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  • Icinga 2 - monitor AWS EC2 instances dynamically

    Icinga 2 - monitor AWS EC2 instances dynamically

    Now days it is a challenge to monitor instances which are created/deleted on the fly (instances in auto scaling group for example), so how we could accomplish this with Icinga 2? Well, in this blog we will provide some hints, how to have such configuration without writing complicated AWS CLI/API calls or lambda functions, but configuring mainly icinga.

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  • High availability (Multi-master) Kubernetes cluster hosted on AWS

    High availability (Multi-master) Kubernetes cluster hosted on AWS

        This is a first post of a mini-series dedicated to running Kubernetes hosted on AWS. First post will be about the considerations we have made when proposing production ready and Enterprise grade Kubernetes environment to our clients. I will go more technical, with the tools and AWS services we are using, in the next blog post, here I will try to cover what problems we are solving.     High availability is a characteristic we want our system to have. We aim to ensure an agreed level of operational performance (uptime) for a higher than normal period. These are the principles we follow when doing the system design:  - Elimination of single points of failure. This means adding redundancy to the system so that failure of a component does not mean failure of the entire system.  - Reliable crossover. In redundant systems, the crossover point itself tends to become a single point of failure. Reliable systems must provide for reliable crossover.  - Detection of failures as they occur. If the two principles above are observed, then a user may never see a failure. But the maintenance activity must.        Below graph shows the Kubernetes Master components used for setting up a cluster. Will go thorough them one by one :

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  • 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 2

    Monitoring Openstack Part 2

    In my previous blogpost I was discussing how to monitor RabbitMQ as a centralized message Q of Openstack. Well, that's quite important but the end goal of having cloud are the instance on top of the machine. Most of you and especially the infrastructure guys who dig into monitoring will know what are the most important components to look over.The reason to monitor is to have reasonable planning which is probably the drill in cloud environment where you have spawnlarge number of virtual machines of containers. On the other hand having the data in one glance is very easy to increase the reliability, uptime plan better your architecture and identify the bottlenecks of your setup.

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  • Oracle Database – Monitor with nagios using check oracle health

    Oracle Database – Monitor with nagios using check oracle health

    This tutorial explains how to set-up the check_oracle_health script (credits to Gerhard Lausser) to work on your Nagios environment on CentOS (or any RedHat based Linux). This nagios plugin allows to monitor many oracle DB parameters – like tablespaces size, session, process count, SGA pool etc. Check it out on the author’s webset.The hardest part of the setup is installing the dependent perl libraries and making modifications in the perl code for them to work.On oracle server we need to create the monitoring user and grant rights, only the minimum necessary for the script to work.

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  • MQ Part 1 - Introduction to message oriented middleware and IBM MQ

    MQ Part 1 - Introduction to message oriented middleware and IBM MQ

      Message Oriented Middleware (MOM) MOM is а connectivity software that consists of a set of services that allow multiple applications running on one or more machines to interact across a network. Message queuing applications use asynchronous processing to send and receive messages. They read and operate on the messages independently. In its simplest form a message sent from an application to another application will look like something like this : There are many implementations of this functionality, some are Open Source and some are proprietary. A few examples are IBM MQSeries, Apache ActiveMQ, RabbitM, Kafka, etc. In this article we will go in more detail about IBM MQ since it is the most widely adopted implementation in the Enterprise.

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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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  • ITGix is starting its own DevOps platform!

    ITGix is starting its own DevOps platform!

    ITGix is proud to announce the start of our innovative DevOps Platform. It aims to enable companies integrate latest DevOps practices in their environments, while keeping everything in well organized and automated manner.

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