From Java code in your repo to a running Pod on Kubernetes. This article explains all the steps needed, including basic shortcuts.
Category: Containers
Are you a developer or just a curious individual who wants to dip their toes in the Cloud, but are not sure whether to go for OpenShift Local or Single Node OpenShift? You’ve come to the right place. In this article, I will explore the differences and similarities between these two variants of OpenShift, so […]
Kelsey Hightower stated already in 2017, that Kubernetes is not a Platform by itself, but rather a better way to start to build a platform. But what does that really mean? From my point of view, this means that Kubernetes is a platform that provides a core abstraction- and Service layer for cloud-native applications to […]
This walk-through example will encourage you to build an Apache Camel application from scratch, deploy it in a Kubernetes environment, gather metrics using Prometheus and display them in Grafana. Monitoring will automatically adjust when the system scales up or down. Table of Contents Introduction About Prometheus To-Do overview Scraping data The application Enabling Prometheus Enabling […]
OpenShift 3.3 and later contain the functionality to route pod traffic to the external world via a well-defined IP address. This is useful for example if your external services are protected using a firewall and you do not want to open the firewall to all cluster nodes. The way it works is that a egress […]
In the OpenShift world, Services take place on the OSI Layer 3 / IP, while Routing is an OSI Layer 7 / HTTP/TLS concept. Once you’ve wrapped your head around this backwards choice of naming, things are fairly easy: An OpenShift Router is a component which listens on a physical host’s HTTP/S ports for incoming […]
To allow stable endpoints in an environment of ever changing starting and stopping Pods (and therefore constantly changing IP addresses), Kubernetes introduces (and OpenShift uses) the concept of services. Services are stable IP addresses (taken per default from the 172.30.0.0/16 subnet) that remain the same as long as the service exists. Connection requests to a […]
So far, this sounds like a lot of effort to achieve a little more than a plain docker host – containers that can talk to each other and to the host network, potentially segregated based on kubernetes namespace. However OpenShift SDN also allows pods on different nodes to communicate with each other. To this end, […]
In OpenShift, networking is equally simple from a container point of view. Within the container’s namespace there is a eth0 network interface configured and services such as DNS just work. You can still use dedicated NICs on the host to isolate specific types of traffic. What’s the difference? It turns out there is hardly any […]
From a container point of view, networking on a plain Docker Host is simple. A running container is nothing more than a Linux process which is namespaced and constrained with regards to access (SELinux) and resource consumption (cgroups). In each namespace, there is a single (virtual) network interface called eth0 which is assigned an IP […]