The Emergence of Software and the Internet have both led to industrial transformation, whether it be from shopping to entertainment or banking. Companies these days interact with their customers through the software delivered either as an online service or applications, supported on all sorts of devices. DevOps is a concoction of work practices, ethics and tools designed to increase an organization’s potential to deliver its applications and services faster than conventional software development processes and techniques. Such a combination of practices, providing services at high velocity, evolving and improving products faster aids to better delivery and software development, helping the infrastructure management processes in turn. This work speed enables organizations to serve their customers better and compete more effectively in the open global market. In addition, DevOps helps remove the barriers between siloed and segregated working teams, development and operations and help a whole organization work even better under one roof.
Under a created DevOps model, the development and operations teams work together across the entire software application life cycle, starting from development and test, getting through deployment to its operations. There are a set of key practices that help organizations innovate faster through automating and streamlining their software development and infrastructure management processes when inculcated and accomplished with proper tooling backend. Such practices help organizations adapt to changing markets better and become more efficient at driving business results.
Certain reliability practices like continuous integration and continuous delivery can accordingly ensure the quality of application updates and infrastructural changes to deliver applications while maintaining an optimum experience for end-users reliably. Using a microservice architecture might help make the delivered applications more flexible and enable quicker innovation. The microservices architecture segregates very largely complex systems into simple and independent projects to focus on. The use of monitoring and logging services helps system engineers track deployed applications and infrastructure to react quickly to problems and provide essential services.
What are DevOps Tools?
DevOps tools are certain software services that ensure transparency, automation, and collaboration for organizations to stay at the forefront of the value stream. These tools facilitate effective sharing and exchange of information within the organization and technical know-how between all stakeholders, be it development, operations, security or business teams, for effective product output. The tools help firms resolve most of the challenges faced with the implementation of DevOps practices. However, there is no one solution available that fits all and takes care of everything. Hence, there are a wide variety of DevOps tools available for every requirement. In this article, we will be exploring two DevOps Tools in particular, Ansible and Docker.
What is Ansible?
Ansible is an open-source automation engine that helps in DevOps and comes to the rescue to improve your technological environment’s scalability, consistency, and reliability. It is mainly used for rigorous IT tasks such as configuration management, application deployment, intraservice orchestration, and provisioning. In recent times, Ansible has become the top choice for software automation in many organizations. Automation is one of the most crucial aspects of industries these days. Unfortunately, many IT environments are too complex and often require to be scaled too quickly for system administrators and developers to keep up, rather than manually.
Automation simplifies several complex tasks, making developers’ jobs more manageable and focusing their attention on other tasks and areas that add value to an organization. To sum it up, it frees up time and increases efficiency. Working on Ansible requires no special coding skills and with a very simple set of instructions are necessary to use Ansible’s playbooks. It enables one to model even highly complex IT workflows; the entire application environment can be planned and orchestrated no matter where it’s being deployed. Customization can be set up based on the needs. With Ansible, there is no need to install any other software or firewall ports on the client systems which are to be automated, even no need to set up a separate management structure!. And Because you don’t need to install any extra software, there’s more room for the application resources on the development server.
Features Of Ansible
Some of the most important features that Ansible offers are :
- Configuration Management
- Application Deployment
- Planning & Orchestration
- Security & Compliance
- Cloud Provision
As Ansible is supposedly designed to be very simple to leverage reliability and consistency for configuration management, one with an IT background can quickly get it up and running it. Ansible’s configurations are simple data descriptions of the infrastructure and are readable by humans and parsable by machines. To start the managing systems, all required is a passcode or a Secure Socket Shell network protocol key. For example, suppose one wants to install an updated version for a specific type of software on all the machines present in the enterprise premise. In that case, all one has to do is write out all the IP addresses of remote hosts and write an Ansible playbook to install it on all the host nodes and then run the playbook from the control machine.
Ansible lets one quickly and easily deploy multi-tier apps. There is no need to write a custom code to automate the systems present. Just list the tasks required to be completed by writing a playbook, and Ansible figures it out on how to get the systems to the state you want them to be in. To simplify, there is no need to configure the applications on every machine manually and individually, which would be a rather tedious task. When you run a playbook from the set and configured control machine, Ansible uses Secure Socket Shell to communicate with all remote hosts present within its network environment and run all the set desired commands.
