Docker containers provide functionality similar to that of virtual machines (VMs) but are far more light weight as they occupy far less space on the host machine. Since its inception in 2013, the open source Docker engine has been one of the most impactful innovations in IT. Worldwide, over 13 million developers currently rely on Docker’s lightweight PaaS technology to facilitate speedy, scalable container-based development.
It’s easy to see the appeal. Why spend hours on repetitive configurations and complex troubleshooting when you can unlock better results with more flexibility with Docker? As a testament to this ability to optimize the development lifecycle, the platform was recently named the most loved and most wanted developer tool in Stack Overflow’s 2022 Developer Survey. This has led to a massive influx of developers looking for ways to level up their platform-specific skills and competencies.
The first step to mastering Docker is understanding how containerization has changed the way applications are developed and deployed. Before doing that, you need to know what containers are and what they do.
Here’s a quick breakdown to make things easier.
What are containers and how do they work?
Think of the contents of your refrigerator. Most store-bought items come covered in some form of packaging while leftover meals are typically packed away in containers. This keeps food isolated and stops things that aren’t supposed to mix together from doing so. The containers we’re talking about in IT might be a bit more complicated, but the same basic logic applies.
In traditional development environments, you have the computer hardware and the operating system. This is the fridge. Branching out from that, you have a variety of software applications and frameworks, each with its own libraries and dependencies. This is fine when everything is running smoothly, but what happens when there’s a conflict between the dependencies of different applications? What happens if two applications require access to different versions of the same library?
This leads to dependency matrix hell and makes it incredibly difficult to maintain and upgrade your technology. Fortunately, with the help of powerful container engines like Docker, containers provide a ready-made solution for this mess. Just like the containers in your fridge stop spaghetti noodles from mixing with chow mein noodles, the containers in your tech stack stop your MySQL library from mixing with your React library.
Essentially, containers act as a conduit that connects your hardware and OS to individual applications. The application is stored along with its libraries and dependencies, making it easy to move the application between different virtual machines and computer systems across environments without impacting core functionalities or other software. Containers isolate everything that the application needs to run smoothly.
Key advantages of containerized app development:
Speedy application installations
In a traditional development ecosystem, installing new applications is a time-consuming, involved process. Developers need to check multiple dependencies and troubleshoot conflicts that arise between the new application and existing software. This check-off process needs to be repeated every time you install the application. With containers, the application comes packaged with its required libraries and dependencies. Conflict-free installation can be achieved quickly by running a single command. Speaking of conflicts…
Escape from dependency hell
Traditional development often leads to a complex, convoluted matrix where different applications require different versions of the same libraries and dependencies. This can be chaotic to resolve and makes speedy, scalable development increasingly difficult. By using a tool like Docker to package all the dependencies into a container alongside the application, developers can alleviate this time-consuming issue and focus on coding.Easily move applications between systems
Modern development often requires you to move applications between different environments, like a developer’s laptop and a production enterprise system. Without containers, packaging and moving software is an arduous and error-prone task. Containers simplify the process significantly. Containers are also helpful when shipping new applications, as they allow you to seamlessly transition through different stages of development without duplications or compatibility issues.
Isolate and identify key processes
In a traditional development environment, there are lots of interrelated moving parts. When things go wrong, it can be challenging to identify the precise cause of the issue and respond accordingly. On the flip side, containers isolate applications and their related libraries and dependencies. This makes it easy to diagnose issues and implement the appropriate solution rapidly and securely.Rapid, flexible scalability
One of the major drawbacks to the traditional deployment model is the difficulty that ensues when trying to scale. The process is time-consuming, stressful, and not particularly user-friendly. With containers, the opposite is true. Leveraging a load balancer to split traffic, developers can quickly and confidently scale the applications horizontally using independent containers. Here’s how Docker fits into the equation
With the ability to package applications into containers that run on any Linux, Windows or Mac computer, Docker is widely used for both on-premises and cloud native development. It is recognized throughout the industry as one of the best ways to capitalize on the benefits outlined above.
For aspiring or current developers, learning best practices for Docker container deployment is a great way to stand out from the crowd when applying for in-demand positions. It’s also a great way to teach yourself how to efficiently manage and scale powerful cloud native applications and use containers to your advantage.
6 great reasons to learn Docker best practices
- Docker simplifies app containerization. The general advantages of containers outlined above are not created in a vacuum. Standardizing your operations with Docker enables you to tap into these benefits, seamlessly move between on-premises and cloud development environments and ship tested, secure applications quickly.
- Docker has a massive open-source community. Though Docker’s robust online community is great for troubleshooting issues and accessing on-demand support, the real benefit occurs within the Docker Hub. This massive online collection of Docker container images makes it easy to collaborate with your team or with community developers.
- Docker supports accelerated app development. Docker helps throughout all stages of development. It has tools for building your own unique applications and container images, tools for sharing these container images with the community and tools for running multiple applications across different on-premise and cloud native environments.
- Docker works with your favorite platforms and tools. It doesn’t matter whether you’re coding applications for AWS, Azure or GCP, Docker’s flexible containers have multi-platform functionality. Docker is also compatible with Kubernetes, GitLab, MongoDB, and countless other leading development tools.
- Docker is widely used across many different industries. Major organizations—including Pinterest, Spotify, and Twitter—rely on Docker containerization for application development, but even that doesn’t do justice to how widely deployed this technology truly is: the list covers telecom giants, streaming services, Ivy League universities, and more.
- Docker opens the door to new job opportunities. Docker’s widespread use across multiple industries means that a lot of companies are looking for employees with skills on the platform. Demonstrating proven proficiency can help launch your resume to the top of the pile.