Openshift Interview Questions For Freshers & Experienced

  • Question 1) Explain what is openshift? Why it is used?
  • Question 2) Enlist few openshift alternatives?
  • Question 3) Explain the components of OpenShift?
  • Question 4) List major features of OpenShift?
  • Question 5) What is System Requirement to install OpenShift?
  • Question 6) List different OpenShift types?
  • Question 7) Is openshift paas or iaas?
  • Question 8) What is difference between openshift and kubernetes?
  • Question 9) What is OpenShift CLI?
  • Question 10) What are stateful Pods?
  • Question 11) Explain what are labels in OpenShift?
  • Question 12) What is a gear in Openshift?
  • Question 13) What is OpenShift Origin?
  • Sharad Jaiswal
  • 31st Dec, 2018
  • 1071 Followers

Openshift Interview Questions
Updated ON

31st Dec, 2018

No. of Questions

15

Posted In

Others

Author

Sharad Jaiswal

Openshift Interview Questions

Q1. Explain what is openshift? Why it is used?

Open shift is a cloud development platform that is developed by the Red Hat, it is released in the year 2011.

The best thing about Open shift is that it provides free & en source cloud-based platform. OpenShift is a free software itself. You can run on your server. Exactly like WordPress dot ORG's WordPress software OR you can use their limited Free Service. WordPress dot COM.

The main reason for using the Open Shift is the wide range of benefits, some of them are listed below:-

  • Innovate and go to market faster
  • Accelerate application development
  • Enterprise-grade, container-based platform with no vendor lock-in
  • Enable DevOps and department-wide collaboration
  • Self-service provisioning

Q2. Enlist few openshift alternatives?

There are eight alternatives of open shift which are given below:-

  • Clever Cloud:- It is the best IT-Automation platform basically used for the continuous integration & deployment .
  • Amazon Web Services :- AWS is a comprehensive, easy to use computing platform offered Amazon. The platform is developed with a combination of infrastructure as a service (IaaS), platform as a service (PaaS) and packaged software as a service (SaaS) offerings.
  • Google App Engine:- Google App engine is developed by the google in Apri 7,2008 . It performs the cloud computing platform for developing & hosting web application.
  • SAP HANA:- It is RDBMS(Relational Database Management System) deveoped by SAP SE in 2010. Storing data in main memory rather than on disk provides faster data access and, by extension, faster querying and processing.
  • Oracle Cloud PaaS:- It is comprehensive & Standard-based, and built on Oracle and open-source technologies that integrate with your existing applications, regardless of origin.
  • Heroku:- It is the container-based cloud Platform as a Service (PaaS), flexible, and easy to use, offering developers the simplest path to getting their apps to market.
  • Engine Yard:- Engine Yard was founded in 2006 by Tom Mornini, Ezra Zygmuntowicz, Lance Walley and Jayson Vantuyl. It is a platform as a service (PaaS) provider that automates, configures and deploys applications in the cloud.
  • vCloud Air:- It supports the concept of regions - or locations, in vCloud terminology - which are typically used for better pricing, to increase application performance or as disaster recovery.

Q3. Explain the components of OpenShift?

There are many components of Openshift few of them are given below :-

  • Docker(docker.service):- It is the set of Paas products . It has 3 components i.e., Software, Objects, Registeries. It is a required dependency of all openshift* packages and therefore should be active and enabled on all hosts.
  • OpenVSwitch(openvswitch.service):- It is the OpenShift SDN is packaged as part of the OpenShift Node component (below) not with OVS & it is required in every host in order to support the OpenShift SDN.
  • Etcd(etcd.service):- In Etcd there is a must condition that it requires at least 3 active cluster members. Hence the components of Etcd is split out into its own services.
  • OpenShift master(atomic-openshift-master OR atomic-openshift-master-api and atomic-openshift-master-controllers depending on HA Configuration):- In this Openshift master all master nodes are bundled together in a single service.
  • Openshift node (atomic-openshift-node.service):- Any node can technically be labeled as a master node, infrastructure node, application node, or any combination of the two. The specific technique depends on the specific version of OpenShift v3.x

Q4. List major features of OpenShift?

The major features of OpenShift are:-

  • Innovate and go to market faster
  • Accelerate application development
  • Enterprise-grade, container-based platform with no vendor lock-in
  • Enable DevOps and department-wide collaboration
  • Self-service provisioning

Q5. What is System Requirement to install OpenShift?

The system requirement is different for both Masters & Nodes.

The system Required of masters are:-

  • Minimum 8 GB RAM
  • Minimum 30 GB hard disk space
  • 2 vCPU
  • Base OS
  • Physical & virtual system

The system Required of Nodes are:-

  • Minimum 8 GB RAM
  • Minimum 15 GB hard disk space
  • 1 vCPU
  • Docker 1.6.2 or later
  • Base OS

Q6. List different OpenShift types?

