Tag Archives: Cilium

Red Hat OpenShift - Cilium CNI Migration - Header

How to migrate from Red Hat OpenShiftSDN/OVN-Kubernetes to Cilium

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Recently, I’m seeing more and more queries about migrating to Cilium within an existing Red Hat OpenShift cluster, due to Cilium’s advanced networking capabilities, robust security features, and enhanced observability out-of-the-box. This increase of interest is also boosted by the fact that Cilium became the first Kubernetes CNI to graduate in the CNCF Landscape.

In this blog post, we’ll cover the step-by-step process of migrating from the traditional OpenShiftSDN (default CNI pre-4.12) or OVN-Kubernetes (default CNI from 4.12) to Cilium, exploring the advantages and considerations along the way.

If you need to understand more about the default CNI options in Red Hat OpenShift first, then I highly recommend this blog post, as pre-reading before going through this walkthrough.

Cilium Overview

For those of you who have not heard of Cilium, or maybe just the name and know there’s a buzz about it. In short Cilium, is a cloud native networking solution to provide security, networking and observability at a software level.

The reason why the buzz is so huge is due to being implemented using eBPF, a new way of interacting and programming with the kernel layer of the OS. This implementation opens a whole new world of options.

I’ll leave you with these two short videos from Thomas Graf, co-founder of Isovalent, the creators of Cilium.

Does Red Hat support this migration?

Cilium has achieved the Red Hat OpenShift Container Network Interface (CNI) certification by completing the operator certification and passing end-to-end testing. Red Hat will support Cilium installed and running in a Red Hat OpenShift cluster, and collaborate as needed with the ecosystem partner to troubleshoot any issues, as per their third-party software support statements. This would be a great reason to look at Isovalent Enterprise for Cilium, rather than using Cilium OSS, to get support from both vendors.

However, when it comes to performing a CNI migration for an active existing OpenShift cluster, Red Hat provides no guidance, unless it’s migrating from OpenShiftSDN to OVN-Kubernetes.

This means CNI migration to a third party CNI in an existing running Red Hat OpenShift Cluster is a grey area.

I’d recommend speaking to your Red Hat account team before performing any migration like this in your production environments. I have known large customers to take on this work/burden/supportability themselves and be successful.

Follow along with this video!

If you prefer watching a video or seeing things live and following along, like I do at times, then I’ve got you covered with the below video that covers the content from this blog post.

Pre-requisites and OpenShift Cluster configuration
As per the above, understand this process in detail, and if you follow it, you do so at your own risk.

For this walkthrough, I’ve deployed a OpenShift 4.13 cluster with OVN-Kubernetes, with a sample application (see below). You can see these posts I’ve written for deployments of OpenShift, or follow the official documentation.

Here is a copy of my install-config.yaml file. It was generated using the openShift-install create install-config wizard. Then I ran the openshift-install create cluster command. Continue reading How to migrate from Red Hat OpenShiftSDN/OVN-Kubernetes to Cilium →

Tanzu Kubernetes Grid Cilium Header

How to Deploy a Tanzu Kubernetes Grid cluster using the Cilium CNI

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In this blog post I’m going to dive into how you can create a Tanzu Kubernetes Grid cluster and specify your own container network interface, for example, Cilium. Expanding on the installation, I’ll also cover installing a load balancer service, deploying a demo app, and showing some of the observability feature as well.

What is Cilium?
Cilium is an open source software for providing, securing and observing network connectivity between container workloads - cloud native, and fueled by the revolutionary Kernel technology eBPF

Let’s unpack that from the official website marketing tag line.

Cilium is a container network interface for Kubernetes and other container platforms (apparently there are others still out there!), which provides the cluster networking functionality. It goes one step further than other CNIs commonly used, by using a Linux Kernel software technology called eBPF, and allows for the insertion of security, visibility, and networking control logic into the Linux kernel of your container nodes.

Below is a high-level overview of the features.

TKG Cilium - Features

And a high-level architecture overview.

Cilium Architecture

Is it supported to run Cilium in Tanzu Kubernetes cluster?

Tanzu Kubernetes Grid allows you to bring your own Kubernetes CNI to the cluster as part of the Cluster bring-up. You will be required to take extra steps to build a cluster during this type of deployment, as described below in this blog post.

As for support for a CNI outside of Calico and Antrea, you as the customer/consumer must provide that. If you are using Cilium for example, then you can gain enterprise level support for the CNI, from the likes of Isovalent.

Recording

How to deploy a Tanzu Kubernete Cluster with Cilium

Before we get started, we need to download the Cilium CLI tool, which is used to install Cilium into our cluster.

The below command downloads and installs the latest stable version to your /usr/local/bin location. You can find more options here. Continue reading How to Deploy a Tanzu Kubernetes Grid cluster using the Cilium CNI →