Blog

All Blog Posts for Vagrant


  • Icinga2 Fine-Tuning

    Icinga2 Fine-Tuning

               Icinga2 is a great tool built upon the foundation of the well known Nagios monitoring, inheriting all the pros it has to offer. With many plugins available in your repository and thousands more in the community-driven Nagios-exchange website, icinga2 is a very good choice for your infrastructure monitoring. I will cover some of the optional features that can be tweaked to suit your needs, once the main configuration has been set up. Some of the points are: Taking full advantage of variables defined in your Host file. Setting up custom scheduled downtimes. Changing the timeout for specific checks. Using a different user for your checks. Writing your own plugin.

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  • Installing PeerVPN with Ansible

    Installing PeerVPN with Ansible

    In addition to the article about the PeerVPN installation and configuration, I will now show you more advanced and quite ‘modern’ way to provision several servers and get your VPN client up really fast. You’ve probably heard of Ansible already. Well, one of its use cases is exactly what we need here: Configuration Manager. Many of us have experienced The Headache, when you need to install, configure and then administer a whole environment. Yes, to repeat the same steps on hundreds of servers, where you have different OS distributions, application versions and all kind of dependencies, and all of that certainly lead to some problems.Well, Ansible is here to help you with all that stuff. You can choose, set and customize anything that is required for specific environment and suit its needs. So, let us start with the introduction to ansible, its structure and components.In my opinion there are two approaches when you first start with Ansible. The first one is to read the official introduction to Ansible, which explains a lot about its structure and then start with simple playbook which you then extend to a role. Or the second one, where you make use of the Ansible Galaxy, which has a lot of community-provided roles open for use. Well not every role is that much scalable and flexible as you want so you can simply combine both approaches, take an already built role and expand its functionalities. If you learn that quick and all of that is boring, you can start building your own Ansible modules.

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  • Levitation in Virtual world or how to convert Xen images to KVM

    Levitation in Virtual world or how to convert Xen images to KVM

    The rule of the "cloud" has already been established and now we have multiple vendors fighting for market share. Many companies started relying on the cloud and seeking more and more automation and could services. It looks easy, you just select a cloud provider, use it's services and you have several virtual machines or containers within minutes. Sounds like magic? Well, Here is the question you are probably asking yourself . What is behind it all? The answer is;  good old virtualization, strong APIs and scripting.   I guess most of you, who are to some extent already familiar with vitualization, and have the affinity to work with opensource technologies have used Xen. It was the very first in the opensource world, and that is for sure. Its first release was in 2002 and it definitely became one of the dominant virtualization solutions in the opensource world. If we take a look at the main vendors like Oracle for example, we will see that behind OVM is again Xen. At the same time lots of companies started using another solution, which you might have heard of - Citrix. The company that created it became very well known.  

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  • Monitoring Openstack Part 1

    Monitoring Openstack Part 1

    Last year we focused on the Openstack technology and the projects behind it. We decided to stress on it and move our scope in that direction because of the rich features and flexibility that it provides. But as we know great power comes with great responsibility.

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  • Containerization with Docker

    Containerization with Docker

    INTRODUCTION TO DOCKER If you have been following the “cloud” trends you probably have heard of Docker. It is an open source implementation of the LXC (Linux Containers) used for packaging an application and its needed dependencies into a container that can be deployed and replaced easily. The containerization in Docker is achieved via resource isolation (cgroups), kernel names spaces (isolating the application’s view of the OS, process trees, etc) and a union-capable file system (such as aufs – mounting multiple directories into one that appears to contain their combined contents). Using containers removes the overhead of having to create, deploy and maintain full VMs for running your applications. As well as providing completely identical PROD, Staging, QA, DEV environments. In some cases you can even move a container from one server to another, making it ideal to spin a quick instance of your PROD environment on a separate server to do a quick test without messing with the actual PROD environment.

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