Lecture Notes: Cloud Engineer Job Interview

Introduction

• Interview with Karen, a cloud engineer at a startup.
• Discussion of experience, skills, and real-world scenarios.

Professional Experience

• Works as a cloud engineer for a company that publishes digital surveys on various websites.
• Designs and deploys websites using Docker, Kubernetes, and CI/CD pipelines.
• Evaluates clients' budgets for cloud system architecture.

Key Concepts and Tools

Docker

• Docker File: Base layer in Docker, with additional functionalities added as layers.
• Challenges: Issues with encryption keys when pushing Docker images; resolved with compatible encryption keys.
• Security Knowledge: Limited; could not specify how to secure a Docker image.

AWS CloudFormation

• Role: Automated tool for deploying resources on AWS.
• Explanation: Described as platform-as-a-service (PaaS) but interviewer indicated that the explanation was incomplete.

Monitoring Tools

• Prometheus: Logs metrics like CPU utilization and network metrics for EC2 instances.
• Grafana: Used for creating dashboards and analytics based on logs.

Advanced Topics and Scenarios

Terraform

• State: Reflects current system's state vs. the desired configuration state (e.g., desired vs. actual number of instances).
• Change Management: Ensures that infrastructure matches the desired state as per configuration files.

Content Delivery Networks (CDN)

• AWS CloudFront: Used for global content delivery and caching to reduce latency. Mentioned latency issues when updating resources.

Security Aspects

• Implemented WAF (Web Application Firewall) and scaled using ALB (Application Load Balancer) and ASG (Auto Scaling Group).
• Used geofencing to block access from certain countries.
• Subnets & Security Groups:
  • Security Groups: Manage permissions for resource access.
  • Subnets: Used for IP management.

Cost Optimization

• Reduced costs by caching data in DynamoDB and using CDN to limit requests to databases.

Serverless Technologies

• AWS Lambda: Serverless computing. Example: JS script for counting website hits stored in DynamoDB.
• Use Cases: Suitable for functions running under 15 minutes.

Additional Topics Discussed

SLAs and Related Concepts

• SLA (Service Level Agreement): Agreement on service standards.
• Could not elaborate on SLI (Service Level Indicator) and SLO (Service Level Objective).

Kubernetes

• Basic understanding; still in the learning phase.

VPN (Virtual Private Network)

• Secure network requiring credentials for access.
• Establishing interconnectivity using gateways.
• Methods for on-premise to cloud connections.

GitHub and Distributed Systems

• Admitted limited knowledge about distributed systems.

Conclusion

• Karen displayed strong practical experience but had some gaps in advanced topics and theoretical aspects.

Note: Feedback from the interviewer was not included in the transcript.