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10 posts tagged with "Open Source"

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K8s Troubleshooting Insights: Looking into CoreDNS Issues

· 8 min read
Eleni Grosdouli
DevOps Consulting Engineer at Cisco Systems

Introduction

Welcome to the the first post of the brand new Kubernetes Troubleshooting Insights section! The series of blog posts will share helpful information and troubleshooting tips for issues that might appear in a Kubernetes environment. The posts are focused on real-life scenarios from either test, staging or production environments.

In today’s blog post, we’ll explore an issue with CoreDNS setup on RKE2 clusters. Cilium CNI with Hubble were enabled for this setup. Let’s jump right in!

title image reading "It's not DNS"

Sveltos: Optimising Day-2 Operations with Cilium and Tetragon

· 8 min read
Eleni Grosdouli
DevOps Consulting Engineer at Cisco Systems

Introduction

How easy is it to handle Day-2 operations with existing CI/CD tooling? Sveltos provides the ability to perform not only Day-1 operations but also helps platform administrators, tenant administrators and other operators with Day-2 operations. For example, we can use the HealthCheck and the ClusterHealthCheck features to not only watch the health of a cluster but also collect information from the managed clusters and display them in the management cluster.

In today's blog post, we will cover a way of deploying Cilium as our CNI alongside Cilium Tetragon for observability. We will then continue with a simple TracingPolicy deployment to capture socket connections and then use Sveltos to display the tracing results back to the management cluster.

The goal of the demonstration is to showcase how Sveltos can be used for different Kubernetes cluster operations based on the use case at hand.

title image reading "Sveltos Health Check"

Sveltos Tiers: Efficient Day-2 Operations and Targeted Updates

· 8 min read
Eleni Grosdouli
DevOps Consulting Engineer at Cisco Systems

Introduction

In previous posts, we outlined how Sveltos allows Platform and tenant administrators to streamline Kubernetes applications and add-on deployments to a fleet of clusters. In today's blog post, we will take a step further and demonstrate how easy it is to target and update a subset of resources targeted by multiple configurations. By multiple configurations, we refer to the Sveltos ClusterProfile or Profile Custom Resource Definitions (CRDs). The demonstration focuses on day-2 operations as we provide a way to update and/or remove resources without affecting production operations.

This functionality is called tiers. Sveltos tiers provide a solution for managing the deployment priority when resources are targeted by multiple configurations. Tiers are easily integrated into existing ClusterProfile/Profile definitions alongside defining the deployment order control and straightforwardly override behaviour.

Today, we will cover the case of updating the Cilium CNI in a subnet of clusters with the label set to tier:zone2 without affecting the monitoring capabilities defined in the same ClusterProfile/Profile.

title image reading "Sveltos Tiers"

OSSummit Europe 2024

· 4 min read
Eleni Grosdouli
DevOps Consulting Engineer at Cisco Systems

Introduction

Sveltos is on tour! Another non-technical post describing my experience at the OSSummit Europe 2024. Apart from outlining my experience, the post will include useful resources on open-source projects I learned during the event.

About Sveltos, Gianluca Mardente and I had the chance to talk at the conference and present Sveltos and how it is used to deploy and manage different Kubernetes applications and add-ons in a Multi-Cloud setup.

In the sections below, I will outline my highlights of the conference and what I have learned, while later on, I will describe what we presented about Sveltos and where to locate the required resources.

title image reading "OSSummit Europe 2024"

Civo Navigate Berlin 2024

· 3 min read
Eleni Grosdouli
DevOps Consulting Engineer at Cisco Systems

Introduction

Today's post will not be as technical as previous ones however, I wanted to share my experience at the Civo Navigate in Berlin. I had the chance to talk at the conference, present Sveltos and how it can be used to painlessly deploy different Kubernetes applications and monitoring capabilities on a fleet of clusters.

Apart from that, I attended many different sessions covering relevant topics (Cloud native, Security, Thought Leadership, AI) and meet fellow enthusiasts.

In the sections below, I will outline some of my highlights and afterwards provide an introduction to the Sveltos presentation alongside the useful resources.

title image reading "Civo Navigate Berlin 2024"

OpenTofu: RKE2 Cluster with Cilium on Azure

· 11 min read
Eleni Grosdouli
DevOps Consulting Engineer at Cisco Systems

Introduction

In a previous post, we covered how to create an RKE2 cluster on Azure Cloud using the cloud-free credits from the Rancher UI. As this is a convenient approach to get started with Rancher, in today's post, we will demonstrate how to use OpenTofu to automate the deployment.

OpenTofu is a fork of Terraform. It is an open-source project, community-driven, and managed by the Linux Foundation. If you want to get familiar with what OpenTofu is and how to get started, check out the link here.

Additionally, we will demonstrate how easy it is to customise the Cilium configuration and enable kube-vip for LoadBalancer services from the HCL (HashiCorp Configuration Language) definition.

title image reading "OpenTofu Rancher RKE2 Cluster on Azure"

Sveltos Templating: Cilium Cluster Mesh in One Run

· 8 min read
Eleni Grosdouli
DevOps Consulting Engineer at Cisco Systems

Introduction

Have you ever wondered how to dynamically instantiate Kubernetes resources before deploying them to a cluster? What if I tell you there is an easy way to do it? Sveltos lets you define add-ons and applications using templates. Before deploying any resource down the managed clusters, Sveltos instantiates the templates using information gathered from the management cluster.

In a previous post, we outlined a step-by-step approach to forming a Cilium cluster mesh between two clusters. In today's post, we will demonstrate how the Sveltos templating is used to deploy a Cilium cluster mesh dynamically in one go.

title image reading "Sveltos Templating Cilium"

Rancher RKE2 Cluster on Azure

· 9 min read
Eleni Grosdouli
DevOps Consulting Engineer at Cisco Systems

Introduction

For the last couple of days, I have been working on a new use case installing RKE2 clusters powered with Cilium on Azure Cloud. The requirement at hand was to use a Rancher instance and from there start deploying RKE2 clusters. After going through the official Rancher documentation, I have noticed that the instructions provided to pre-configure Azure Cloud are outdated.

In today's blog post, we will cover all the required steps taken to configure the Azure cloud-free credits to deploy RKE2 clusters with Cilium in that environment. Additionally, we will cover any limitations that come with the free credit concept.

title image reading "Rancher RKE2 Cluster on Azure"

Cilium Cluster Mesh on RKE2

· 11 min read
Eleni Grosdouli
DevOps Consulting Engineer at Cisco Systems

Introduction

After spending some time working with the on-prem RKE2 lab setup, I came to notice a couple of issues while forming in an automated fashion the Cilium cluster mesh between on-prem clusters.

In today's post, we will go through the step-by-step process of forming a Cilium Cluster Mesh and explain any issues that might have arisen by following the GitOps approach. The cilium CLI will not be required. The deployment will be performed primarily via Helm and kubectl.

Cilium on EKS with Sveltos

· 9 min read
Eleni Grosdouli
DevOps Consulting Engineer at Cisco Systems

Introduction

In today's blog post, we will demonstrate an easy way of deploying and controlling Cilium on an EKS cluster with Sveltos.

As the majority of the documentation out there provides a step-by-step installation directly with the Helm chart commands, we decided to demonstrate a different approach, the GitOps approach, with the use of Sveltos ClusterProfile CRD (Custom Resource Definition).

title image reading "Cilium on EKS with Sveltos Diagram"