Openshift Flashcards
Openshift Interview Questions
What is OpenShift online
It is public PaaS of OpenShift community using which one can build and deploy its application on public cloud. It is red hat hosting platform
What is OpenShift ?
OpenShift is a cloud development Platform as a Service.It is an open source development platform by which developer develops and deploys application on cloud
What is OpenShift container registry ?
Its an inbuilt storage that is used to store Docker images.
What is Routes in OpenShift?
In OpenShift Routes is a way to externalize the services by providing externally reachable hostname.In OpenShift routes are created using routers developed by admin
How API are authenticated in OpenShift ?
In OpenShift master has inbuilt OAuth server which generates tokens that can be used for API authentication.
What type of build strategies are used in OpenShift?
- Docker Strategy
- Custom Strategy
- Pipeline Strategy
- Source-to-image Strategy
What is Source-to-image Strategy ?
In this from source code images are created.In Source-to-image strategy source code is downloaded and compiled and deployed in same container.From same code image is created
What are the identity providers in OAuth?
- HTPassword (Configure the htpasswd identity provider to validate user names and passwords against a flat file generated using htpasswd.)
- LDAP
- Basic Authentication
- GitHub
- OpenID Connect
What is Downward API in OpenShift?
The Downward API is a mechanism whereby pods can retrieve their metadata without having to call into the Kubernetes API. The following metadata can be retrieved and used to configure the running pods:
- Labels
- Annotations
- Pod name, namespace, and IP address
- Pod CPU/memory request and limit information
- Certain information can be mounted into the pod as an environment variable,whereas other information can be accessed as files within a volume.
What is Build Configurations?
Builds are configured and controlled by build configuration resources. Build configurations contain the details of the chosen build strategy as well as the source of the developer-supplied artifacts such as Git location, the details of the builder image to be used, and the output image.
How to run Openshift on AWS?
Using Red Hat OpenShift Service on AWS (ROSA)
Prerequisites:
- An AWS account.
- A Red Hat account to access OpenShift services.
Installer-Provisioned Infrastructure (IPI)
Prerequisites:
- An AWS account with permissions to create resources.
- A valid OpenShift pull secret from the Red Hat OpenShift Cluster Manager.
User-Provisioned Infrastructure (UPI)
Prerequisites:
Similar to IPI but requires more manual setup of infrastructure
How Openshift integrate with AWS service using Red Hat OpenShift Service on AWS (ROSA)
Deployment Options
AWS-Specific Services
OpenShift on AWS can leverage AWS-specific services like Amazon RDS for databases, S3 for storage, and Route 53 for DNS management. Other cloud providers may offer similar services but with different integrations and capabilities
Managed Service
Availability:
The Red Hat OpenShift Service on AWS (ROSA) is a fully managed service that simplifies installation and management, which may not be as streamlined on other platforms without similar managed offerings
While install Openshift on AWS, what’s a difference in ROSA and other installation method like IPI and UPI
Infrastructure Management
## Control Plane Management
In ROSA, Red Hat manages the control plane, allowing users to focus on application deployment rather than infrastructure management. In contrast, on other platforms or in self-managed installations (like IPI or UPI), users may need to configure and manage the control plane themselves
How to run Openshift on Azure
Using Azure Red Hat OpenShift (ARO)
Prerequisites:
- An Azure account with sufficient permissions.
- A Red Hat account for accessing OpenShift services.
Manual Installation Using OpenShift Installer
How are build-in operators available in OpenShift
All the Openshift components are installed via the Operators
Several common ones are
1. OpenShift GitOps Operator
- Utilizes Argo CD for managing infrastructure and application configurations using GitOps principles. It allows for the creation of templates for common configurations and automates synchronization with secrets managers.
-
Service Mesh Operator
- Based on the Istio project, this Operator helps manage the communication between microservices in a distributed application. It enables service discovery, load balancing, authentication, and monitoring, making it easier to manage complex application architectures[1].
-
OpenShift Pipelines Operator
- Implements CI/CD capabilities within OpenShift by providing tools for building, deploying, and managing pipelines[1].
-
OpenShift API for Data Protection (OADP) Operator
- Leverages the Velero project to facilitate backup and restore operations for applications running on OpenShift. It is designed to handle the specific needs of OpenShift environments[1].
-
Elasticsearch Operator
- Automates the deployment and management of Elasticsearch clusters within OpenShift, ensuring that they are configured correctly and can scale as needed
-
Prometheus Operator
- Simplifies the deployment and management of Prometheus monitoring instances, allowing users to easily monitor their applications and infrastructure
