We had the chance to see quite a bit of clusters in our years of experience with kubernetes (both managed and unmanaged - on GCP, AWS and Azure), and we see some mistakes being repeated. No shame in that, we’ve done most of these too!

I’ll try to show the ones we see very often and talk a bit about how to fix them.

We often find ourselved required to route traffic from external sources towards internal services deployed to a Kubernetes cluster. There are several ways of doing this, but the most common is to use the Service resource, or, for HTTP(S) workloads, the Kubernetes Ingress API. The latter is finally going to be marked GA in K8s 1.19, so let’s take this opportunity to review what it can offer us, what alternatives there are, and what the future of ingress in general could be in upcoming Kubernetes versions.
How to expose applications in Kubernetes

Usually, we use the Service resource to expose an application internally or externally: define an entry point for the application which automatically routes distributed traffic to available pods. Since pods tend to come and go – the set of pods running in one moment in time might be different from the set of pods running that application at some later point – the Service resource groups them together with a label selector.

Service resources are broken down by type for more versatile usage. The three most commonly used types are ClusterIP, NodePort and LoadBalancer. Each provides a different way of exposing the service and is useful in different situations.

A brief look at models for integrating Kubernetes clusters into existing networks.

binenv will help you download, install and manage the binaries programs (a.k.a. distributions) you need in you everyday DevOps life (e.g. kubectl, helm, ...).

Think of it as a tfenv + tgenv + helmenv + ...

Now you can install your favorite utility just by typing binenv install something.

Monoliths are the future because the problem people are trying to solve with microservices doesn’t really line up with reality.
Google cloud native adherent and evangelist Kelsey Hightower

Install Kubeadm to Configure Multi Nodes Kubernetes Cluster.

For IPTables, Kubernetes v1.15 has not supported IPTables version 1.8 yet now (Aug 2019 now), so switch to IPTables Legacy on Debian 10.

Here’s something you can do before work, with your morning coffee, or whilst waiting for dinner to cook of an evening. And there’s never been a better time to install Kubernetes to a Raspberry Pi, with the price-drop on the 2GB model — perfect for containers.