Containerization helps developers and organizations create, ship, and run applications—containers house everything an application needs to run on a system that hosts the container technology. Besides, containers provide a simple way of isolating services, components and applications. These behave like virtual machines with the advantage of not interfering with the surrounding processes.
Even though containers are valuable in the current software development trends, realizing containerized deployments in organizations is not easy. This article outlines five best practices for containerized deployments.
Importance of using containers
According to Forbes, businesses are embracing containerization to accelerate software development and digital transformation. Developers rely on containers to standardize the way they develop, package, deploy and manage applications. It is easy to redeploy a service in a certain configuration using containers. Containers allow reproducibility and make it easy to archive configurations, tear down and rapidly deploy services. The adoption of containers in organizations can result in lower development, deployment and testing costs.
Maintenance costs may also decrease considerably with time through the use of well-built and maintained containers. Through isolation and allowing multiple applications to run concurrently, containerization can ease the application development lifecycle, promote security and reliability while at the same time making the system less vulnerable to configuration errors. What’s more, containerization makes system administration simpler. The responsibility for software dependencies moves from system administrators to container developers.
Today, containers effectively bundle applications, dependencies, configurations and related libraries in a package capable of deploying across various environments. Containers ease reproducibility and reliability associated with build-time and runtime. Rather than each application user building the environment, the container encapsulates everything to avoid library mismatches.
As well, developers can develop and run containers on various host environments. Compared to virtual machines, containers are lighter, allowing for efficient use of hardware and better use of the current hardware.
Best practices for containerized deployments
Containers are not inherently secure, so some concerns should be addressed proactively.
1. Container Scanning
Through container scanning, developers have an efficient way of ensuring containers are secure. There are various ways vulnerabilities find their way into containers. Vulnerabilities could arise from interactions with adjacent containers and the host operating system, storage and networking configurations, among others. A container scanner is an automatic tool that evaluates various container elements to establish security vulnerabilities.
Besides that, vulnerabilities can arise from the code and tool added to an image. As well, issues may originate from other images (parent images) that the container relies on. So, the image could be running on a public image with known vulnerabilities. It is common when developers do not download images from verified publishers and fail to authenticate image contents and publishers.
Also, images from trusted and well-known publishers often have vulnerabilities. By scanning images for vulnerabilities and establishing the parent images vulnerabilities, developers can remediate many issues. Integration of security scanners can occur in various phases of development. For instance, developers can scan potential parent images before choosing one to be the base image.
Also, scanning container registries offers an opportunity to decrease the number of vulnerabilities across various images often used in organizations. It is also possible to scan stored images to establish any new vulnerability in the existing images. This way, developers can avoid deploying such images in future productions.
2. Taking Security into Account From the Onset
Most consider isolating containers to bolster their security. Isolation in containerized environments only isolates resources and should not be taken as the main security measure that replaces other techniques. Besides, isolation in some cases can pose threats. For instance, failure to properly secure a container runtime can compromise the container providing an entrance for malicious activities. So, container hardening should be part of the development process before deployment.
Early and proactive security considerations can help decrease risk. As highlighted above, scanning images for vulnerabilities must be standard practice. Also, while building a container, it is wise to keep in mind where it will exist. For example, container networks act as user-defined namespaces and bridges that offer basic isolation through monitoring the traffic flow in virtual network adapters. Consider leveraging existing security systems in individual containers.
Most importantly, establishing and defining attack surfaces allows developers, organizations and engineers to thwart potential threats in the future. Understanding what services and containers occupy which namespace, which containers can communicate, which services are exposed and where threats exist are some of the things to examine.
3. Create a Container Operationalization Process
Containerization technology, organizational capacity and business needs are constantly evolving. Embracing containerization early significantly improves a business’ ability to evaluate, evolve and use containers as well as the value it offers users. Businesses must ensure operationalization aligns with users’ needs since failure to do so will result in low adoption and a waste of resources. Strategies include pilot projects, evaluation, rollout procedures, security update cycles and roadmaps for evolution.
4. Educate People and Give Them Time to Transition
Planning, educating and training can considerably decrease development time and risks arising from transition. For developers not used to containers, they may take time to embrace development in a container environment. At first, it could be slow, but containers can avoid most downstream development problems such as library mismatches. In the end, it speeds development. Also, different stakeholders in the development and deployment of containers may require different training.
5. Continuous Maintenance
Libraries, tools and platforms constantly fix security issues and defects. So, all container deployment strategies must accommodate updates. Initially, the use of automatic updates on container start can be appealing. However, it can result in an increase in startup times which reduces stability and reproducibility. Developers should frequently delete unused or unnecessary packages and assets during maintenance, test alterations and redeploy.
Do maintenance regularly. Hence the need for appropriate allocation of budget and resources. Since images can build up fast, it is good to have an image management strategy. When redeploying new images, restart all the existing containers using the new images. If container hierarchies exist, consider rebuilding all dependent containers accordingly.
