20 Cloud Computing Interview Questions for Freshers

Cloud fundamentals interview questions

1. What is cloud computing?

Cloud computing provides computing resources such as servers, storage, databases and networking as services. Users can provision resources when needed and pay according to the provider’s pricing model instead of owning all underlying hardware. A complete answer should also mention responsibility: the provider manages part of the stack, while the customer still configures workloads, access and data protection.

2. What is the difference between IaaS, PaaS and SaaS?

IaaS provides infrastructure building blocks such as virtual machines, networks and storage, leaving more operating-system and application management to the customer. PaaS manages more of the runtime so developers focus on deploying applications. SaaS provides a finished application to end users. The models differ mainly in what the provider manages and what the customer controls.

3. What are public, private, hybrid and multi-cloud models?

Public cloud uses services operated by an external provider. Private cloud is dedicated to one organization. Hybrid cloud connects cloud resources with private or on-premises systems. Multi-cloud means using services from more than one cloud provider. Hybrid describes connected environments; multi-cloud describes provider choice, so they answer different questions.

4. What are regions and availability zones?

A region is a geographic area where a provider operates infrastructure. Availability zones are separate locations within a region designed to reduce correlated failure. Deploying across zones can improve resilience, but it does not automatically make an application highly available; load distribution, data replication, health checks and tested recovery still matter.

5. What is the shared responsibility model?

The provider secures and operates the underlying cloud infrastructure, while the customer remains responsible for areas such as data, identities, permissions and workload configuration. The exact boundary changes with IaaS, PaaS and SaaS. Use the shared responsibility guide to practise service-specific examples.

Compute and storage interview questions

6. What is a virtual machine?

A virtual machine is an isolated computing environment with allocated CPU, memory, storage and an operating system. In cloud platforms you select an image and size, configure network access and manage the guest system according to the service agreement. A VM that exists is not necessarily reachable; routes, firewalls, credentials and service status all matter.

7. How is a container different from a virtual machine?

A VM includes a complete guest operating system. Containers share the host kernel and package an application with its dependencies, so they are usually lighter and start faster. Containers do not remove the need for security, networking, persistent storage, monitoring or orchestration.

8. When would you use object, block or file storage?

Object storage fits files addressed as objects, such as images, backups and static assets. Block storage provides disk-like volumes commonly attached to compute instances. File storage provides a shared directory structure. The choice depends on access pattern, latency, sharing, durability and application compatibility.

9. What is scalability, and how is it different from availability?

Scalability is the ability to handle changing demand by adding or adjusting resources. Availability is the ability to keep serving users despite faults or maintenance. Scaling can contribute to availability, but redundancy, health checks, failover and data design are also required.

Cloud networking interview questions

10. What is a VPC or virtual network?

It is a logically isolated network boundary in a cloud platform. You define address ranges and subnets, then use routes and traffic controls to connect resources. Read the cloud networking fundamentals guide for a request-path explanation.

11. What is the difference between a public and private subnet?

A public subnet has a route that can support direct internet connectivity for appropriately configured resources. A private subnet does not provide that direct inbound path. A resource also needs suitable addressing and traffic rules, so a subnet name alone does not make something public or secure.

12. What does a route table do?

A route table matches destination ranges to next hops. It determines where packets should go, such as within the virtual network, towards an internet gateway, through a NAT service or to another connected network. It does not replace firewall rules or identity permissions.

13. What is the purpose of a load balancer?

A load balancer accepts traffic and distributes it across healthy targets. Health checks help avoid sending requests to unhealthy instances. A load balancer can improve availability and scaling, but the application and data layers must also handle multiple targets correctly.

Security and operations interview questions

14. What is least privilege?

Least privilege means granting only the permissions needed for a task and only for the necessary period. Prefer role-based temporary access where possible, require multi-factor authentication for sensitive accounts and review permissions as responsibilities change.

15. What is the difference between authentication and authorization?

Authentication verifies who or what is making a request. Authorization determines which actions that identity may perform. A successful login does not mean the identity may read every storage object or modify every network.

16. What are metrics, logs and alerts?

Metrics are numerical measurements over time, such as CPU utilization or request latency. Logs record events and contextual details. Alerts evaluate selected conditions and notify or trigger action. Troubleshooting often starts with a symptom, uses metrics to narrow the time and component, then uses logs for detail.

17. How would you troubleshoot an unreachable cloud virtual machine?

First define the symptom: timeout, refused connection or authentication failure. Confirm the instance is running and the expected service is listening. Check the destination address, DNS, routes, public/private path and network rules. Then check operating-system firewall settings and credentials. Change one thing at a time and record the evidence.

18. How would you investigate an access-denied error on cloud storage?

Identify the requesting identity, requested action and target resource. Review identity policies, resource policies, ownership and any explicit deny. Confirm encryption-key permission if applicable. Avoid making the storage public as a shortcut; use audit logs or policy simulation tools when available.

19. How do you control cloud costs during practice?

Choose small resources, set budgets and alerts, review usage and remove resources after the exercise. Check disks, snapshots, public addresses and managed services as well as virtual machines. Budget alerts improve visibility but may not automatically stop resources.

20. Explain one cloud project you completed.

Use a clear sequence: problem, architecture, your actions, tests, issue encountered, evidence used, result and cleanup. Mention access controls and cost awareness. Do not call a tutorial a production client project; explain what you personally configured and learned.

How to practise these answers

Do not memorise a paragraph word for word. Draw a small architecture and attach each concept to it. For example, trace a user request through DNS and a load balancer to a virtual machine, then describe how the application reaches private data and which logs you would inspect after a failure.

Prepare two short versions of each answer: a 30-second definition and a two-minute scenario. If the interviewer asks about a provider-specific service, translate the common concept into the platform you studied without pretending that AWS and Azure settings are identical.

Project-answer checklist for freshers

• State the problem and intended user outcome.
• Draw the components and traffic path.
• Explain your service and access-control choices.
• Describe one permitted test and one failure test.
• Show which metric or log supported your conclusion.
• Explain cleanup, cost control and project limitations.

If you want guided practice around these foundations, review the cloud computing course in Vizag and Visakhapatnam. Use the course for broad concepts, and use the separate AWS or Azure pages only when you choose a deeper platform track.

Frequently asked questions