Posts

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.
Dec 11, 2018 8 min read Tutorial
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.
Oct 9, 2018 11 min read Tutorial
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…
Sep 19, 2018 3 min read Blog
How to install LUKS encrypted Ubuntu 18.04.x Server and enable remote unlocking
Much has been changed since my last post about LUKS remote unlock workaround. This is the updated version on how to set things up properly.
Last updated on Sep 24, 2019 9 min read Tutorial
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…
May 31, 2018 5 min read Blog
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…
May 6, 2018 4 min read Blog
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…
Sep 9, 2017 6 min read Blog
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.
Last updated on Sep 17, 2018 6 min read Blog
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.

Last updated on May 31, 2018 4 min read Blog
Optimizing OpenVPN Throughput

In the previous post, I talked about OpenVPN TCP and UDP tunnels and why you should not be using TCP. In this post, I’m going to talk about optimizing the said tunnels to get the most out of them.

Last updated on Jan 18, 2019 9 min read Blog