# Cloud Cost Optimization (DevOps)

> FinOps, cost monitoring, reserved instances, spot instances, resource tagging, waste reduction

- 20 interview questions
- Senior
- [Interview Questions: DevOps](https://sharpskill.dev/en/technologies/devops/interview-questions.md)

## 1. What is FinOps in the cloud context?

**Answer**

FinOps (Financial Operations) is a cultural practice that brings financial accountability to the variable cloud spending model, combining engineering, finance and business. This approach enables teams to make data-driven decisions about tradeoffs between speed, cost and quality. FinOps encourages collaboration between developers, finance and operations to optimize cloud business value.

## 2. What is the main difference between Reserved Instances (RI) and Savings Plans in AWS?

**Answer**

Reserved Instances require commitment to a specific instance type (family, size, region) for 1 or 3 years, offering up to 72% discount. Savings Plans are more flexible: they automatically apply to different instance families, sizes and regions, as long as usage respects an hourly spending commitment ($/hour). Savings Plans generally offer better operational flexibility for dynamic architectures.

## 3. When to use Spot Instances in AWS?

**Answer**

Spot Instances offer up to 90% discount but can be interrupted with only 2 minutes notice. They are ideal for interruption-tolerant workloads: batch processing, CI/CD builds, data analysis, ML training. It's recommended to combine Spot with Auto Scaling Groups and diversification strategies (multiple instance types/AZs) to maximize availability. Never use Spot for critical databases or stateful services without replication.

## 17 more questions available

- What is the main objective of resource tagging for cost optimization?
- How to identify and reduce zombie cloud resources?

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## Other DevOps interview topics

- [Version Control & Git](https://sharpskill.dev/en/technologies/devops/interview-questions/version-control-git.md): 20 questions, Junior
- [Linux Fundamentals](https://sharpskill.dev/en/technologies/devops/interview-questions/linux-fundamentals.md): 22 questions, Junior
- [Shell Scripting & Bash](https://sharpskill.dev/en/technologies/devops/interview-questions/shell-scripting-bash.md): 20 questions, Mid-Level
- [Networking Basics](https://sharpskill.dev/en/technologies/devops/interview-questions/networking-basics.md): 22 questions, Junior
- [Docker Fundamentals](https://sharpskill.dev/en/technologies/devops/interview-questions/docker-fundamentals.md): 24 questions, Junior
- [CI/CD Fundamentals](https://sharpskill.dev/en/technologies/devops/interview-questions/ci-cd-fundamentals.md): 18 questions, Junior
- [GitHub Actions](https://sharpskill.dev/en/technologies/devops/interview-questions/github-actions.md): 22 questions, Mid-Level
- [GitLab CI/CD](https://sharpskill.dev/en/technologies/devops/interview-questions/gitlab-ci.md): 22 questions, Mid-Level
- [Jenkins](https://sharpskill.dev/en/technologies/devops/interview-questions/jenkins.md): 22 questions, Mid-Level
- [Kubernetes Basics](https://sharpskill.dev/en/technologies/devops/interview-questions/kubernetes-basics.md): 26 questions, Mid-Level
- [Kubernetes Networking](https://sharpskill.dev/en/technologies/devops/interview-questions/kubernetes-networking.md): 24 questions, Mid-Level
- [Kubernetes Advanced](https://sharpskill.dev/en/technologies/devops/interview-questions/kubernetes-advanced.md): 24 questions, Mid-Level
- [Ingress & API Gateway](https://sharpskill.dev/en/technologies/devops/interview-questions/ingress-api-gateway.md): 20 questions, Mid-Level
- [Terraform Basics](https://sharpskill.dev/en/technologies/devops/interview-questions/terraform-basics.md): 22 questions, Mid-Level
- [Terraform Advanced](https://sharpskill.dev/en/technologies/devops/interview-questions/terraform-advanced.md): 22 questions, Mid-Level
- [Ansible & Configuration Management](https://sharpskill.dev/en/technologies/devops/interview-questions/ansible-configuration.md): 20 questions, Mid-Level
- [AWS Essentials](https://sharpskill.dev/en/technologies/devops/interview-questions/aws-essentials.md): 26 questions, Mid-Level
- [Azure Fundamentals](https://sharpskill.dev/en/technologies/devops/interview-questions/azure-fundamentals.md): 22 questions, Mid-Level
- [GCP Fundamentals](https://sharpskill.dev/en/technologies/devops/interview-questions/gcp-fundamentals.md): 22 questions, Mid-Level
- [Monitoring & Prometheus](https://sharpskill.dev/en/technologies/devops/interview-questions/monitoring-prometheus.md): 22 questions, Mid-Level
- [Logging & ELK Stack](https://sharpskill.dev/en/technologies/devops/interview-questions/logging-elk.md): 20 questions, Mid-Level
- [Alerting & Incident Response](https://sharpskill.dev/en/technologies/devops/interview-questions/alerting-incident-response.md): 20 questions, Mid-Level
- [Cloud Identity & Secrets](https://sharpskill.dev/en/technologies/devops/interview-questions/cloud-identity-secrets.md): 22 questions, Mid-Level
- [CI/CD Pipeline Security](https://sharpskill.dev/en/technologies/devops/interview-questions/cicd-pipeline-security.md): 20 questions, Mid-Level
- [Helm & Kubernetes](https://sharpskill.dev/en/technologies/devops/interview-questions/helm-kubernetes.md): 20 questions, Mid-Level
- [Runtime & Cluster Security](https://sharpskill.dev/en/technologies/devops/interview-questions/runtime-cluster-security.md): 24 questions, Senior
- [Container Supply Chain Security](https://sharpskill.dev/en/technologies/devops/interview-questions/container-supply-chain.md): 22 questions, Senior
- [Service Mesh & Istio](https://sharpskill.dev/en/technologies/devops/interview-questions/service-mesh-istio.md): 24 questions, Senior
- [GitOps & ArgoCD](https://sharpskill.dev/en/technologies/devops/interview-questions/gitops-argocd.md): 22 questions, Senior
- [Progressive Delivery](https://sharpskill.dev/en/technologies/devops/interview-questions/progressive-delivery.md): 20 questions, Senior
- [Distributed Observability](https://sharpskill.dev/en/technologies/devops/interview-questions/observability-distributed.md): 22 questions, Senior
- [Disaster Recovery & Backup](https://sharpskill.dev/en/technologies/devops/interview-questions/disaster-recovery.md): 20 questions, Senior
- [Performance Optimization](https://sharpskill.dev/en/technologies/devops/interview-questions/performance-optimization.md): 22 questions, Senior
- [SRE Principles](https://sharpskill.dev/en/technologies/devops/interview-questions/sre-principles.md): 24 questions, Senior
- [Chaos Engineering](https://sharpskill.dev/en/technologies/devops/interview-questions/chaos-engineering.md): 20 questions, Senior
- [Platform Engineering](https://sharpskill.dev/en/technologies/devops/interview-questions/platform-engineering.md): 22 questions, Senior

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