Running Docker Containers on Kubernetes Without a Container Runtime Using WasmEdge

KEY TAKEAWAYS

1. WasmEdge functions as a stand-alone option. It replaces traditional OCI runtime systems with its own faster and lighter solution.
2. These containers provide faster startups and reduced resource consumption. So, the performance is faster alongside minimal overhead expenses.
3. The secure sandboxing of WasmEdge containers creates an improved security environment that cuts down system vulnerabilities while reducing the exposed attack area.
4. WasmEdge containers can run on various hardware architectures. Some of the common include x86 together with ARM and RISC-V while maintaining full portability without needing any modifications.
5. WasmEdge allows users to perform simplified Kubernetes deployments that work perfectly with edge computing alongside serverless applications.

INTRODUCTION

The application running landscape has undergone a complete revolution through docker containers. These create isolated systems that can be easily managed. Kubernetes workloads traditionally depend on OCI runtimes, including containers and CRI-O, for executing container operations. A newer and more efficient solution known as WebAssembly (Wasm) containers with WasmEdge technology emerges as an alternative.

In this guide, I will explain the practical implementation of running WebAssembly-based containers on Kubernetes through WasmEdge by avoiding traditional container runtimes. Moreover, it covers complete explanations, starting from configuration deployment to debugging tasks and performance evaluations. You will end up with complete knowledge about deploying WasmEdge to implement containers that deliver high efficiency and speed alongside architectural portability.

WHY REPLACE OCI RUNTIMES WITH WEBASSEMBLY

Before jumping into the setup and practical steps, let’s first understand why you might want to replace OCI runtimes with WasmEdge.

PERFORMANCE GAINS WITH WASMEDGE

WasmEdge provides superior performance. It should be the primary reason to choose the platform. The initialization and resource usage of traditional containers last a long time. WasmEdge exists for fast operation. These containers begin operations in milliseconds while requiring fewer system resources. So they become suitable for time-sensitive applications and devices that operate under resource limitations, such as edge systems, and IoT components.

When developing an application that needs speed-based scaling according to user demand, you should consider it. WasmEdge containers can establish themselves practically instantaneously compared to how long traditional Docker containers take to begin their operation. They offer a breakthrough benefit for systems that must respond in critical periods like serverless computing and edge computing deployments.

SECURITY

Standard containers provide running security issues when deployed in operational systems. The main vulnerability of running your container environment exposes applications to potential attacks that could harm neighboring applications sharing the same infrastructure.

Each WebAssembly workload receives an isolated sandbox environment through WasmEdge execution. A new security layer is created through WasmEdge implementation effectively. It minimizes the vulnerable points in your system. Each WasmEdge container provides a secure environment that makes it harder for malicious code to spread. Therefore, the host system remains secure.

In addition, the security model proves critical for multi-tenant cloud deployments and microservice development. Since it provides necessary isolation between various applications. The implementation of WasmEdge benefits developers who aim to establish application resistance against attacks.

CROSS-PLATFORM COMPATIBILITY

Among the useful features of WasmEdge is its capability to work across multiple platforms. The normal deployment of containers between different platforms like x86 and ARM requires modifications either in container images/platform-specific configuration implementation. WasmEdge shows different behavior in this respect. The container engine operates without issues on multiple processor systems that include x86 ARM and RISC-V.

WasmEdge operates containers on cloud servers, edge devices, and Raspberry Pi without any changes to the initial configuration. The high level of portability reduces deployment complexity. Because your application needs to function within diverse execution environments.

IDEAL FOR EDGE AND SERVERLESS COMPUTING

WasmEdge demonstrates exceptional performance within edge and serverless computing domains. It's compatible with handling small and quick booting containers. WasmEdge serves efficient workloads because engineers developed it specifically for lightweight, small systems that need fewer resources than traditional containers. WasmEdge works flawlessly in situations where equipment has restricted processing power, such as smart sensors, edge devices, and IoT setups.

WasmEdge serves developers who construct microservices or serverless applications through its optimal features. The quick boot times of containers match their need for scarce resources while operating. Such performance attributes make WasmEdge ideal for applications that require fast responsiveness under various traffic conditions, such as event-driven workloads or stateless applications.

SETTING UP KUBERNETES FOR WASMEDGE CONTAINERS

This section will explain the necessary steps for WasmEdge installation on Kubernetes platforms, although the Kubernetes experience is beneficial.

PREREQUISITES

The following items should be checked before starting:

• A Kubernetes 1.26+ cluster. WasmEdge deployment requires a Kubernetes service provider.

• Your cluster needs Kubectl installation with optimal configuration to access it from any location.

• All Kubernetes nodes must have WasmEdge runtime running.

• Container with Wasm support, and CRI-O with WasmEdge integration.

  
  

Install the WasmEdge on Kubernetes nodes by using the command below:

curl -sSf https://raw.githubusercontent.com/WasmEdge/WasmEdge/master/utils/install.sh | bash

After installation, make sure that WasmEdge is installed rightly:

wasmedge --version

This should return the version of WasmEdge you’ve installed.

