In the simplest terms, a container is a “wrapper” that allows software to travel between operating environments. Container technology greatly speeds and enhances cloud computing development.
Cloud computing companies hail containers as a powerful tool for developing, managing and migrating applications and software components from one system or environment to another.
Containers create a unique virtual space – called a “sandbox” – that separates an application from others in the same environment. This abstraction process ensures that the software code doesn’t connect to other virtualized spaces and systems. Containers typically provide a library of content and tools, usually available via a toolbar. Containers and microservices often work together.
Containers are deployed in one of two ways: by creating an image inside a container, or using a pre-made image.
They are different than virtual machine workloads, which may run several operating systems on the same computing node but do not virtualize the OS itself. Because containers virtualize the OS, they do not use a hypervisor. Instead, they use a kernel and a daemon that manages the compartmentalization between containers.
It’s important for organizations to weigh cloud containers versus virtual machines. In some cases, containers may not provide required functionality because of their dependency on a host or server running a specific OS. They can also be affected by vulnerabilities in the OS kernel.
Key Tasks Performed by Containers
Along with open source Kubernetes or another orchestration platform, organizations can address a number of important tasks using containers. For example:
- It’s possible to develop software on a desktop or laptop and transfer the application and data to a test environment.
- Developers and IT staff can often move applications from one cloud platform to another without disruption.
- Organizations can migrate applications and data from a physical computing device such as a PC or Mac laptop to a virtual machine running (VM) in a public or private cloud.
- Containers simplify moving applications from a production environment to a service environment.
- During development or testing, an application crash or container that fails will affect only the specific container the code resides in rather than other applications or the entire VM. This allows a service to continue operating without a noticeable impact.
- Cloud containers have grown enormously in popularity since Docker introduced a platform in 2013. According to 451 Research, the application container market is projected to grow from $762 million in 2016 to $2.7 billion by 2020.
A Forrester report from Q4 2018 noted that 58 percent of developers report that their companies currently use containers or plan to use containers in the next 12 months.
Benefits of Containers
Along with the many tasks they perform, containers and microservices offer a number of compelling benefits to enterprise environments:
- A major argument for containers in the clouds versus virtual machines debate is they consume relatively small amounts of disk space and memory.
- Because these components virtualize applications in specific “containers,” they create an isolation boundary at the application level. This means that if a crash, breakdown or security breach occurs within a container, the virtual machine and other applications aren’t affected.
- Similarly, because containers remain isolated from one another, other applications and software running on the same OS or virtual machine are not impacted by bugs and compatibility issues.
- Cloud containers are highly flexible and portable. They can be moved, scaled and reorganized quickly to match changing needs of teams and an enterprise. This also makes it easier for developers to test software across multiple environments.
- Users, including development teams, can cluster multiple containers and create microservices that allow these groups to update any application individually rather than pulling the entire group of applications offline for an update.
- Cloud containers often reduce costs by streamlining workflows, reducing downtime, and reducing the impact of a bug or breach.
How Containers Aid in Cloud Deployments
Containers are a natural fit for many organizations with development teams deploying applications into the cloud. Among the benefits:
- Developers can make tweaks, adjustments and updates – and deploy the new or updated software as quickly as they complete the changes. This speed increase, as well as the ability to populate the update across systems, is critical within cloud frameworks.
- Cloud containers and microservices create a consistent and predictable environment, along with familiar tools and resources. Consequently, tasks such as debugging code and diagnosing errors are greatly reduced, regardless of where the application resides. Developers can spend more time on productive tasks, including adding and improving features in software.
- As organizations look to boost speed, often through DevOps and other agile development frameworks, a “run anywhere” approach is critical. Regardless of the operating system, programming language or environment in which the application will run, containers deliver an approach and framework that does not vary across environments. This includes bare metal, clouds, different operating systems and devices.
As organizations look to improve processes and innovate, it’s important to reduce overhead that results from manual and inefficient processes. A big benefit of containers is the ability to automate and orchestrate numerous tasks.
Today, container management software products from companies like Amazon Web Services, Google Cloud and Microsoft Azure allow developers to orchestrate and extend containers into the cloud. These gains revolve around key areas:
- Automated rollouts and roll backs. Updates and changes take place without the need for constant oversight and involvement. Staff can devote more time to software improvements and innovation.
- Health monitoring. Container orchestration tools can spot bad code and prevent it from being deployed. They also can monitor systems and applications – and restart containers that stall or crash.
- Automatic scaling of services. A big advantage of the cloud is the ability to scale. Container services make it easier to dynamically adjust and adapt to changing needs, including utilization.
- Management. Containers allow an organization to declaratively manage resources, including what resources are replicated and retired.
- Flexibility. It’s possible to deploy containers anywhere, including hybrid deployments that involve different operating systems, systems and clouds.
Containers and DevOps
Containers make it easier to produce and host applications inside portable environments. DevOps establishes a framework for developing software faster and in a more iterative way. These two approaches are a good fit for one another because, together, they allow organizations to produce and update software code in a more streamlined and efficient manner—while improving security.
There are three major benefits to combining containers and DevOps.
- A more robust development framework. Containers simplify and automate many of the tasks involved with DevOps. They eliminate numerous manual processes, reduce errors and, ultimately speed development and deployment.
- Streamlined updates. DevOps is all about iterative and incremental updates. Containers make it much easier to achieve goals surrounding speed and quality metrics by providing microservices. It’s possible to handle tasks and address problems in containers without disrupting the overall flow of development.
- Support across platforms and frameworks. Today, organizations support multiple software programming languages, operating systems, cloud services and devices. Containers serve as a bridge because they are agnostic and work across different environments. In some cases, it’s also possible to move a container from one environment to another.
Future of containers and cloud computing
Containers continue to advance rapidly, fueled by the growth of cloud computing. Expect container technology to add a more robust feature set of capabilities, and perhaps an artificial intelligence component.
In software development around containers, there’s a growing focus on using more modular and flexible approach, including DevOps. In the coming years, it’s likely that these tools will gain a still larger community of developers working on them – making them that much more powerful.
Likewise, orchestration tools such as Docker, Amazon ECS, Google and Azure Container Service continue to gain features, including advances in Kubernetes. As these environments march forward, it’s nearly certain that containers, microservices and cloud computing will become more intertwined and intrenched with operational trends and business goals.