Open shift has 3 major versions:-

  • OpenShift Origin:- It is Open source or community addition version of Openshift.
  • OpenShift Online:- It is a pubic PaaS as a service hosted on AWS.
  • OpenShift Enterprise:- The best thing about enterprise, it has vendor licenses

Q7. Is openshift paas or iaas?

PaaS in Openshift –

To Build Platform as a Service is where access to a cloud-based environment is provided by a service provider, enabling application development and other cloud computing solutions. In PaaS, users receive a platform (runtime) and environment.

IaaS in Openshift –

To Host Infrastructure as a Service refers to access to storage, networking, servers and other cloud computing resources, offered to a business by a vendor. In IaaS, users are provided with a ‘virtual server’ on which they can host their applications and data.

Q8. What is difference between openshift and kubernetes?

Diffrence between Openshift and Kubernetes

OpenShift Origin would be the best choice for scenarios where there is no existing tooling and the user needs to focus on his application code while using everything else available from an out-of-the-box set of tools present within the platform. Here the user maintains his code while other complexities of application lifecycle management, orchestration, routing between services etc are handled by the platform.

Kubernetes is a good implementation choice for use cases where a user has specific requirements for tooling and getting the latest release is important to leverage new features. However, the installation process can get a little complex compared to other options. Additionally, the user needs to have in-house expertise to handle aspects such as access control, logging, monitoring, application lifecycle etc.

Q9. What is OpenShift CLI?

OpenShift CLI has the capability to manage end-to-end application life cycle. It is used for managing the mantaining OenShift applications from command line.

OpenShift CLI is capable of performing all basic and advance configuration, management, addition, and deployment of applications.

The basic OC commands are:-

  • Types
  • Login 
  • new-project 
  • new-app 
  • Status 
  • Project 
  • Projects 
  • Explain 
  • Cluster

Q10. What are stateful Pods?

It has the unique ordinal index & a stable network identity.

StatefulSets requires some application given below:-

  • Stable, unique network identifiers. 
  • Stable, persistent storage. 
  • Ordered, graceful deployment and scaling. 
  • Ordered, graceful deletion and termination. 
  • Ordered, automated rolling updates.

Q11. Explain what are labels in OpenShift?

Labels are the key values attached to objects, such as pods. Labels are intended to be used to specify identifying attributes of objects that are meaningful and relevant to users, but do not directly imply semantics to the core system.

Each object can have a set of key/value labels defined. Each Key must be unique for a given object.

"metadata": {
  "labels": {
    "key1" : "value1",
    "key2" : "value2"
  }
}

There are many operations in lables in OpenShift but we consider two of them as the important one:-

  • add a label
  • remove a label

Q12. What is a gear in Openshift?

Gears were a core component of OpenShift v2. Technologies such as kernel namespaces, cGroups, and SELinux helped deliver a highly-scalable, secure, containerized application platform to OpenShift users. Gears themselves were a form of container technology.

Gears can be thought of as equivalents to "web workers" however gears is better described as a unit (collection of resources).

In the OpenShift free tier you only have small gears (512MB memory, 1GB HDD, etc.) So the small gear is a unit of resources that you have for you to use.

Q13. What is OpenShift Origin?

OpenShift Origin is the open source community version of OpenShift Enterprise. In order to understand what this means, you need to understand what open source software is - computer software developed via a competitive collaborative model from many individual sources. Origin updates as often as open source developers contribute via git, a version control system, sometimes as often as several times per week.

Q14. What is Source-to-Image (S2I)?

Source-to-image (S2I) is used for building container images for application in a fast, flexible, and reproducible way.

S2I provides a easy solution for the challenge of build reproducibility, for applications written in any programming language.

The real beauty of S2I, in my opinion, is the ability to use builder images as templates, so that similar applications with similar configurations can be deployed without managing configuration files like Dockerfiles for every application—providing identical, reproducible environments for similar applications.

S2I supports incremental builds, which re-use previously downloaded dependencies, previously built artifacts, etc.

The advantages of S2I are:-

  • Image flexibility
  • Speed 
  • Patchability 
  • Operational Efficiency 
  • User Efficiency 
  • Ecosystem 
  • Reproducibility

Q15. What is OKD?

OKD is a container management and orchestration platform based on Docker and Kubernetes.

OKD is a complete solution to manage, deploy, and operate containerized applications that (in addition to the features provided by Kubernetes) includes an easy-to-use web interface, automated build tools, routing capabilities, and monitoring and logging aggregation features.

OKD provides several deployment options aimed at different requirements with single or multiple master nodes, high-availability capabilities, logging, monitoring, and more.

About Author :

  • Author of Openshift Interview Questions

    Sharad Jaiswal

    Sharad Jaiswal is Sr. Web Developer from Noida area. He have rich experience in PHP, Angular Js, React, javascript and Node .If you any query or project on these programming you can drop your enquiry in comment section.

Leave A Comment :

Valid name is required.

Valid name is required.

Valid email id is required.