For a recent project using Ansible to define and run KVM virtual machines, I had to debug an issue with cloud-init. This was a trigger for me to do a bit of research on how cloud-init operates, and I decided to share my findings in this post. Note that this post is not an instruction … Continue reading Understanding cloud-init
In this post, we will learn how to set up VXLAN overlay networks as tenant networks in Neutron and explore the resulting configuration on our compute nodes. Tenant networks The networks that we have used so far have been provider networks - they have been created by an administrator, specifying the link to the physical … Continue reading OpenStack Neutron – building VXLAN overlay networks with OVS
In this post, we will go through the installation of Neutron for flat networks and get to know the basic configuration options for the various Neutron components, thus completing our first fully working OpenStack installation. If you have not already read my previous post describing some of the key concepts behind Neutron, I advise you … Continue reading OpenStack Neutron installation – basic setup and our first instances
In this post, we will look into Nova, the cloud fabric component of OpenStack. We will see how Nova is installed and go briefly through the individual components and Nova services. Overview Before getting into the installation process, let us briefly discuss the various components of Nova on the controller and compute nodes. First, there … Continue reading OpenStack Nova – installation and overview
Apart from Keystone, Glance and Placement are two additional infrastructure services that are part of every OpenStack installation. While Glance is responsible for storing and maintaining disk images, Placement (formerly part of Nova) is keeping track of resources and allocation in a cluster. Glance installation Before we get into the actual installation process, let us … Continue reading OpenStack supporting services – Glance and Placement
Over time, I have worked with a couple of different commercial cloud platforms like AWS, DigitalOcean, GCP, Paperspace or Packet.net. Even though these platforms are rather well documented, there comes a point where you would like to have more insights into the inner workings of a cloud platform. Unfortunately, not too many of use have … Continue reading Building your own cloud with OpenStack – overview
When you browse the module list of Ansible, you will find that the by far largest section is the list of cloud modules, i.e. modules to interact with a cloud environments to define, provision and maintain objects like virtual machines, networks, firewalls or storage. These modules make it easy to access the APIs of virtually … Continue reading Automating provisioning with Ansible – building cloud environments
In the previous post, we have learned the basics of Ansible and how to use Ansible to execute a command - represented by a module - on a group of remote hosts. In this post, we will look into some useful modules in a bit more detail and learn a bit more on idempotency and … Continue reading Automating provisioning with Ansible – using modules
For my projects, I often need a clean Linux box with a defined state which I can use to play around and, if a make a mistake, simply dump it again. Of course, I use a cloud environment for this purpose. However, I often find myself logging into one of these newly created machines to … Continue reading Automating provisioning with Ansible – the basics
So far I have mostly used Amazons EKS platform for my posts on Kubernetes. However, this is of course not the only choice - there are many other providers that offer Kubernetes in a cloud environment. One of them which is explicitly targeting developers is DigitalOcean. In this post, I will show you how easy … Continue reading Automating cluster creation on DigitalOcean