Planning & Orchestration
As the name tells us, orchestration involves bringing the different elements of a delivery pipeline into a beautifully run whole operation similar to a beautifully organized music opera. Knowing each instrument’s role and essence, things are planned around accordingly. For instance, for application deployment, one would need to manage the front-end and back-end services and the databases, networks, storage, etc. You also have to make sure that all the tasks are being handled in the proper order. Ansible helps create automated workflows, provisioning, and to make orchestrating and planning tasks easy. Furthermore, the infrastructure defined in the Ansible playbooks can be used as the same orchestration wherever you need to due to the portability of Ansible playbooks.
Security & Compliance
Applied security policies, such as firewall rules or locking down users, can be implemented and other automated processes present. If security settings are configured on the control machine, and the associated playbook is run, all the remote hosts present will automatically be updated with those settings. So the need to monitor each machine for security compliance manually is eliminated out of the picture. The admin’s user ID and password are not retrievable in plain text on Ansible for extra security.
The first step in automating an applications’ life cycle is automating the infrastructure. With Ansible, you can plan your cloud platforms, virtualized hosts, network devices, and bare-metal servers.
The Ansible Architecture
Ansible’s Architecture comprises of the following components :
- Module: Small programs that Ansible uses to send out from a control machine to all the nodes or remote hosts. The modules are executed altogether using playbooks, and they control things such as services, packages, and files.
- Plugins: Ansible comes with a number of its plugins, which are extra pieces of code that augment functionality.
- Inventories: From the registered inventory, you can assign variables to any of the hosts using a simple text file, where the information of all the IP addresses, databases, servers is present.
- Playbooks: Describe the tasks that are to be given priority and without the need for the user to know or remember any particular syntax. Playbooks are instruction manuals for tasks.
- APIs: Application programming interfaces available help extend Ansible’s connection types, callbacks, and more.
Some of the widely used basic Ansible Commands are as follows :
To Verify connectivity of host: # ansible <group> -m -ping To Reboot the host systems: #ansible <group> -a “/sbin/reboot” Create a new user: # ansible <group> -m user -a “name=ansible password=<encrypted password>” Delete a user: # ansible <group> -m user -a “name=ansible state=absent” To perform File Transfer to more than one server : # Ansible abc -m copy -a “src = /etc/yum.conf dest = /tmp/yum.conf” To Reboot more than one server : # Ansible abc -a “/sbin/reboot” -f 12
How Does It Work?
Ansible works by connecting to your server with Secure Socket Shell protocol and hereby pushing out smaller programs known as the Ansible modules. Ansible’s most powerful feature while creating playbooks is the containment of YAML code. As a result, users can program repetitive tasks automatically, i.e. automate without learning an advanced programming language.
What is Docker?
Docker is an open-source platform application for developing, shipping, and running applications. It enables developers to package applications into containers, a set of standardized and executable components that combine the application source code with the operating system libraries and dependencies required to run that code in an executable environment. Containers can even be created without Docker, but the platform and user interface make it easier, simpler, and safer to build, deploy and manage containers. Docker enables developers to perform operations such as build, deploy, run, update, and stop on containers using simple commands and work-saving automation through a single API. In addition, Docker enables you to separate the created applications from the present infrastructure to help deliver the software quickly. Using Docker, infrastructure can be managed similarly to manage applications. Implementing Docker’s methodologies for shipping, testing, and deploying code quickly, significantly reduces the delay between writing code and running it into production.
Docker provides the tooling and a platform to manage the lifecycle of created containers:
- Application and its supporting components can be developed using containers.
- The container hence becomes the unit for distributing and testing metrics of your application.
- The application can then be deployed into the production environment as a container or an orchestrated service. Works the same even if your production environment is a local data centre, a cloud provider or a hybrid of the two.
Features Of Docker
Some important features of Docker are :
- Application isolation: Docker provides containers that can be used to run applications in an isolated environment. Since each container is independent of one another, Docker can execute any kind of application as defined.
