This guide will show you how to harden your Debian Buster server by setting up UFW (Uncomplicated Firewall), Fail2Ban and modifying SSH configuration.

Currently there isn’t an official GitLab Runner Executor for Podman. Due to RedHat Enterprise Linux 8 replacing Docker with Podman I had to find a simple solution for getting my Runners with Docker Executors running on RHEL8 without installing Docker natively or having to write a custom executor from scratch. The trick is to run a Podman Container running Docker inside and sharing it’s Docker Socket as a volume between containers!

Keycloak is a great Identity and Access Managment (IAM) solution but lacks currently the ability of sending notification emails to the administrator. As an admin it is crucial beeing notified when a new user registers to take further actions like granting a user specific roles and permissions. Thankfully Keycloak offers an extensive Rest API that we can use to fetch and further process user events. In this guide we will write a Python script using the Python Keycloak library. The script will run regulary as a cronjob and send emails on registration events.