Troubleshooting

How to compile OpenWrt and still use the official repository

In this post, I discuss why you would want to build OpenWrt yourself, and how to do so in a way that you still would be able to use the official repositories.

How I lost my data trying to back it up

This is a story about how I lost my data when trying to prevent it by backing it up.

How to find the correct MTU and MRU of your link

Fixing a PMTUD Black hole is a multistep process, and it starts with finding the correct MTU/MRU of your link. In this post, I will explain how to do just that.

Understanding Network IP Fragmentation

In this post, I'm going to talk about what IP fragmentation is, how it works and why it's needed. And while learning that, we're going to touch on subjects like OSI Layers / PDU / MTU / MRU and PMTUD.

Windows XP OpenVPN TAP installation, "devcon.exe failed"

Recently I had to install OpenVPN on a system running Windows XP (Don't ask). The installation went smoothly up until TAP driver installation and then suddenly things went haywire...

How to Fully Uninstall Kaspersky's NDIS Filter

I like Kaspersky anti-virus, and I use it regularly… (Not on my own PC mind you, but on the clients) While I do believe they provide the best anti-virus in the market, I am not a fan of most of their other products. That goes for the Firewall, Safe Browsing, SSL Hijacking, and of course their newest addition, Secure Connection…

OpenDKIM-OpenDMARC and a Chrooted Postfix Instance

Compatibility issues arises when using OpenDKIM/OpenDMARC Unix sockets with chrooted Postfix installation. In this post you will learn to resolve this...

The Tale of Windows UAC and Incompetent Programmers

In this post i will give you a brief history of UAC, an overall overview, and how programmers abuse the system. I also talk about different ways to manipulate an applications manifest to turn on UAC virtualization, and much more...

Remote unlocking of LUKS-encrypted root in Ubuntu/Debian

Not so long ago, remote unlocking of a LUKS-encrypted root partition was difficult to setup. While essential for headless servers, all required steps needed to be done manually and compatibility was a concern. Luckily, it is much simpler to do so in recent versions of Ubuntu/Debian. Unlocking an encrypted root remotely *should* be as simple as installing a single package... We'll see about that in a moment.

OpenVPN TAP adapter MTU in Windows

Recently I was in need of setting up some windows clients to connect to my OpenVPN server. This server running on Linux, uses a specific MTU value (let’s say 1400) to ensure maximum compatibility with different clients over different links.