- Swarm: Swarm, a clustering and scheduling tool for Docker containers, uses the Docker API on the front end, making it easy to use with various tools to control it. It comprises a self-organising group of engines that enables pluggable backends.
- Security Management: It saves important code elements directly into the swarm and chooses to give services access to only certain protocols, including a few important commands to the engine such as secret inspect, secret create, etc.
- Software-defined networking: Docker supports Software-defined networking, and hence without having to touch a single router, the Docker CLI and Engine enables users to define isolated networks for containers. Operators and Developers can design systems with complex network topologies and define the networks into the configuration files.
- Ability to Reduce the Size: Since it provides smaller footprints of the OS via containers, Docker can help to reduce the size of the current development.
The Docker Architecture
Docker uses a client-server architecture where the Docker client communicates to the Docker daemon, which performs several heavy processing tasks such as building, running, and distributing the created Docker containers. The Docker client and daemon can run on the same system, or the Docker client can be connected to a remote Docker daemon. The Docker client and daemon communicate using a REST API over UNIX sockets or a network interface. Another Docker client is Docker Compose, which lets you work with applications consisting of a set of containers.
The Docker daemon
The Docker daemon known as dockerd listens for the Docker API requests and manages several Docker objects such as images, containers, networks and volumes. To manage Docker services, a particular daemon can also communicate with other daemons.
The Docker client
The Docker client docker provides the communication pathway the way through which many users interact with Docker. Commands such as docker run, to execute the docker are sent by the client to dockerd, which executes them through. The docker command uses the Docker API. The Docker client can communicate with more than one daemon.
A Docker registry stores all the relative Docker images. Docker Hub is a public registry that anyone can use and access, and Docker is configured in a certain way to look for images on Docker Hub by default. Private registries can be created and run. When commands such as docker pull or docker run are executed, templates with instructions known as images are pulled from the configured registry. With the docker push command, your image is pushed to your configured registry.
When you use Docker, you create and simultaneously use images, containers, networks, volumes, plugins, and other objects.
The two of the most important docker objects are :
An image in a Docker is a read-only template with instructions for creating a new Docker container. Most of the time, an image template is based on another image, with some additional customizations. One may build an image based on the Ubuntu image, but install the apparent Apache web server and the configuration details needed to make the application run on the system. One can create his own image or simply use those created by others and published into a registry. To build an image, create a Dockerfile with a simple syntax that defines the steps needed to create the image and run it. Each instruction present in the Dockerfile creates a layer in the image. When a Dockerfile is changed or the image is rebuilt, only those layers which have changed are rebuilt. This makes using images so lightweight, small, and fast compared to other similar virtualization technologies.
A container is a runnable instance defined by the docker image. You can perform operations such as create, start, stop, move, or delete a container using the Docker API or CLI. A single container can be connected to one or more networks; storage can be attached to it or create a new image based on its current state. Generally, a container is relatively well isolated from other containers and its host machine for security. Container’s network, storage, or other underlying subsystems and how isolated they remain from other containers or the host machine can be defined and controlled. A container is defined by its image and other configurations set and provided by the user when creating or starting it. When a container is removed or deleted, any changes to its state that are not saved and stored in persistent storage disappear automatically.
Some of the basic and widely used commands for Docker are as follows :
To know the Docker Version: ~$ docker --version To pull information using docker images: ~$ docker pull ubuntu Create a container: ~$ docker run -it -d ubuntu Get a list of running Containers: ~$ docker ps -a Access a running Container: ~$ docker exec -it <Container name> To stop a running Container: ~$ docker stop <Container name> Shutting down a Container completely : ~$ docker login
Where can Docker Be Used?
- To Deploy highly available, fully managed Kubernetes clusters.
- To Deploy and run apps across on-premises, edge computing and public cloud environments using a cloud service.
- Simplify and consolidate the data lakes across the organization by seamlessly deploying container-enabled enterprise storage.
- Docker Compose can be used to manage the application’s architecture.
Both Docker and Ansible provide a wide array of uses and can be integrated according to the requirements and needs. For example, one makes use of modules, while the other makes use of containers to convey or store information. In addition, both the DevOps tools can be used to create automation services across the enterprise with their unique set of properties and capabilities.