SEPTEMBER 2022 GitOps for Kubernetes Essentials to Applications Hosted in Cloud-Native Ecosystems NINAD DESAI STAFF ENGINEER, INFRACLOUD CONTENTS • About GitOps for Kubernetes • Configuration Management Management in Kubernetes • GitOps for Kubernetes Essentials • Conclusion Git is the most widely used version control system, with more than 80 percent of its market share in today’s software industry running in Kubernetes. In this Refcard, we will dive into what GitOps means in the Kubernetes world, key principles, and the advantages for cloud-native ecosystems. ABOUT GITOPS FOR KUBERNETES Thanks

Contents 05 Foreword 07 Introduction 08 Chapter 1–What is GitOps? Origins in DevOps Kubernetes and containers Cloud-Native DevOps A DevOps Operating Model GitOps Principles Open Cluster Management Other GitOps Tools PipeCD Keptn Pulumi Kubernetes Operator Summary 18 Chapter 3–Templating Everything in Git Kustomize Helm Operators Structures Repositories Reflecting an Organizational Boundary Kubernetes Platform Administrator Kubernetes Application Developer Other Boundaries GitOps Repo Example

OpenShift GitOps 2 第 1 章 什么是 GITOPS？ GitOps 是为云原生应用程序实施持续部署的一种声明方式。您可以使用 GitOps 创建可重复进程，用于在 多集群 Kubernetes 环境间管理 OpenShift Container Platform 集群和应用程序。GitOps 以快速的速度处 理和自动化复杂部署，节省部署和发行周期期间的时间。 GitOps 工作 GitOps 是一个使用 Argo CD 作为声明性 GitOps 引擎的 Operator。它启用了多集群 OpenShift 和 Kubernetes 基础架构的 GitOps 工作流。使用 Red Hat OpenShift GitOps，管理员可以在 集群和开发生命周期中一致地配置和部署基于 Kubernetes 的基础架构和应用程序。Red Hat OpenShift GitOps 基于开源项目 ApplicationSet Controller (Argo CD ApplicationSet Controller) Argo CD 中存在并处理 ApplicationSet CR 的自定义 Kubernetes 控制器。此控制器会根据 ApplicationSet CR 的内容自动创建、更新和删除 Argo CD 应用程序。 AppProject CRD CRD 代表项目内应用程序的逻辑分组

点上运 运行 行 GITOPS CONTROL PLANE 工作 工作负载 负载 1.1. 将 GITOPS CONTROL PLANE 工作负载移到基础架构节点 1.2. 将 GITOPS OPERATOR POD 移到基础架构节点 1.3. 其他资源 3 3 4 6 目 目录 录 1 Red Hat OpenShift GitOps 1.13 基 基础 础架 架构节 构节点上的 点上的 Container Platform 在基础架构节点上运行 GitOps control plane 工作负载。默认 情况下，这包括 Operator pod 和由 openshift-gitops 命名空间中的 Red Hat OpenShift GitOps Operator 创建的 control plane 工作负载，包括此命名空间中的默认 Argo CD 实例。 使用 GitOps control 运行以下命令，将现有节点标记为基础架构： 2. 编辑 GitOpsService 自定义资源(CR)以添加基础架构节点选择器： $ oc label node node-role.kubernetes.io/infra= 第 第 1 章 章 在基 在基础 础架 架构节 构节点上 点上运 运行 行 GITOPS CONTROL PLANE 工作 工作负载 负载 3 3. 在 GitOpsService

Separation of Privileges 03 04 05 06 07 10 GitOps Hands On Tutorial Part 1: Spin up a Kubernetes Cluster Part 2: Fork the Sock Shop Repository Part 3: Setup CI and Connect a Container Registry your team can make changes and updates safely and securely to complex applications running in Kubernetes. Freedom of choice Because there is no single tool that can do everything required in your pipeline ship features. eBook 4 The Principles of GitOps The entire system is described declaratively. Kubernetes is just one example of many modern cloud native tools that are “declarative” and that can be treated

GitOps Second Demo What’s next? @rytswd #IstioCon Simply put, it is about combining multiple Kubernetes clusters. For example, UPSIDER currently has 4 clusters with Istio multicluster setup. Benefits Container Istio Sidecar Proxy Istio Ingress Gateway Istio Egress Gateway @rytswd Istio Operator istio-operator Manages Istio installation with IstioOperator Custom Resource Example ● Data Plane with @rytswd NOTE: This demo is based on Istio Version 1.7.5. KinD https://github.com/kubernetes-sigs/kind Version v0.10.0 Kubernetes v1.17.17 #IstioCon Goal of demo Target Audience What to expect Istio Multicluster

pull-requests” GitOps Benefits 5 GitOps is for Everyone Developers Operations Kubernetes Cluster Node 1 Kubernetes (K8s) is an open-source system for automating deployment, scaling, and management It is a resource scheduler KUBERNETES 101 6 Node Node Node Node Node Node Node Node 1 1 2 2 2 2 3 3 3 4 4 Applications OpenShift 4 - A Smarter Kubernetes Platform Automated, full-stack full-stack installation from the container host to application services Seamless Kubernetes deployment to any cloud or on-premises environment Autoscaling of cloud resources One-click updates for platform

companies. Introduction GitOps has gained popularity in the cloud-native ecosystem, particularly in Kubernetes-based environments, where managing infrastructure as code is crucial. Knowing the philosophy of reproducibility of deployments. GitOps is popular in the cloud-native ecosystem, particularly in Kubernetes-based environments, where managing infrastructure as code is crucial. Essential elements of GitOps architecture requires a GitOps operator, or agent, to evaluate both the infrastructure and application configuration in the repository to detect when the Kubernetes cluster resources should automatically

declaratively. The term GitOps was confined by Weaveworks in 2017 and was primarily aimed at managing Kubernetes deployments. However, now it has evolved into supporting other infrastructure management solutions (Learn how to build a CI/CD pipeline.) The differentiating factor of a GitOps pipeline is the GitOps operator. This mechanism sits between the pipeline and the infrastructure platform, acting as a middleman communications between them. There are multiple available operators such as: Kubernetes Operator Terraform Cloud Operator Azure Service Operator Etc. GitOps workflow Now, we’ve got a Git repository and a properly

of our teams operate their software and systems and are managing their infrastructure including Kubernetes clusters on their own. [The] GitOps approach was the enabler so that even small teams can operate requirements. The team at Fidelity wanted the scalability and reliability that comes with adopting Kubernetes, and also sought to leverage the ecosystem of available cloud-native open source projects in order MediaMarktSaturn uses Flagger to automate canary releases in a GitOps pipeline. Whenever the GitOps operator, in their case, Flux, detects a new version, Flagger spins up a new canary release and shifts traffic