The D2C Knowledgebase

  • Extending Ansible – plugins, part 2

    Under the hood of d2c.io service we use Ansible a lot: from cloud VM creation and provisioning to Docker containers and user apps orchestration. In the previous article we made an overview of plugin types supported by Ansible and created several own plugins: test, filter, action and callback. In this article we will dive deeper… Константин Суворов …
  • Extending Ansible – plugins, part 1

    Under the hood of d2c.io service we use Ansible a lot: from cloud VM creation and provisioning to Docker containers and user apps orchestration. Ansible is very flexible by its nature. It is written in Python and has modular design – you can easily extend functionality with custom plugins and modules. Plugins add new functions or change …
  • HAProxy load balancer. Part 2: Backend section and the algorithms

    This is the second article about HAProxy. The last one was about basic terms and layers. Here I’m going to tell you about balancing algorithms. The backend section of the configuration file is responsible for the balancing algorithm. Haproxy has 9 algorithms. Roundrobin The first in the list and the simplest algorithm is Round Robin. You …
  • Introduction in highload: basic principles of building IT-infrastructure

    Let’s say you have a working website. The load has increased, and shared hosting can not take the load. Then you have migrated your web app on VDS, but it can not take the load too. Next, you need to do something. And what to do next is my article about. #Testing You can not …
  • Speed up Ansible

    Under the hood of d2c.io service we use Ansible a lot: from cloud VM creation and provisioning to Docker containers and user apps orchestration. Ansible is a convenient tool that doesn’t require complex setup because of it agentless nature. You don’t need to preinstall any software (agents) on managed hosts. In most cases, you would …
  • How does our PaaS make the developer’s life easier

    Probably, it was necessary to start the knowledge base from this article, which would tell about D2C and about the tasks that the platform helps to solve. But this thought came to my mind just a couple of days ago. And I wrote the article. Why do you need D2C A fast-growing and constantly evolving …
  • HAProxy Load Balancer. Part 1: basic terms and layers

    It is the first article from the cycle about HAProxy. Here I’m going to explain basic terms and existing layers of load balancing. Summary So if the load has been increased you have two ways: add resources on a server or add more servers and join them to the cluster. Both ways could help to …
  • Scalable WordPress with NGINX and smart Varnish caching

    Telling about how to construct a stack to get fast and scalable WordPress using Varnish reverse cache, NGINX and load balancer. Summary WordPress architecture made flexible for a huge dev community. This is why so easy to extend it but so bad in a case of performance. To render a page WordPress has to go …
  • Creating Varnish service from not an official Docker Image

    Let’s review the case when an app has not an official Docker Image, and you want to create your own from scratch. For example famous cache-proxy service Varnish. 1. Go into your D2C account at https://panel.d2c.io, click “Create project” on dashboard 2. Click “Create service“ 3. Choose “Docker“ Denis Zaripov Product manager 3. Specify Docker Image as …
  • Deploying Jenkins from an official Docker Image

    Let’s take an open-source automation server Jenkins and Deploy it from an official Docker image. 1. Go into your D2C account at https://panel.d2c.io, click “Create project” on dashboard 2. Click “Create service“ 3. Choose “Docker“ Denis Zaripov Product manager 4. Specify Docker Image as “jenkins“, version “latest“. 5. Add Persistent data volume /var/jenkins_home 6. Add 8080 and 50000 …
  • Scalable WordPress with Master-Slave database

    Showing how to deploy a scalable wordpress CMS with MasterSlave database and loadbalancer