What Is Openshift?
OpenShift is a cloud development Platform as a Service (PaaS) hosted by Red Hat. It’s an open source technology which helps organizations move their traditional application infrastructure and platform from physical, virtual mediums to the cloud. It supports a very large different of applications, which can be easily developed and deployed on OpenShift cloud platform.
Why Use Open Shift?
OpenShift provides a common platform for enterprise units to host their applications on cloud without worrying about the underlying operating system. This makes it very easy to use, develop, and deploy applications on cloud. One of the key features is, it provides managed hardware and network resources for all kinds of development and testing. With OpenShift, PaaS developer has the freedom to design their required environment with specifications.
What are the features of OpenShift?
You can find this entry as one of the most frequently asked OpenShift interview questions. The features of OpenShift include a rich command-line toolset, support for multiple databases and language, and an extensible cartridge system. The other features of OpenShift include the following.
- Multi-Environment support.
- One-click deployment.
- Responsive web console.
- Remote application debugging.
- Standardized workflow for developers.
- Rest API support.
- Support for remote SSH login to the application.
- In-built database services.
- Automatic application scaling.
- The facility of support for release management and continuous integration.
- IDE integration.
What is the Downward API in OpenShift?
Candidates could find this entry among frequently asked OpenShift interview questions. Downward API is a mechanism for pods to retrieve metadata without the need to call into Kubernetes API. Downward API is ideal for retrieving metadata and configuration of running pods.
The metadata which Downward API can retrieve include labels, annotations, pod name, namespace, and IP address. Downward API can also retrieve information about Pod CPU or memory requests and limits. Downward API may mount certain information on the pod as an environment variable. On the other hand, certain information could also be accessed as files within a volume.
What Is Openshift Origin?
OpenShift Origin is the upstream community project used in OpenShift Online, OpenShift Dedicated, and OpenShift Container Platform. Built around a core of Docker container packaging and Kubernetes container cluster management, Origin is augmented by application lifecycle management functionality and DevOps tooling. Origin provides an open source application container platform. All source code for the Origin project is available under the Apache License (Version 2.0) on GitHub.
What Is Openshift Online?
OpenShift Online is Red Hat’s public cloud application development and hosting service. It is an offering of OpenShift community using which one can quickly build, deploy, and scale containerized applications on the public cloud. It is Red Hat’s public cloud application development and hosting platform, which enables automated provisioning, management and scaling of application which helps the developer focus on writing application logic.
Explain Openshift Dedicated?
OpenShift Dedicated is Red Hat’s managed private cluster offering, built around a core of application containers powered by Docker, with orchestration and management provided by Kubernetes, on a foundation of Red Hat Enterprise Linux. It’s available on the Amazon Web Services (AWS) and Google Cloud Platform (GCP) marketplaces.
What Is Openshift Enterprise?
OpenShift Enterprise by Red Hat is a Platform as a Service (PaaS) that provides developers and IT organizations with an auto-scaling, cloud application platform for deploying new applications on secure, scalable resources with minimal configuration and management overhead. OpenShift Enterprise supports a wide selection of programming languages and frameworks, such as Java, Ruby, and PHP. Integrated developer tools, such as Eclipse integration, JBoss Developer Studio, and Jenkins, support the application life cycle.
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.
What Is Openshift Container?
OpenShift Container Platform (formerly known as OpenShift Enterprise) is Red Hat’s on-premises private platform as a service product, built around a core of application containers powered by Docker, with orchestration and management provided by Kubernetes, on a foundation of Red Hat Enterprise Linux.
What Is Pod?
A pod is collection of containers and its storage inside a node of a Kubernetes cluster. It is possible to create a pod with multiple containers inside it. Following is an example of keeping a database container and web interface container in the same pod.
What Are Deployment Strategies?
A deployment strategy is a way to change or upgrade an application. The aim is to make the change without downtime in a way that the user barely notices the improvements. The most common strategy is to use a blue-green deployment. The new version (the blue version) is brought up for testing and evaluation, while the users still use the stable version (the green version). When ready, the users are switched to the blue version. If a problem arises, you can switch back to the green version.
Define the OpenShift CLI.
Candidates should note the importance of CLI to form an OpenShift interview question. OpenShift CLI is a tool for the management of OpenShift applications from the command line. The OpenShift CLI provides abilities for the management of the end-to-end application lifecycle. It has the features for basic and advanced configuration for applications. Also, it includes functionalities for management, deployment, and adding applications.
What the systems on the OpenShift environment running on AWS?
The OpenShift environment running on Amazon Web Services includes one master node and one infrastructure node. It also includes an NFS server and 24 application nodes.
What type of security controls can you find on OpenShift?
OpenShift interview questions would also revolve around security concerns. The security policy of OpenShift follows certain precedents. Containers could not access host resources or run privileged. Containers have to run as non-root unique users separate from other users. Containers get CPU and memory limits according to definitions by the system administrator. Most important of all, regular users and admins could not change security quotas.
Do you know about OpenShift cartridges?
OpenShift cartridges have also popped up as an important OpenShift interview question. OpenShift cartridges are central points for developing applications. Every cartridge has specific libraries, build mechanisms, source code, routing logic, and connection logic alongside pre-configured environment. All these factors help in running your application.
What is the difference between gear and container?
You can find the latest OpenShift interview questions focused on difference-based evaluations. The terms ‘container’ and ‘gear’ are interchangeable. Containers have a precise mapping involving one-to-one relations among images. However, in the case of gears, many cartridges can become part of a single gear. In the case of containers, pods fulfill the collocation concept.
How OpenShift uses Docker and Kubernetes?
Kubernetes and Docker could work OpenShift in the form of a control system. You can find this question among the latest OpenShift interview questions commonly. The control system helps in enabling many deployment pipelines that are ideal for later use in auto-scaling, testing, and other processes.
What are the build strategies in OpenShift?
The common build strategies in OpenShift are
Docker strategy, custom strategy, Source to Image strategy, and pipeline
strategy.
What are the unique components you can find in OpenShift as compared to Kubernetes?
The components unique to OpenShift in comparison to Kubernetes are the Internal registry and Router as an ingress traffic control.
What is Volume Security?
Volume Security is ideal for the security of PV
and PVC projects in OpenShift. Controlling access to volumes in OpenShift
involves four main sections. The sections are Supplemental groups, fsGroup,
seLinuxOptions, and runAsUser.
What do you know about the OpenShift pipeline?
OpenShift pipeline is a tool for obtaining control over developing, deployment, and promotion of applications on OpenShift. OpenShift pipeline depends considerably on the Jenkins Pipeline Build Strategy, OpenShift Domain Specific Language (DSL), and Jenkins files.
Define Authentication In Openshift?
In OpenShift master has inbuilt OAuth server which generates tokens that can be used for API authentication.