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Audience And Agenda

Useful for, Developers. Infra Specialists. Dev/Sys Specialists. towards, Understanding what containers and VMs are. Subtle and sound differences between them. It is NOT, Focussed on any DEVOPS tool/technology. Focussed on any particular method/concept. Talking about advanced usage. Some Pre-requisites before you jump in, Idea of VM and Kernel concepts. Basic OS concepts and OSI. The first series of posts is about basics on VM and Container, Let's get started. Next-->
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What Are Containers And VMs ?

What Are Containers And VMs Container Vs VMs: Containers and VM's are similar in their goals. They both eliminate the need for separate physical hardware. They both isolate an application and its dependencies into a self contained unit so that it can run anywhere. The difference is in the how i.e. the architectural Approach VM uses Hypervisor and guest OS, to accomplish it. Container uses name spaces  control groups etc.. to accomplish it. This allows more efficient use of computing resources Both in terms of energy consumption and cost effectiveness. References Used: https://blog.docker.com/2016/03/containers-are-not-vms/ https://blog.mikesir87.io/2017/05/docker-is-not-a-hypervisor/ https://devopscube.com/what-is-docker/ https://medium.freecodecamp.org/a-beginner-friendly-introduction-to-containers-vms-and-docker-79a9e3e119b https://stackoverflow.com/questions/48251703/if-docker-runs-natively-on-windows-then-why-does-it-need-hyper-v <--Previous    

Containers Are Not Vms

Containers Are Not VMs. VM (House) Full OS to Start with and strip away what's needed. Virtualization technology. Everything that sits on a physical Server and pack it in to a single portable binary. Container (Apartment) Start with basic and add what's needed. Application delivery technology. The abstraction is the application, more specifically a service that helps to make up the application. Containerization Basics. Containers are isolated in a host using the two Linux kernel features called namespaces and control groups. Namespaces There are six namespaces in Linux (mnt, IPC, net, usr etc.).  Using these namespaces a container can have its own network interfaces, IP address etc.  Each container will have its own namespace. The processes running inside that namespace will not have any privileges outside its namespace. Control Groups The resources used by a container is managed by Linux control groups.  CPU and memory resource is

Containers In Production

Containers In Production. Questions That Arise: How do i back up my container ?. How do i patch my container ?. Where does my Application Server Run ? What do i do with my existing monolithic apps ?. References Used: https://blog.docker.com/2016/03/containers-are-not-vms/ https://blog.mikesir87.io/2017/05/docker-is-not-a-hypervisor/ https://devopscube.com/what-is-docker/ https://medium.freecodecamp.org/a-beginner-friendly-introduction-to-containers-vms-and-docker-79a9e3e119b https://blog.docker.com/2016/03/containers-are-not-vms/ https://stackoverflow.com/questions/48251703/if-docker-runs-natively-on-windows-then-why-does-it-need-hyper-v <--Previous       Next-->

BackUpContainer

Back Up Of Container. How Do I Backup My Container ? Data does not live on the container. It lives on a named volume that is shared between 1-N containers that you define. Docker recommends named volume for persistent containers i.e direct write to volume outside of container. References Used: https://blog.docker.com/2016/03/containers-are-not-vms/ https://blog.mikesir87.io/2017/05/docker-is-not-a-hypervisor/ https://devopscube.com/what-is-docker/ https://medium.freecodecamp.org/a-beginner-friendly-introduction-to-containers-vms-and-docker-79a9e3e119b https://blog.docker.com/2016/03/containers-are-not-vms/ https://stackoverflow.com/questions/48251703/if-docker-runs-natively-on-windows-then-why-does-it-need-hyper-v <--Previous         Next-->

PatchesInContainer

Patch Management In Container. First let's understand what is in a simple container , Simple Container. Patch Management In Container. Patch Management In Container Do not patch running container. Stop your running container update your docker image. Fire new containers (quickly) from the updated/patched image. A Docker image has two components: the base image and the application image.  Update the base image and then rebuild the application image. . References Used: https://blog.docker.com/2016/03/containers-are-not-vms/ https://blog.mikesir87.io/2017/05/docker-is-not-a-hypervisor/ https://devopscube.com/what-is-docker/ https://medium.freecodecamp.org/a-beginner-friendly-introduction-to-containers-vms-and-docker-79a9e3e119b https://blog.docker.com/2016/03/containers-are-not-vms/ https://stackoverflow.com/questions/48251703/if-docker-runs-natively-on-windows-then-why-does-it-need-hyper-v https://www.logicworks.com/blog/2016/04/docker-securi

Application Server Inside Container

Application Server Inside Container. Where Does My Application Server Run ? Application Server translates in to service run inside a container. Micro-services/container based application will connect to a non-containerized service/application. Standalone servers which execute code give way to one or more containers. Containers provide the same functionality with much less over head and horizontal scaling. References Used: https://blog.docker.com/2016/03/containers-are-not-vms/ https://blog.mikesir87.io/2017/05/docker-is-not-a-hypervisor/ https://devopscube.com/what-is-docker/ https://medium.freecodecamp.org/a-beginner-friendly-introduction-to-containers-vms-and-docker-79a9e3e119b https://blog.docker.com/2016/03/containers-are-not-vms/ https://stackoverflow.com/questions/48251703/if-docker-runs-natively-on-windows-then-why-does-it-need-hyper-v https://www.logicworks.com/blog/2016/04/docker-security-monitor-patch-containers-aws/ https://www.ontrack.com/uk/blog/t