Knative Unveiled: A Comprehensive Guide to Serverless Kubernetes


Serverless computing has emerged as a game-changing technology that is transforming the way businesses develop and deploy applications. At the forefront of this revolution is Knative, an open-source platform designed to simplify the deployment and management of serverless workloads on Kubernetes.

Definition of Knative and its significance in the world of serverless computing

Knative is a Kubernetes-based platform that enables developers to easily deploy, run, and manage serverless workloads. It provides a set of middleware components that integrate with Kubernetes to provide a higher-level abstraction for building, deploying, and managing serverless applications.

Knative consists of several key components, including:

  • Serving: A component that allows developers to deploy serverless functions or applications using Knative’s API. Serving can automatically scale up or down based on demand.
  • Eventing: A component for building event-driven architectures using Knative’s API. This allows developers to build real-time processing pipelines by connecting services together via events.
  • Build: A container build system that can automatically build container images from source code and Dockerfiles. Build also allows developers to easily update or roll back deployments with zero downtime.

Knative’s significance lies in its ability to make it easier for developers to build and deploy serverless applications on Kubernetes, one of the most popular container orchestration platforms currently available.

Overview of what the guide will cover

This comprehensive guide will provide an overview of Knative and its key components, as well as step-by-step instructions for getting started with building and deploying serverless applications using Knative. The guide will cover everything from setting up a development environment for Knative, to building scalable, resilient serverless applications using best practices and advanced techniques. We will also explore how to monitor and manage Knative-based deployments and integrate third-party services via service brokers.

By the end of this guide, readers should have a comprehensive understanding of what Knative is, how it works, and how it can be used to build powerful serverless applications on Kubernetes. Whether you’re an experienced developer or new to the world of serverless computing, this guide offers valuable insights and practical tips for achieving success with Knative.

Understanding Serverless Computing

What is Serverless Computing?

Serverless computing is a cloud computing model that enables developers to focus solely on writing and deploying code without having to worry about managing the underlying infrastructure. With serverless computing, developers can build applications without worrying about servers, virtual machines, or hardware. In this model, the cloud provider takes care of managing the infrastructure and automatically scales it based on application demand.

The Benefits of Serverless Computing

One of the primary benefits of serverless computing is cost savings. Since serverless computing charges users only for what they use, it eliminates the need for companies to overprovision resources in anticipation of traffic spikes.

This means that companies no longer have to pay for idle resources during periods of low usage. Another benefit is scalability.

With serverless computing, applications can automatically scale up or down based on incoming traffic demands without any intervention from developers or operations teams. Serverless also allows for faster time-to-market since developers can focus solely on writing code instead of spending time configuring and managing servers.

Comparison Between Traditional Server-Based Architecture and Serverless Architecture

In traditional server-based architecture, an application runs on one or more dedicated servers that are provisioned with enough resources to handle peak usage scenarios. As a result, companies often end up paying for idle resources during periods of low usage. On the other hand, in serverless architecture, there are no dedicated servers.

Instead, each function runs in its own container with just enough compute capacity to handle incoming requests. As soon as the request is processed, the container shuts down and frees up resources for other requests.

This approach eliminates the need to provision dedicated servers and allows companies to save money while ensuring that their application can handle peaks in traffic demand without any downtime. Additionally, serverless architectures offer better fault tolerance since each function operates independently, and failures in one function do not impact other functions.

Introduction to Kubernetes

Kubernetes is an open-source platform that automates container deployment, scaling, and management. It was originally developed by Google in 2014 and is now maintained by the Cloud Native Computing Foundation (CNCF). With Kubernetes, you can manage containerized applications in a highly efficient and scalable manner.

Brief overview of Kubernetes and its role in container orchestration

Kubernetes is designed to simplify the process of deploying and managing containers. Containers are lightweight virtual machines that package an application with all its dependencies into a single portable unit. With Kubernetes, developers can easily deploy containers across multiple hosts or clusters, scale applications up or down based on demand, and ensure high availability through automated failover mechanisms.

Kubernetes also provides a number of other key features for container orchestration such as service discovery, load balancing, scheduling, resource allocation, and automated rollouts/rollbacks. These features enable developers to build complex distributed systems that are resilient to failure and can adapt to changing workloads.

Explanation of how Kubernetes enables serverless computing

Serverless computing is a cloud computing model where the cloud provider manages the infrastructure required to run an application. This allows developers to focus on writing code without worrying about underlying infrastructure details such as servers or operating systems.

With serverless computing, applications are charged based on actual usage rather than on pre-allocated resources. Kubernetes enables serverless computing through its support for running serverless workloads in containers with Knative.

Knative provides a higher-level abstraction layer that simplifies the process of deploying serverless workloads within Kubernetes clusters. It provides features such as automatic scaling of resources based on usage patterns and event-driven workflows triggered by external events like messages from message queues or changes in data stored in databases.

Kubernetes plays a critical role in enabling serverless computing by providing powerful tools for container orchestration and management. Its support for running serverless workloads in containers makes it possible to build highly scalable, resilient applications that can adapt to changing workloads and user demands.

Introducing Knative

What is Knative?

