Configuring Mastodon Prometheus Metrics

With release 4.4.0 Mastodon introduced a Prometheus exporter. In this post, I will configure it and show the data it provides. With the new release, Mastodon provides metrics from Ruby and Sidekiq. I’ve attached examples for both to this post, see here for Ruby and here for Sidekiq. The information is not actually that interesting, it’s just generic process data. But I did find at least the Sidekiq data worth gathering. It will provide an interesting future look into my usage of Mastodon and perhaps even the activity in the Fediverse (or at least the part I’m connected to) overall. ...

July 12, 2025 · 3 min · Michael
The HashiCorp Nomad and Kubernetes logos, connected with an arrow pointing from Nomad to Kubernetes

Nomad to k8s, Part 20: Migrating Mastodon

Wherein I migrate my Mastodon instance to the k8s cluster. This is part 21 of my k8s migration series. Mastodon is currently serving as my presence in the Fediverse. You can find me here, although I’m pretty sure that most of my readers are coming from there already. 😄 If you’re at all interested in joining a genuine community around Homelabbing, I can only recommend to join the fun by following the HomeLab or SelfHosted hashtags and wildly following everyone appearing on there. It’s a great community of rather friendly people enjoying everything from a lonely Pi to several 42U 19" racks full of equipment. If you’re interested in learning more about my own experience with the Fediverse and hosting my own single-user instance, have a look at these older posts. ...

March 6, 2025 · 8 min · Michael
A screenshot of a Grafana visualization titled 'Objects in cluster'. It shows a pretty consistent growth until about October 10th, where the first drop of about 150k objects occurs. Then a far steeper drop follows on October 19th to 21st, straight down from 1.9 million to 1 million. Afterwards, there is regular growth again, but now interspersed with similarly regular drops in the object counts.

Cleaning up my Mastodon Media Cache

I recently randomly wandered onto the Mastodon admin page. What I saw there will shock you. (I’m so sorry about that introduction) That’s perhaps a bit much in the Media storage area for a single user instance. I was pretty sure that I had previously configured Mastodon’s media cache retention to 7 days. Checking up on that, I found that I had remembered correctly. ...

November 27, 2024 · 14 min · Michael

How to configure Mastodon link verification

To distract myself from the fact that the last commit in the repo for my k8s Backup Operator was about one month ago, I decided to tackle a random assortment of tasks. One of them was to finally set up link verification for my Blog on Mastodon. It looks like this when it’s working: My Mastodon profile with the link to this blog properly verified, as indicated by the green check mark. ...

November 14, 2024 · 3 min · Michael

Reflecting on 1 year in the Fediverse

I started my Fediverse journey a little over a year ago, with my account creation date being August 3rd, 2022. I was initially drawn to the Fediverse due to the simple fact that this was social media I could host myself. Neat, right? And I want to reflect a little bit on how it’s going. So let’s start with my social media usage in the past, so you can properly classify where the following comments are coming from. ...

August 6, 2023 · 15 min · Michael