Architecting and Operating OpenShift Clusters : OpenShift for Infrastructure and Operations Teams

Front Matter ....Pages i-xvii The OpenShift Architecture (William Caban)....Pages 1-29 High Availability (William Caban)....Pages 31-54 Networking (William Caban)....Pages 55-76 Storage (William Caban)....Pages 77-98 Load Balancers (William Caban)....Pages 99-108 Deployment Architectures (William Caban)....Pages 109-167 Administration (William Caban)....Pages 169-193 Architecting OpenShift Jenkins Pipelines (William Caban)....Pages 195-220 Day-2 Operations (William Caban)....Pages 221-231 Advanced Network Operations (William Caban)....Pages 233-251 OCP 4.1 UPI Mode Bare-Metal with PXE Boot Deployment (William Caban)....Pages 253-280 Back Matter ....Pages 281-286 Table of Contents 5 About the Author 11 About the Technical Reviewer 12 Acknowledgments 13 Introduction 14 Chapter 1: The OpenShift Architecture 15 Linux Containers 15 Linux Container: Under the Hood 16 Container Specifications 19 Container Runtime and Kubernetes 21 Introduction to OpenShift Architecture Components 22 Kubernetes Constructs 23 OpenShift Constructs 30 Master Nodes 31 Infrastructure Nodes 34 App Nodes 35 OpenShift Consoles 36 OpenShift Routers 39 OpenShift Registry 43 Summary 43 Chapter 2: High Availability 44 Control Plane and Data Plane 44 HA for Control Plane 45 HA for ETCD 45 RAFT Consensus Algorithm 47 HA for Master Services 49 HA for OpenShift Consoles 57 HA for Logging, Metrics, and Monitoring 58 OpenShift Monitoring 59 Metrics 61 Metrics Server 63 Logging 64 HA for Data Plane 65 HA for OpenShift Router 66 HA for Container Registry 66 Summary 67 Chapter 3: Networking 68 East-West Traffic 69 OpenShift SDN 70 OpenShift ovs-subnet 75 OpenShift ovs-multitenant 76 OpenShift ovs-networkpolicy 78 Flannel 82 OpenShift with Third-Party SDN 84 OpenShift with Calico SDN 84 North-South Traffic 86 HAProxy Template Router 87 Summary 89 Chapter 4: Storage 90 OpenShift Storage 90 Kubernetes Storage Constructs 93 PersistentVolume Status 94 Reclaim Policy 95 Access Modes 95 OpenShift PersistentVolume Plugins 96 FlexVolume 97 With Master-Initiated Attach/Detach 99 Without Master-Initiated Attach/Detach 99 CSI 100 OpenShift Ephemeral 101 OpenShift Container Storage 102 OCS Converged Mode 103 Raw Disks for OCS Converged Mode 104 OCS Independent Mode 104 OCS Storage Provisioning 105 Storage Classes 106 OpenShift with Third-Party Storage 107 DriveScale Composable Platform 108 HPE 3PAR 108 HPE Nimble 109 NetApp Trident 109 OpenEBS (OSS, MayaData) 110 Summary 111 Chapter 5: Load Balancers 112 Load Balancer Overview 112 Load Balancer Considerations 113 Considerations for Master Nodes 113 Considerations for Infrastructure Nodes 114 Considerations for Specialized Protocols 117 Summary 121 Chapter 6: Deployment Architectures 122 Minishift 123 OCP 3.11 Deployment Architectures 125 Prerequisites 125 Operating System—Minimal Installation 127 General Requirements for the Cluster 127 SDN Subnets 128 (Optional) Subnets for Hosting Apps with Non-Web-Based or Specialized Protocols 128 Registry Service Account and Token 129 Activate and Assign OpenShift Subscriptions 129 Prepare OCP 3.11.x Installer on Bastion 130 Enable Password-less SSH 130 OpenShift Ansible Inventory File 130 Defining the OpenShift Release 131 Registry Definitions and Access 133 Red Hat OpenShift Container Storage 134 Web Console Access and Wildcard Apps Domain 135 Audit Logs 136 Configuring the SDN 136 Identity Providers 137 Cluster Monitoring (Prometheus) 138 Cluster Metrics (EFK Stack) and Logging 139 OpenShift Router and OpenShift Container Registry 140 OpenShift Service Catalog and Service Brokers 141 OpenShift Nodes 142 Sample Deployment Scenarios 143 Single Node Deployment (All-in-One) 144 Non-HA Control Plane Deployment 153 Full-HA Control Plane Deployment 155 Deploying OpenShift 167 Uninstalling OpenShift 167 Bastion Node as Admin Jumphost 168 OpenShift 4.x Deployments (AWS) 169 Prerequisites 169 OpenShift 4.x Deployment Architecture 170 OCP4 Deployment to AWS (IPI Mode) 170 Installing