Knative is an open-source platform for building, deploying, and managing modern serverless workloads on Kubernetes. It provides a set of middleware components that enable developers to build serverless applications by abstracting away the underlying infrastructure complexities. With Knative, developers can focus solely on writing business logic and leave the operational tasks such as scaling, routing, and monitoring to the platform.

Knative is designed to be highly extensible and modular. It is built on top of Kubernetes primitives such as Deployments, Services, and ConfigMaps, which make it easy to integrate with existing Kubernetes ecosystems.

Additionally, it exposes a rich set of APIs that allow developers to customize the behavior of their serverless workloads. Knative provides a portable abstraction layer that allows users to deploy their applications across multiple cloud providers or on-premises environments.

The history behind the creation of Knative

Knative was created in 2018 by Google in collaboration with other industry leaders including Pivotal, IBM, Red Hat, and SAP. The project was born out of a need for a standardized way of building serverless applications on Kubernetes. Before Knative’s existence, there were several proprietary solutions for building serverless applications on Kubernetes which made it difficult for developers to switch between different cloud providers or build hybrid cloud solutions.

The initial version of Knative was released in July 2018 as an alpha release with limited functionality. Since then, it has gone through several iterations and has become one of the most popular open-source projects in the Cloud Native Computing Foundation (CNCF) ecosystem.

Key features and benefits

Knative provides several key features that make it a powerful platform for building modern serverless applications: – Auto-scaling: Knative automatically scales up or down your serverless workloads based on incoming requests or changes in traffic patterns. – Build and deployment: Knative provides a build process that automatically builds and deploys your serverless applications to Kubernetes with zero downtime.

– Eventing: Knative provides a flexible event-driven architecture that allows you to build complex workflows by connecting various services together. – Serving: Knative provides a powerful routing layer that allows you to route traffic to different versions of your application based on criteria such as geographic location, user agent, or other parameters.

Overall, Knative provides a standardized way of building and managing serverless workloads on Kubernetes. It abstracts away the complexities of infrastructure management and allows developers to focus solely on writing business logic.

Getting Started with Knative

Setting up a Development Environment for Knative

Before you can start building serverless applications with Knative, you first need to set up a development environment. The process of setting up a development environment for Knative is similar to setting up a Kubernetes development environment. You will need to have Kubernetes installed on your machine or in the cloud, and then install Knative on top of it.

To get started, ensure that you meet the prerequisites for installing Kubernetes and then install it using your preferred method. Once Kubernetes is installed, download the latest release of Knative from Github and follow the installation instructions provided in the documentation.

You can also install Knative using pre-built binaries and images if you prefer not to build from source. Make sure to check the compatibility between your version of Kubernetes and version of Knative before installation.

Deploying Your First Application on Knative

Once your development environment is set up, it’s time to deploy your first application on Knative. To do this, you will need to create a Docker image containing your code and then push it to a container registry such as Docker Hub or Google Container Registry.

After pushing your image, create a YAML file defining your deployment configuration including details such as image name and resource requirements. Then use kubectl command-line tool or web interface like Kubernetes Dashboard application to deploy this configuration onto your cluster.

Knative will automatically take care of scaling based on demand which means applications are scalable without much additional setup required. Getting started with Knative is easy if you have experience with Kubernetes installation & configuration along with some basic Docker knowledge.Here we just touched upon how one can start developing serverless apps on top of kubernetes using knative by deploying simple hello world application but there are many other features available in knatve which makes working serverless apps more robust and efficient.

Building Serverless Applications with Knative

How to create a serverless application using Knative

Now that we have an understanding of what Knative is and how it works, let’s dive into building serverless applications using this platform. Creating a serverless application with Knative is similar to creating a containerized application with Kubernetes, but with some added benefits. One of the main features of Knative is its ability to automatically scale your application based on demand.

This means you only pay for the resources you use, saving you money in the long run. To create a serverless application on Knative, first, you need to package your code into a container image and upload it to a container registry like Docker Hub or Google Container Registry.

Once that’s done, you can deploy your application on Knative by creating a YAML file that describes how your app should run in the cluster. This file specifies things like which container image to use, how much CPU and memory each instance should have, and whether or not autoscaling should be enabled.

Best practices for building scalable, resilient applications with Knative

When building serverless applications with Knative or any other platform for that matter there are best practices to be followed so as to ensure scalability and resilience. One best practice is breaking up your application into smaller services rather than monolithic ones,. When you have smaller services performing specific functionalities then scaling becomes easier since each service can be scaled independently according to its own unique needs.

Another important practice is ensuring clean separation between components. Each component in your architecture should do one thing and do it well so as not hamper other services if something goes wrong.

security protocols at every stage of development must be implemented since security breaches could lead to destruction of data. By following these best practices as you build your apps with knative then ensure smooth scaling and resilience of the app.

Managing Serverless Applications with Knative

Monitoring and Logging with Knative

Once you have deployed your serverless application on Knative, it is essential to monitor and log the application’s activities. Knative offers an efficient way to collect and analyze metrics, logs, and traces of your applications. You can use tools like Prometheus for monitoring your serverless environment.

