Docker Training in Hyderabad | Docker Training

1. Docker Training in Hyderabad | Docker Training What is Docker? There are two ways of looking at Docker . The first approach involves seeing Docker containers as really lightweight virtual machines, while the second approach is to see Docker as a software packaging and delivery platform. This latter approach has proven a lot more helpful to human developers and resulted in widespread adoption of the technology. An Overview of Docker Containers Traditionally, cloud service providers used virtual machines to isolate running applications from one another. A hypervisor, or host operating system, provides virtual CPU, memory and other resources to many guest operating systems. Each guest OS works as if it is running on an actual physical hardware and it is, ideally, unaware of other guests running on the same physical server. However there are several problems with virtualization. First, the provisioning of resources takes time. Each virtual disk image is large and bulky and getting a VM ready for use can take up to a minute. Second and a more important issue system resources are used inefficiently. OS kernels are control freaks that want to manage everything that’s supposedly available to them. So when a guest OS thinks 2GB of memory is available to it, it takes control of that memory even if the applications running on that OS uses only half of it. On the other hand, when we run containerized applications, we virtualize the operating system itself, not the hardware. Now, instead of providing virtual hardware to a VM, you provide a virtual OS to your application. You can run multiple applications and impose limitations on their resource utilization if you want, and each application will run oblivious to the hundreds of other containers it is running alongside. Docker as a Developer’s Tool One of the problems developers often deal with is the difference between the production server, where the applications run, and their own dev machines (usually laptops and workstations), where applications are developed. Let’s imagine you have Windows 10 running on your desktop but you want to write applications for Ubuntu 18.04. Maybe you are using Python v3.6 to write your application, while the Ubuntu server is still running at 3.4. There are just too many variables to take into account and so we use Docker to abstract that complexity away. Docker can be installed on any OS even Windows and Mac OS X are well-supported. So you can package your code into a Docker image,run and test it locally using Docker to guaranteed that the containers that were created from that Docker image will behave the same way in production.

2. Note: All the dependencies, such as the version of programming language, standard library, etc., are all contained within that image. This way of looking at Docker images as a software package has led to the following popular quote Docker will do to apt what apt did to tar. Apt, the package manager still uses tar under the hood, but users never have to worry about it. Similarly, while using Docker we never have to worry about the package manager, although it is present. Even when developing on top of Node.js technology, for example, developers prefer building their Docker images on top of Node’s official Docker image. So, that’s a brief overview of what’s Docker and why one might want to know about it even if they are not involved in DevOps. DevOps Online Hub provides Docker and Kubernetes Online Training and 41 Career Building Course Videos by experienced trainers. All the class recordings, presentations will be shared with you for reference. For More Details Call Us: +91 9676446666 * Live Instructor-Led Online Classes delivered by experts from the industry. * Get Real-time exposure of the technology. * All the class recordings, presentations will be shared with you for reference.