Health Check - Deploying an application | Tutorials | Red Hat OpenShift Service on AWS

About
- Welcome
- Learn more about ROSA with HCP
- AWS STS and ROSA with HCP explained
- Legal notice
What's new
- What's new with Red Hat OpenShift Service on AWS
Introduction to ROSA
- Understanding ROSA
- Policies and service definition
- About IAM resources for ROSA with STS
- OpenID Connect Overview
Architecture
- Architecture overview
- Product architecture
- Architecture models
- Control plane architecture
- NVIDIA GPU architecture overview
- Understanding OpenShift development
- Admission plugins
Tutorials
- Tutorials overview
- ROSA with HCP activation and account linking
- ROSA with HCP private offer acceptance and sharing
- Verifying Permissions for a ROSA STS Deployment
- Deploying ROSA with a Custom DNS Resolver
- Using AWS WAF and Amazon CloudFront to protect ROSA workloads
- Using AWS WAF and AWS ALBs to protect ROSA workloads
- Deploying OpenShift API for Data Protection on a ROSA cluster
- AWS Load Balancer Operator on ROSA
- Configuring Microsoft Entra ID (formerly Azure Active Directory) as an identity provider
- Using AWS Secrets Manager CSI on ROSA with STS
- Using AWS Controllers for Kubernetes on ROSA
- Deploying the External DNS Operator on ROSA
- Dynamically issuing certificates using the cert-manager Operator on ROSA
- Assigning consistent egress IP for external traffic
- Updating component routes with custom domains and TLS certificates
- Getting started with ROSA
- Deploying an application
Getting started
- ROSA quickstart guide
- Comprehensive guide to getting started with ROSA
- Understanding the ROSA with STS deployment workflow
Prepare your environment
- Prerequisites checklist for deploying ROSA using STS
- Detailed requirements for deploying ROSA using STS
- ROSA IAM role resources
- Limits and scalability
- ROSA with HCP limits and scalability
- Planning your environment
- Required AWS service quotas
- Setting up your environment
Install ROSA with HCP clusters
- Creating ROSA with HCP clusters using the default options
- Creating a ROSA cluster using Terraform
  - Creating a default ROSA cluster using Terraform
- Creating ROSA with HCP clusters using a custom AWS KMS encryption key
- Creating a private cluster on ROSA with HCP
- Creating ROSA with HCP clusters with external authentication
- Creating ROSA with HCP clusters without a CNI plugin
- Deleting a ROSA with HCP cluster
Install ROSA Classic clusters
- Creating a ROSA cluster with STS using the default options
- Creating a ROSA cluster with STS using customizations
- Creating a ROSA (classic architecture) cluster using Terraform
  - Creating a default ROSA (classic architecture) cluster using Terraform
- Interactive cluster creation mode reference
- Creating an AWS PrivateLink cluster on ROSA
- Configuring a shared virtual private cloud for ROSA clusters
- Accessing a ROSA cluster
- Configuring identity providers using Red Hat OpenShift Cluster Manager
- Revoking access to a ROSA cluster
- Deleting a ROSA cluster
- Deploying ROSA without AWS STS
Support
- Support overview
- Managing your cluster resources
- Approved Access
- Getting support
- Remote health monitoring with connected clusters
- Gathering data about your cluster
- Summarizing cluster specifications
- Troubleshooting
Web console
- Web console overview
- Accessing the web console
- Viewing cluster information
- Dynamic plugins
- Web terminal
- About quick start tutorials
CLI tools
- CLI tools overview
- OpenShift CLI (oc)
- Developer CLI (odo)
- Knative CLI (kn) for use with OpenShift Serverless
- Pipelines CLI (tkn)
- opm CLI
  - Installing the opm CLI
  - opm CLI reference
- Operator SDK
  - Installing the Operator SDK CLI
  - Operator SDK CLI reference
- ROSA CLI
Red Hat OpenShift Cluster Manager
- Red Hat OpenShift Cluster Manager
Cluster administration
- Cluster notifications
- Configuring private connections
- Cluster autoscaling
- Manage nodes using machine pools
- Configuring PID limits
Security and compliance
- Viewing audit logs
- Adding additional constraints for IP-based AWS role assumption
Authentication and authorization
- Authentication and authorization overview
- Understanding authentication
- Managing user-owned OAuth access tokens
- Configuring identity providers
- Using RBAC to define and apply permissions
- Understanding and creating service accounts
- Using service accounts in applications
- Using a service account as an OAuth client
- Assuming an AWS IAM role for a service account
- Scoping tokens
- Using bound service account tokens
- Managing security context constraints