Prometheus is an open-source monitoring system that collects metrics from monitored targets at regular intervals. It stores these metrics in a time-series database, queryable via an HTTP API. It can help you monitor various performance metrics such as CPU usage, memory usage, network I/O usage, request latency, etc. You can also set up alerts for specific events or thresholds using Alert manager.

Knative also provides a centralized logging framework by default called Fluentd. It collects logs from all containers running in the cluster and sends them to a centralized location like Elasticsearch or Logstash for analysis. This helps developers troubleshoot issues quickly by providing them with easy access to a centralized repository of logs.

Scaling Applications Up or Down Based on Demand Using Autoscaling Features

One of the core benefits of serverless computing is its ability to scale applications automatically based on demand. With Knative’s autoscaling features, you can scale your serverless applications up or down based on traffic demands seamlessly. Knative uses two types of autoscaling: horizontal pod autoscaling (HPA) and event-driven autoscaling (EDA).

HPA automatically scales the number of replicas in a deployment based on CPU utilization or custom metrics defined by users. EDA scales workloads based on incoming events such as HTTP requests processed per second. To configure HPA in Knative, you need to define two things: the scaling target (the container(s) that need scaling) and the metric used for scaling (CPU utilization or custom metrics). Once HPA is enabled, it starts monitoring the metric and adjusts the number of replicas accordingly.

EDA works by creating a subscription to an event source and a trigger that executes when the subscription receives an event. The trigger then scales up or down the workload based on the number of events received. This enables developers to scale applications based on real-time events, like incoming HTTP requests.

Knative’s autoscaling capabilities enable developers to efficiently manage serverless applications without worrying about capacity planning and resource management. By using HPA and EDA in tandem with effective monitoring and logging practices, you can ensure that your serverless applications run smoothly and scale seamlessly to meet demand.

Advanced Topics in Serverless Computing with Knative

Using Event-Driven Architectures with Knative

One of the significant benefits of using Knative is its built-in support for event-driven architectures, which are ideal for building highly responsive and scalable applications. With this approach, applications can be triggered automatically based on certain events or predicates, such as data changes, user actions, or system alerts.

Knative provides a powerful framework for building event-driven applications that can respond quickly to changes in the underlying infrastructure or user behavior. It uses Kubernetes’ native programming model to create custom resources that define event sources and handlers.

These resources can be used to automate various tasks such as scaling up or down services based on demand, invoking serverless functions upon certain events, or routing requests dynamically based on specific criteria. In addition to providing an easy-to-use framework for building event-driven architectures, Knative also offers several tools for monitoring and debugging these types of systems.

For instance, it provides an intuitive dashboard that allows you to track metrics such as request latency, throughput, and error rates in real-time. This makes it easier to diagnose issues quickly and optimize your application’s performance over time.

Integrating Third-Party Services into Your Applications Using Service Brokers

Another significant advantage of using Knative is its ability to integrate seamlessly with various third-party services through the use of service brokers. Service brokers are essentially API gateways that allow developers to consume cloud-based services from different vendors without having to write any custom code or deal with complex configuration settings manually. Knative supports multiple service brokers out-of-the-box, including Google Cloud Platform (GCP), Amazon Web Services (AWS), and Microsoft Azure.

By leveraging these service brokers, you can easily incorporate various cloud services such as databases, messaging systems, machine learning models into your serverless application without worrying about the underlying infrastructure. For example, if you need to use a NoSQL database to store and retrieve data in your application, you can simply provision a GCP Cloud Datastore instance using the GCP broker and then bind it to your application.

This will create all the necessary resources automatically, such as tables, indexes, and access keys. You can then use standard APIs to interact with the database without worrying about the underlying implementation details.

Overall, Knative offers many advanced features that enable developers to build sophisticated serverless applications that can scale seamlessly and integrate with various services easily. By leveraging these capabilities, you can focus on building high-quality applications that meet your business needs without being constrained by the underlying infrastructure or technology stack.


Serverless computing has revolutionized the way developers build and deploy applications, allowing them to focus on writing code instead of managing infrastructure. The emergence of Kubernetes has brought serverless computing to a new level of scalability and flexibility. Knative, an open-source project built on top of Kubernetes, provides an important set of tools for developers looking to build and deploy serverless applications in a Kubernetes environment.

In this guide, we have explored the fundamentals of serverless computing and how it relates to Kubernetes. We have introduced Knative and its features, as well as explored how to create, manage, and scale serverless applications using Knative.

We have covered several advanced topics that demonstrate the power and flexibility of Knative. By leveraging the capabilities provided by Knative, developers can build resilient and scalable applications that take full advantage of Kubernetes’ flexible architecture.

As more organizations adopt Kubernetes as their preferred platform for container orchestration, it is clear that Knative will play an increasingly important role in enabling these organizations to embrace serverless computing. Knative represents a major step forward in our journey towards cloud-native architectures.

By providing a complete set of tools for building and deploying serverless applications in a Kubernetes environment, Knative enables developers to focus on writing code that solves business problems instead of worrying about infrastructure management. With its growing community support and rapid pace of innovation, the future looks bright for both Knative and the wider ecosystem around it.

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