CKA Full Course 2024: Day 4/40 Why Kubernetes Is Used?

Lloyd Rivers - Oct 21 - - Dev Community

So, you've probably been working with Docker containers for a while now, right? I know the excitement of spinning up that first container feels like magic—but then reality hits. You start noticing how managing containers at scale can quickly become a logistical nightmare. That’s when Kubernetes (K8s) enters the room like a seasoned project manager, ready to take over and streamline everything.

In this post, we’ll look at the challenges of standalone containers, how Kubernetes helps solve those headaches, and when (and when not) to use Kubernetes. Let’s get into it!


The Challenges of Standalone Containers

If you’ve worked with standalone containers, these problems might sound familiar:

1. Manual Scaling

Scaling standalone containers is like playing a game of whack-a-mole. Need more capacity? Manually start up another container. Oh, need to reduce resources now? Manually shut down some containers. This quickly becomes unmanageable, especially when you have unpredictable traffic spikes.

2. Service Discovery

How do your containers talk to each other? With Docker, you end up needing to hard-code IP addresses or set up some custom networking that just doesn’t feel natural. It’s clunky and hard to maintain.

3. Health Checks and Recovery

What happens when one of your containers goes down? Standalone Docker doesn’t handle that well on its own. You’ll need to monitor everything and restart dead containers manually. And we all know how much fun that sounds at 3 AM on a Saturday.

4. Complex Deployments

Managing multi-container apps gets tricky. You need to coordinate how they interact, handle their dependencies, and make sure they’re all up at the right time. Suddenly, a simple app feels like a house of cards.


Kubernetes, the container orchestrator that everyone’s talking about, automates a lot of these pain points. Here’s how it steps in and saves the day:

1. Automated Scaling

K8s allows you to define scaling rules based on CPU or memory usage. You can set it to automatically spin up more containers when traffic increases and shut them down when things cool down. No more babysitting.

2. Service Discovery Made Easy

With Kubernetes, your containers don’t need to worry about where everything is. K8s automatically assigns DNS names to services, so your containers can communicate smoothly.

3. Self-Healing

If a container dies, Kubernetes automatically restarts it. No more scrambling out of bed to restart your containers at the crack of dawn. K8s keeps your app running smoothly with its self-healing powers.

4. Simplified Deployments

K8s handles complex multi-container apps with ease. It organizes them into pods and services, making it easy to roll out new versions, handle dependencies, and ensure everything’s working in harmony.


When Should You Use Kubernetes?

So, Kubernetes sounds awesome, but it’s not a silver bullet for every problem. Here are five cases where Kubernetes is the right choice:

1. When You Need to Scale Automatically

If your app sees fluctuating traffic or you need to automatically adjust resources on the fly, Kubernetes’ autoscaling is a game-changer.

2. Microservices Architecture

If your app is composed of microservices, K8s makes it easier to manage multiple services and ensure they’re all communicating smoothly.

3. Self-Healing Requirements

Need an app that stays resilient even when parts of it fail? Kubernetes’ self-healing capabilities ensure downtime is minimal.

4. CI/CD Pipelines

If you’re building a Continuous Integration/Continuous Deployment pipeline, Kubernetes’ rolling updates and easy rollback features make it a great choice.

5. Hybrid and Multi-Cloud Deployments

K8s is ideal if you need to manage workloads across multiple cloud providers or your own data centers. It abstracts away the infrastructure so you can focus on your app.


When Should You Not Use Kubernetes?

But Kubernetes isn’t always necessary. Here’s when you might want to avoid the complexity:

1. Small, Simple Apps

If your app is a small, one-container service, Kubernetes is overkill. Stick with Docker for simplicity.

2. Learning Curves

If your team is new to containers, jumping straight into Kubernetes can be daunting. Master Docker first before diving into K8s.

3. Low Traffic, Simple Deployments

For apps with predictable, low traffic that don’t need constant scaling or failover, Kubernetes’ overhead isn’t worth it.

4. Short-Lived Projects

If you’re spinning up something temporary, like a hackathon project or a quick POC, Kubernetes can be more trouble than it’s worth.

5. Resource-Constrained Environments

K8s can be resource-heavy. If you’re working in an environment with limited CPU, memory, or storage, it might slow you down more than it helps.


Key Takeaways

Kubernetes is a fantastic tool when you need scalability, resilience, and smooth container orchestration. It takes the burden off your shoulders by automating many complex tasks that are hard to manage manually with standalone containers. However, don’t jump into it just because it’s trendy. Evaluate your app’s needs first.

If you’re running small, predictable apps, Docker alone might be enough for you. But as you grow and scale, Kubernetes will become your best friend.


Challenges Faced and Learnings

As a junior developer, I’ll admit that the sheer scope of Kubernetes and all its moving parts—Pods, Services, Ingress, autoscaling—can be overwhelming. It’s easy to get lost in its capabilities. But the key lesson is knowing when to keep things simple and when the complexity is actually worth it. Always weigh the pros and cons carefully, because sometimes sticking with standalone containers can save a lot of time and headaches.


Tags and Mentions

@piyushsachdeva
Day 4 video

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