- Understanding and managing pod security admission
- Syncing LDAP groups
Upgrading
- Upgrading ROSA with HCP clusters
- Upgrading ROSA Classic clusters
CI/CD
- CI/CD overview
  - About CI/CD
- Builds using BuildConfig
- Jenkins
Images
- Overview of images
- Overview of the Cluster Samples Operator
- Using the Cluster Samples Operator with an alternate registry
- Creating images
- Managing images
- Managing image streams
- Using image streams with Kubernetes resources
- Triggering updates on image stream changes
- Image configuration resources (Classic)
- Image configuration resources (HCP)
- Using templates
- Using Ruby on Rails
- Using images
Add-on services
- Adding services to a cluster
- Available services
Storage
- Storage overview
- Understanding ephemeral storage
- Understanding persistent storage
- Configuring persistent storage
  - Persistent storage using AWS Elastic Block Store
- Using Container Storage Interface (CSI)
- Generic ephemeral volumes
- Dynamic provisioning
Registry
- Registry overview
- Image Registry Operator in Red Hat OpenShift Service on AWS
- Accessing the registry
Operators
- Operators overview
- Understanding Operators
- User tasks
  - Creating applications from installed Operators
- Administrator tasks
- Developing Operators
Networking
- About networking
- Networking Operators
- Network verification
- Configuring a cluster-wide proxy during installation
- CIDR range definitions
- Network security
- OVN-Kubernetes network plugin
  - About the OVN-Kubernetes network plugin
  - Configuring an egress IP address
- OpenShift SDN network plugin
  - Enabling multicast for a project
- Configuring Routes
  - Route configuration
  - Secured routes
Building applications
- Building applications overview
- Projects
  - Working with projects
  - Configuring project creation
- Creating applications
- Viewing application composition using the Topology view
- Working with Helm charts
- Deployments
- Quotas
  - Resource quotas per project
  - Resource quotas across multiple projects
- Using config maps with applications
- Monitoring project and application metrics using the Developer perspective
- Monitoring application health
- Editing applications
- Working with quotas
- Pruning objects to reclaim resources
- Idling applications
- Deleting applications
- Using the Red Hat Marketplace
Backing up and restoring applications
- Backing up applications
Nodes
- Overview of nodes
- Working with pods
- Automatically scaling pods with the Custom Metrics Autoscaler Operator
- Controlling pod placement onto nodes (scheduling)
- Using jobs and daemon sets
  - Running background tasks on nodes automatically with daemon sets
  - Running tasks in pods using jobs
- Working with nodes
- Working with containers
- Working with clusters
Observability
- Observability overview
  - About Observability
- Monitoring
- Logging
Service Mesh
- Service Mesh 2.x
Serverless
- About Serverless
  - Serverless overview
Virtualization
- About
- Getting started
  - Getting started with OpenShift Virtualization
  - virtctl and libguestfs
- Installing
- Post-installation configuration
- Updating
  - Updating OpenShift Virtualization
- Virtual machines
- Networking
- Storage
- Live migration
- Nodes
- Monitoring
- Support
- Backup and restore
  - Backup and restore by using VM snapshots
  - Backing up and restoring virtual machines

Preparing your desktop
Crashing the pod
Viewing the revived pod
Making the application malfunction

You can see how Kubernetes responds to pod failure by intentionally crashing your pod and making it unresponsive to the Kubernetes liveness probes.

Preparing your desktop

Split your desktop screen between the OpenShift web console and the OSToy application web console so that you can see the results of your actions immediately.

If you cannot split your screen, open the OSToy application web console in another tab so you can quickly switch to the OpenShift web console after activating the features in the application.
From the OpenShift web console, select Workloads > Deployments > ostoy-frontend to view the OSToy deployment.

Crashing the pod

From the OSToy application web console, click Home in the left menu, and enter a message in the Crash Pod box, for example, This is goodbye!.
Click Crash Pod.

The pod crashes and Kubernetes should restart the pod.

Viewing the revived pod

From the OpenShift web console, quickly switch to the Deployments screen. You will see that the pod turns yellow, meaning it is down. It should quickly revive and turn blue. The revival process happens quickly so you might miss it.