DEVOPSdigest

In the cloud world, containers are the center point of a growing majority of deployments. By providing compartmentalization of workloads and the ability to run "serverless," containers can speed up and secure deployments and create flexibility unreachable by old style application servers. While a variety of tools have been developed to meet this need, none are as impactful to the industry as Kubernetes. It has emerged as the de facto container orchestration tool for many companies.

Kubernetes alone is a powerful framework, but relies entirely on proper configurations to achieve the desired results. Kubernetes facilitates the ability to automate the DevOps CI/CD pipeline but alone can be unwieldy.

In this blog, you will learn how to build, migrate to and integrate security in a fully-managed Infrastructure-as-Code CI/CD (Continuous Integration and Continuous deployment) pipeline for container-based applications — with low-code automation.

From Dependency Hell to Containers

By eliminating the "dependency hell" problem containers solved one of the most fundamental issues plaguing the software industry. They allow developers to keep their applications abstract from underlying environments, increasing agility and robustness.

Containers achieve several key performance metrics critical in modern software development, including consistent and predictable environments, ability to function virtually from anywhere, providing logically isolated view of the OS to developers and easy replication. Because of their lightweight nature, containers can be shipped as deployable units from different environments, complete with their libraries and configuration.

The Problem with Containers

But containers need to be managed properly. You could have thousands of containers in an environment, with open ports, different addresses and a host of applications.

What if a container fails while in production?

How would the system switch to other containers?

With containers the industry felt the need for a container orchestration tool, which could allocate resources, provide abstracted functionality like internal networking and file storage, and monitor health of these systems.

This is the key problem solved by Kubernetes.

Kubernetes to the Rescue

Kubernetes is a platform for containerized workloads and services offering both declarative configuration and automation. Kubernetes makes it possible to fully exploit the true powers of containers and achieve the primary goals of Continuous Integration, Delivery, and Deployment (CI/CD).

Let's see how Kubernetes makes all of this possible and where does it fit in the broader DevOps and CI/CD ecosystem.

Deployment

Kubernetes uses clusters for automatic deployment of containerized microservice applications. You can use triggers in Kubernetes Deployment engine to automate anything.

The Power of Configurations

You can define your own deployments and Kubernetes enforces your requirements based on defined states. You can define various aspects of your infrastructure deployment in Kubernetes including deployment objects (pods). You can easily create, update and delete Kubernetes objects by storing multiple object configuration files in a directory and recursively creating and updating these objects as needed. Kubernetes also allows you to store and manage passwords, OAuth tokens, and SSH keys and deploy application configuration without rebuilding your container images.

Immutability

Because of its declarative nature and image immutability, Kubernetes offers a diverse range of mechanisms to maintain the system's state based on your desired outcomes. You can define Deployments to create new Replica Sets, and remove existing deployments to adapt to the new resources and deployments. Kubernetes can also automatically trigger roll backs in case of errors.

Scalability

Kubernetes uses configurations to achieve scaling and on-demand adaption. It can create and destroy containers as and when needed. Its ReplicationController can kill, create and supervise pods based on your requirements. On-demand infrastructure handling is implemented via container scheduling and auto-scaling, automatic health checks, replication, service naming, discovery and load balancing.

Zero Downtime and Optimized Performance

Kubernetes achieves zero downtime even in frequent deployment situations by incrementally updating Pods instances with new ones. Kubernetes creates and destroys containers based on system requirements. It also rolls backs to previous working state in cases of failure. Kubernetes' Pod Eviction lifecycle for gracefully shutting down clusters and creating new ones is also extremely useful in complex systems.

Kubernetes: Difficulties in Migration and Adoption

You are ready to use the magical powers of containerized software development and want to use Kubernetes for your company. But how to get started?

How and where to deploy Kubernetes?

Would containerized development be suitable for your company?

Several government and private entities do not support containerized software applications amid security policies. Deciding between directly deploying Kubernetes for your cloud environment or choosing a Platform as a Service (PaaS) approach is also extremely important for your future needs and business feasibility.

Faulty Migration Can Break Your System and Future Scalability

Migrating from VMs to containers could be disastrous if you don't take into account platform dependencies, system-level issues and server-side dynamics. For example, if you package more than one service inside a container during refactoring, you could end up losing your ability to scale, automate and expand your features.

Data Implementation and Storage

Remapping your data storage techniques to container-based data systems will also be critical. Refactoring or rewriting your application for containerization involves completely rewiring your architecture.

Security Challenges

Implementing Kubernetes comes with a variety of security challenges that can compromise your entire application if not handled carefully. According to the State of Kubernetes and Container Security report, a whopping 94% companies said they ran into problems while implementing Kubernetes, including misconfiguration, runtime threats or vulnerabilities.

Some security issues while migrating to containerized environments include using insecure base or parent images, running misconfigured services, outdated processes and using faulty namespaces.

Overall, if you rely on Kubernetes alone for container orchestration, things could become extremely complex and difficult because of hard configurations, technical requirements and manual processes.