Manage Systemd Services with Systemctl on Ubuntu
Systemd is primarily an init system for Linux operating systems. It’s main task is to initialize the components that must…
Cloud Computing – Hyperscaler
What is a Hyperscaler? In short –> Scalable cloud computing systems in a data center like Amazon (AWS), Microsoft (Azure),…
Windows Local Administrators Group Membership on Azure AD joined Devices
What actually happens to the local administrators group membership when you join a windows device to Azure AD? Below to…
Convert pfSense into a Routing Only Platform
If you want to use pfSense just as a router to connect for example two different internal subnets, you need…
Secure WordPress with fail2ban
In a previously post I showed how to set up fail2ban on Ubuntu to prevent several services from brute-force attacks….
Email Authentication by using DMARC, DKIM and SPF
In this post I want to show how you can prevent that your email domain is abused for email spoofing…
Set up DMARC (verification) for Postfix on Ubuntu
Last week I wrote a post about how to set up SPF and DKIM for Postfix on Ubuntu, today I…
Set up DomainKeys Identified Mail (DKIM) for Exchange Online
Either you can set up DKIM by using the Microsoft 365 Defender portal or manually by using PowerShell. First I…
Configure Postfix to block and reject Unsolicited Messages or Spam
Below I want to show how to configure the built-in options for Postfix to prevent unsolicited commercial emails (UCE) or…
Set up Ubuntu’s Built-In Firewall
Ubuntu’s built-in firewall is named ufw (uncomplicated firewall). Actually Ufw is just an utility which makes it easier to configure…
