Posts

Overview In the previous post, I talked about Network IP Fragmentation, what it is and why it’s needed (You are advised to read it before continuing). I also covered the so called PMTUD Black hole effect. Fixing a PMTUD Black hole is a multistep process, and it starts with finding the correct MTU/MRU of your link. Now as I’ve discussed, every path can have its own unique MTU/MRU value, but we are usually interested in the max value that is dictated by your ISP.

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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.

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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…

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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.

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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…

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

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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…

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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.

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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.

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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.

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