Welcome to Larvitz Blog! I’m Christian, a Cloud Consultant by day and FreeBSD enthusiast by night, with over 20 years in enterprise IT. Here I write about FreeBSD jails, PF firewalling, self-hosting, Linux system administration, and anything that’s cleanly engineered. Most articles are hands-on guides born from running my own infrastructure, from dual-stack networking and Ansible automation to hosting a Mastodon instance on FreeBSD.

Have a question or want to discuss something? Find me on the Fediverse at @Larvitz@burningboard.net. I’m always happy to chat!

#summer Articles

Sun 07 June 2026
DIY

A Monoblock AC Is Only as Good as Its Window Seal

I moved into a top-floor 1970s apartment in one of the warmest corners of Germany, work from home, and needed the office to stay below “thinking is hard now”. A single-hose portable AC is a thermodynamically compromised machine, but most of what makes it bad happens at the window. Here is the personal story, a short detour into why these units leak, and the cheap XPS panel I cut to fix the part that actually matters.