Kubernetes for the absolute beginner III
What are kubernetes Ingress and Egress?
What is an Ingress Controller?
What are Replica and ReplicaSet?
What is Service Mesh?
Consider that you want to test Nginx’s new release to check if it’s compatible with your web application. You have created a new container (Container2) with the new Nginx version and copied over your current Nginx webserver config from the current container (Container1). But you don’t want to affect the other microservices that make up the web application (assuming each container corresponds to a separate microservice) – that is, the MySQL database, the Node.js frontend, the load balancers, etc. So using a service mesh setup, you can instantly change only the webserver microservice to Container2 (the one with the new Nginx version) for testing. And if you determine it does not work, say because it causes some compatibility issues with your website, then you call on the service mesh to quickly switch back to the original Container1. And all this without making any other configuration changes to any of the other containers – the changes are completely transparent to the other containers. Without a service mesh setup, this would be a tedious task involving changing configuration settings on all other containers, one by one, to point the services they contain from Container1 to Container2, and then after the testing failure, changing them all back. Read more about service mesh in this article.
In the next article, we shall take a look at some more topics surrounding Kubernetes – how do you get started on learning Kubernetes, how to install and test Kubernetes locally, and some great monitoring and security tools for Kubernetes.