OCP4 on AWS 172 Standard Deployment 172 Customizing Standard Deployment 173 Deployment Progress 175 Configuring the Identity Provider 177 Summary 180 Chapter 7: Administration 181 User and Groups 181 Virtual Groups and Virtual Users 182 Authentication, Authorization, and OpenShift RBAC 183 RBAC 184 Default Cluster Roles 185 Security Context Constraints 186 SECCOMP Profiles 189 Enabling Unsafe SYSCTL 190 Identity Providers 191 Managing Users and Groups 193 Using Service Accounts 194 Quotas and Limit Ranges 196 OpenShift Service Catalogs 199 OpenShift Templates 200 Summary 205 Chapter 8: Architecting OpenShift Jenkins Pipelines 206 CI/CD Pipelines As a Service with OpenShift 206 Jenkins Pipeline Build Strategy 208 Creating the Pipeline BuildConfig 210 Deploying the Pipeline BuildConfig 213 Jenkinsfile with Source Code 219 Multiproject Pipelines 221 OpenShift Client Plugin 229 Custom Jenkins Images 229 Integrating External CI/CD Pipelines 231 Summary 231 Chapter 9: Day-2 Operations 232 Managing Leftover Objects 232 Garbage Collection 235 Node Optimizations 236 Node Resource Allocation 236 Setting Max Pods Per Node 237 Using the Tuned Profile 238 Eviction Policy 239 Pod Scheduling 240 Pod Priority 241 Summary 242 Chapter 10: Advanced Network Operations 243 Network Optimizations 243 Jumbo Frames and VXLAN Acceleration 243 Tuning Network Devices 245 Routing Optimizations 246 Route-Specific Optimizations Annotations 247 IP Whitelists 248 OpenShift Router Sharding 248 Supporting Non-HTTP/HTTPS/TLS Applications 249 Using IngressIP and ExternalIP 250 Using NodePorts and HostPorts 253 Multiple NIC per POD 254 OpenShift ServiceMesh 256 Summary 260 Chapter 11: OCP 4.1 UPI Mode Bare-Metal with PXE Boot Deployment 262 UPI Mode 262 Bare-Metal with PXE Boot Example 263 UPI Bare-Metal with PXE Boot 264 Prerequisites 264 DNS Configuration (Example) 265 Load Balancer Configuration (Examples) 268 DHCP with PXE Boot Configuration (Example) 273 PXE Boot Configuration (Example) 274 Preparing the Installation 275 Considerations with UPI Mode with PXE Boot 276 Downloading RHCOS and Installation Binaries 277 Preparing the PXE Boot Images 277 Installation 278 Creating the Configuration 279 Generating the Ignition Files 280 Bootstrap and Master Nodes 281 Worker Nodes 285 Summary 289 Index 290 Design and architect resilient OpenShift clusters and gain a keen understanding of how hundreds of projects are integrated into a powerful solution. While there are many OpenShift resources available for developers, this book focuses on the key elements of infrastructure and operations that teams need when looking to integrate and maintain this platform. You'll review important concepts, such as repeatable deployment techniques, advanced OpenShift RBAC capabilities, monitoring clusters, and integrating with external services. You'll also see how to run specialized workloads in OpenShift and how to deploy non-web based applications on the platform, all designed to help cultivate best practices as your organization continue evolve in microservices architectures. OpenShift has become the main enterprise Kubernetes distribution and its market penetration continues to growth at rapid rate. While OpenShift’s documentation provides a great list of configuration options to work with the platform, it can be a daunting task to wade through. __Architecting and Operating OpenShift Clusters__ breaks this content down into clear and useful concepts to provide you with a solid understanding of the OpenShift internal architecture. **What You'll Learn** * Operate high availability in muti-tenant OCP clusters Understand OpenShift SDN models, capabilities, and storage classes * Integrate OCP with existing data center capabilities and CI/CD pipelines * Support advanced capabilities like: Istio, Multus, Kubernetes Operators, hybrid deployments **Who This Book Is For** Cloud architects, OpenShift cluster administrators, and teams supporting developers in OpenShift environments who have a basic understanding of this platform and microservices architectures.