Linux

The worlds best (and most complicated) OS

Improve your storage I/O performance today

~ Jannik Smidt

an article by Lucas Crämer and Jannik Smidt

DISCLAIMER

This post tries to keep the complexity manageable while making a point clear. We are not systems engineers/kernel developers, so feel free to point out any mistakes/misunderstandings. This post probably does not present anything new for people who are working in systems engineering and/or kernel development.

Why is that of any interest to an application developer?

Storage is getting faster and faster, while the performance of single CPU cores does not increase to the same degree. Blazingly fast NVMe Storage Devices have reached PCs, Smartphones, Gaming Consoles, and Server Systems in the Cloud. The importance of fast and low latency storage in the cloud can not be understated. AWS recently even went that far to develop and release their own SSDs (AWS Nitro SSD) based on the AWS Nitro System for specific EC2 instance types [1]. 

Many application developers are not particularly educated about storage hardware, kernels, and file system APIs. This post is basically what application programmers should know when programming with modern storage devices in mind.

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KISS, DRY ‘n SOLID — Yet another Kubernetes System built with Ansible and observed with Metrics Server on arm64

~ Artur Bergen

This blog post shows how a plain Kubernetes cluster is automatically created and configured on three arm64 devices using an orchestration tool called Ansible. The main focus relies on Ansible; other components that set up and configure the cluster are Docker, Kubernetes, Helm, NGINX, Metrics Server and Kubernetes Dashboard. Individual steps are covered more or less; the whole procedure follows three principles:

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Behind the scenes of modern operating systems — Security through isolation (Part 1)

~ Leon Klingele

In recent years, since the Internet has become available to almost anyone, application and runtime security is important more than ever. Be it an (unknown) application you download and run from the Internet or some server application you expose to the Internet, it’s almost certainly a bad idea to run apps without any security restrictions applied:
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Livestreaming with libav* – Tutorial (Part 1)

~ Benjamin Binder

Green screen live streaming production at Mediehuset København. Author: Rehak

Lifestreaming is the real deal of video today, however there aren’t that many content creation tools to choose from. YouTube, Facebook and Twitter are pushing hard to enable their users to stream vlogging-style content live from their phones with proprietary Apps, and OBS is used for Let’s Plays and Twitch streams. But when you want to stream events or lectures you are pretty much on your own.

In this series of posts I want to share the experiences I gained over the past couple of weeks while writing an application that captures video and audio and creates a simple livestream. This application is designed to be the basis of a simple streaming desktop application.  Continue reading →

Exploring Docker Security – Part 2: Container flaws

~ Patrick Kleindienst

http://i.dailymail.co.uk/i/pix/2010/08/10/article-1301858-0ABD7881000005DC-365_964x543.jpg

Now that we’ve understood the basics, this second part will cover the most relevant container threats, their possible impact as well as existent countermeasures. Beyond that, a short overview of the most important sources for container threats will be provided. I’m pretty sure you’re not counting on most of them. Want to know more?

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Exploring Docker Security – Part 1: The whale’s anatomy

~ Patrick Kleindienst

http://imagenes.4ever.eu/data/download/animales/la-vida-acuatica/ballena-de-alas-largas-240873.jpg

When it comes to Docker, most of us immediately start thinking of current trends like Microservices, DevOps, fast deployment, or scalability. Without a doubt, Docker seems to hit the road towards establishing itself as the de-facto standard for lightweight application containers, shipping not only with lots of features and tools, but also great usability. However, another important topic is neglected very often: Security. Considering the rapid growth of potential threats for IT systems, security belongs to the crucial aspects that might decide about Docker (and generally containers) being widely and long-term adopted by software industry.
Therefore, this series of blog posts is about giving you an overview of the state of the art as far as container security (especially Docker) is concerned. But talking about that does not make so much sense without having a basic understanding of container technology in general. This is what I want to cover in this first part.
You may guessed right: Altogether, this will be some kind of longer read. So grab a coffee, sit down and let me take you on a whale ride through the universe of (Docker) containers.

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More docker = more power? – Part 2: Setting up Nginx and Docker

~ Moritz Lottermann

This is Part 2 of a series of posts. You can find Part 1 here: https://blog.mi.hdm-stuttgart.de/index.php/2016/01/03/more-docker-more-power-part-1-setting-up-virtualbox/

In the first part of this series we have set up two VirtualBox machines. One functions as the load balancer and the other will house our services. As the next step we want to install docker on the service VM. To do that enter the following commands in the bash:

$ wget -qO- https://get.docker.com/ | sh
$ sudo gpasswd -a <username> docker
$ newgrp docker

This downloads and installs Docker, adds your user to the docker user group and logs you into this new group to allow you to create and run containers.

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