boot Times

I’ve seen this go wrong when a slow system boot time brings your entire workflow to a crawl. Whether you’re running a homelab server or a desktop Linux installation, a slow boot can be frustrating. In this article, we’ll explore how to troubleshoot slow system boot times using systemd-analyze and other practical tools.

Understanding systemd-analyze

The real trick is to use systemd-analyze to get a detailed breakdown of the boot process. This powerful tool provides insights into the time spent on each service and the overall boot time. To use systemd-analyze, simply run:

Introduction to Systemd Boot Times

I’ve seen my fair share of slow-booting Linux systems over the years, and it’s frustrating when you’re waiting for your system to start up. With modern hardware and Linux distributions, boot times should be relatively fast, but misconfigured services, unnecessary dependencies, and inefficient system initialization can still cause issues. That’s where systemd-analyze comes in - it’s an invaluable tool for identifying bottlenecks and optimizing your system’s performance.

Introduction to Disk Full Alerts

I’ve lost count of how many times I’ve received disk full alerts on my home server. It’s frustrating, especially when it happens at the worst possible moment. Last year, I had a particularly annoying issue that prompted me to take a closer look at my disk usage. I realized I needed to make some changes to prevent these issues in the future. In this article, I’ll walk you through the steps I took to resolve disk full alerts on my server by implementing quotas and cleaning up systemd journal logs.

Introduction to journalctl

I’ve been using Linux for years, and journalctl has become an essential tool in my daily workflow. If you’re like me, you’re probably familiar with the journalctl command, which is used to query and display logs from systemd’s journal. However, with the vast amount of data that’s logged, it can be overwhelming to sift through and find the information you need. In this article, I’ll share some practical tips and tricks for filtering out noise and finding useful error messages in your system logs using journalctl.

Introduction to Log Rotation

I’ve seen log rotation become a major issue on small servers with high IO workloads - it’s a problem that can sneak up on you quickly. Logs can grow at an alarming rate, and if you don’t manage them properly, they can fill up your disk space in no time. The real trick is to stay on top of log rotation, and that’s where tools like logrotate come in.