Devops

Continuous integration is a software development approach where developers regularly merge or integrate code changes into a central repository. Automated builds and tests are then run from the shared repository, immediately surfacing any functional or integration errors. In the past, developers often worked in isolation for extended periods, merging code changes only after their work was completed. Merging long-accumulated code changes was difficult, time-consuming and laden with bugs. With continuous integration, developers frequently merge changes to a shared repository using a version control system. Every revision committed to the repository triggers an automated build and test.

Continuous integration usually refers to the build and unit testing stages of the DevOps software process. The goals of continuous integration are to find and address errors quickly, improve software quality, and accelerate the validation and release of new software updates. This iterative building and testing process overcomes many problems that formerly occurred between the planning, design and implementation stages in the software development lifecycle. Regular merging of various team member’s code prevents software projects from drifting too far from a functional state. As new code is added by others, catastrophic merge conflicts can be avoided. With continuous integration, when developers check in bad code the system automatically notifies the entire team within minutes. This prevents new versions from accidentally building upon or relying on bad code.

Continuous integration ensures bugs are caught early in the development cycle, which makes them less expensive to fix. It also reduces the time to market for new applications and helps businesses respond quickly to changing customer needs. Open source technologies and development tools can support continuous integration and the DevOps model with automation and lifecycle management products. For example, SUSE Manager includes automated deployment and configuration tools for software development projects.

Continuous delivery is an iterative software development approach that ensures every change to a system can be released. The goal is to make software releases reliable so organizations can deliver them frequently, reduce risks, get faster feedback from end users, and shorten time-to-market for innovations. In continuous delivery, every code change is built, tested and then pushed to a non-production testing or staging environment. There can be multiple and parallel test stages before a production deployment. Tests may include user interface testing, load testing, integration testing, API reliability testing and others.

Continuous delivery lets developers automate testing so they can verify application updates across multiple dimensions before deploying the software to customers. Every revision triggers an automated flow that builds, tests and then stages the update. The final decision to deploy to a live production environment is triggered by the developer. Automated testing helps developers validate updates and discover any issues with the changes. With frequent, automated testing developers can discover and address bugs early in the product development process, before they create problems.

Continuous delivery lets developers more easily perform additional types of tests on their code because the process is automated. Cloud computing allows development teams to cost-effectively automate the creation and replication of multiple testing environments without affecting the on-premises environment. Open source technologies and development tools support continuous delivery with automation and lifecycle management products.

DevOps (a combination of “development” and “operations”) is a software application and services development model that integrates development lifecycles with agile operations. In practice, development and operations engineers participate together in the entire DevOps lifecycle, from design and development to production and support.

DevOps emphasizes communication and collaboration between the traditionally separate developer and IT operations teams. DevOps promotes automation and monitoring throughout the software lifecycle, aiming for shorter development cycles, increased deployment frequency, more dependable releases, and closer alignment with business objectives. DevOps practices are intended to reduce the time between changing a system and putting that change into normal production, while ensuring high quality. In line with the lifecycle process, many DevOps tools fall into one or more of these categories: Plan, Code, Build, Test, Release, Deploy, Operate and Monitor.

Working together as one team or department, DevOps can help an organization deploy software more frequently while maintaining service stability. In a software-defined infrastructure, DevOps methodologies are critical. Application containers can bring developers and operations engineers closer together by providing a shared resource for continuous integration and continuous delivery. Containers also facilitate the Build step of the DevOps lifecycle. By design, containers are easy to scale and can support the growth of new business applications. Open source technologies and development tools support the DevOps model with automation and lifecycle management products.