CONFIGURING KUBERNETES FOR WASMEDGE

Your Kubernetes environment requires registration of WasmEdge as its runtime for containers. The process needs you to establish WasmEdge Runtime Class configuration for Kubernetes usage. WasmEdge can be used by Kubernetes instead of the default container, and CRI-O runtimes through this configuration.

Create a RuntimeClass YAML file for WasmEdge:

apiVersion: node.k8s.io/v1
kind: RuntimeClass
metadata:
  name: wasmedge
runtimeHandler: wasmedge

Apply this configuration using:

kubectl apply -f runtimeclass-wasmedge.yaml

This tells Kubernetes to use WasmEdge as a valid runtime for your containers.

DEPLOYING A WEBASSEMBLY (WASM) CONTAINER FOR KUBERNETES

Now, let’s discuss, how can you deploy a WebAssembly (Wasm) Container on Kubernetes:

CREATING A WASMEDGE-BASED DOCKER IMAGE

First, convert your application into a WebAssembly (Wasm) module. For example, try a Rust-based HTTP server and convert it into a Wasm module. Next, install the wasm-pack tool.

It helps you compile Rust code into WebAssembly:

cargo install wasm-pack

Build the Rust app into a Wasm module:

wasm-pack build --release --target=wasm32-wasi

The Wasm module requires setup before it can be deployed to Docker Hub and ORAS container registries. Kubernetes can obtain Wasm images through this mechanism during its deployment process.

Example:

docker push myrepo/wasm-app:latest

DEPLOYING THE WASMEDGE CONTAINER

Now, you’re ready to deploy the Wasm-based container on Kubernetes. Create a deployment YAML file for Kubernetes to use:

apiVersion: apps/v1
kind: Deployment
metadata:
  name: wasm-app
spec:
  replicas: 2
  selector:
    matchLabels:
      app: wasm-app
  template:
    metadata:
      labels:
        app: wasm-app
    spec:
      runtimeClassName: wasmedge
      containers:
        - name: wasm-container
          image: myrepo/wasm-app:latest
          command: ["/wasm-app.wasm"]

Now, apply this deployment file to Kubernetes:

kubectl apply -f wasm-deployment.yaml

The WasmEdge container receives deployment through Kubernetes with two exact duplicates enabled. The deployment status can be checked by running this command:

kubectl get pods -l app=wasm-app

The above command provides a quick overview of the deployment status.

RUNNING AND DEBUGGING WASM CONTAINERS

Once deployed, it's imperative to verify that everything is working as intended. Let’s talk about some practical commands to monitor and troubleshoot your WasmEdge containers.

VERIFYING THE DEPLOYMENT

To check if your WasmEdge container is running, use:

kubectl get pods -l app=wasm-app

If everything is running in the right manner, this should show the pods associated with your deployment.

To check the logs for a specific pod:

kubectl logs <pod-name>

TROUBLESHOOTING

If you face any issues with your container, use the Kubectl describe pod to see detailed information:

kubectl describe pod <pod-name>

The command will show you the events related to the pod. It can help you debug issues such as image pull errors or misconfigurations. Additionally, WasmEdge provides a CLI tool to validate your Wasm module. To certify that your Wasm module is accurately built and ready to run, use

wasmedge --validate my-wasm-app.wasm

This will check for any potential issues with the Wasm module before you deploy it.

BENCHMARKING WASMEDGE VS. OCI CONTAINERS

It’s important to compare the performance of WasmEdge containers with traditional OCI containers. Let’s look at a few performance benchmarks to see how WasmEdge performs.

STARTUP TIME COMPARISON

One of the most significant benefits of WasmEdge is the startup time. To evaluate the startup latency, run both WasmEdge and OCI containers using the time command:

time docker run myrepo/wasm-app
time wasmedge run myrepo/wasm-app.wasm

MEMORY & CPU USAGE

To compare memory and CPU usage, use the kubectl top pods command:

kubectl top pods

This will show you how much CPU and memory your containers are consuming. WasmEdge containers should consume far fewer resources than their OCI counterparts. For even more detailed profiling, use wasm-stats:

wasm-stats my-wasm-app.wasm

It will help you understand how efficiently WasmEdge handles your workload.

CONCLUSION

WasmEdge offers users lightweight and secure container runtime functions. It replaces existing traditional OCI runtimes effectively. OCI runtime containers will become more effective when you migrate to WasmEdge because your applications will start faster and use fewer resources, while the sandbox security measures improve system safety.

WasmEdge operates across multiple platforms. So, it means your containers can function on x86 devices as well as ARM and RISC-V devices without changing any configurations.

The guide presents simple deployment and management instructions for WasmEdge containers on Kubernetes systems. WasmEdge proves to be an ideal solution for developers who create microservices and serverless applications as well as edge deployments.