Author Archives: Matthias

Testing Alertmanager

Posted on September 13, 2020 by Matthias

When a Prometheus alerting rule fires, the Prometheus server sends a notification to the Alertmanager, which is then responsible for processing that alert further, i.e. by routing it to an appropriate alerting channel (e-mail, Slack, …). In order to test … Continue reading →

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Playing with WebAuthn

Posted on September 8, 2019 by Matthias

On the internet today, our online accounts are exposed to a lot of risks. Leaked passwords from break-ins at major Internet properties or phishing attacks have lead to many account breaches. In order to protect my high-value accounts, I have … Continue reading →

Posted in best practices | Tagged , | 2 Comments

Using Kubectl Printers and Plugins

Posted on April 22, 2019 by Matthias

Even though we have plenty of metrics and dashboards at work, I use the kubectl command line tool a lot for looking at resources and for troubleshooting. Because the defaults don’t always display the information that I need, I often … Continue reading →

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Monitoring Log Statements in Go

Posted on March 3, 2019 by Matthias

Good monitoring and alerting are essential for running services in production. As a Java developer, I’m a bit spoiled by my platform of choice, Spring Boot 2. Thanks to Micrometer it provides out of the box instrumentation for HTTP requests, … Continue reading →

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Additional Workspaces in Gnome

Posted on February 24, 2019 by Matthias

I use Gnome on Ubuntu 18.04 with static workspaces and switch between them using keyboard shortcuts – for example, ALT+1 takes me to workspace one. Unfortunately, using the graphical settings editor, I was only able to assign keyboard shortcuts to … Continue reading →

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Retries Can Kill You

Posted on July 30, 2018 by Matthias

In a large-scale distributed system, it’s inevitable that some requests will fail. Even if your collaborating systems work perfectly, sooner or later you will experience temporary network issues and other intermittent errors. That’s why a lot of people try to … Continue reading →

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Prometheus and Spring Boot Health Checks

Posted on June 24, 2018 by Matthias

When trying to set up alerting for Spring Boot services with Prometheus, I discovered the synthetic “up” time series which is great for checking whether the monitoring system can reach my service instances. While this is a great thing, I also … Continue reading →

Posted in java | Tagged | 5 Comments

DNS Over HTTPS

Posted on April 8, 2018 by Matthias

With much of the web switching to HTTPS and at least some people becoming more concerned about privacy, DNS has recently come into the spotlight because it provides an ISP with the ability to monitor which websites a user visits. … Continue reading →

Posted in misc | Tagged , , | 2 Comments