Cloud and Platform Fundamentals for DevOps
What to know
Candidates should understand core cloud service models-IaaS, PaaS, SaaS, FaaS-and the shared responsibility model: the provider secures the cloud, the customer secures what runs in it. Know regions and availability zones for fault isolation, elasticity and autoscaling, managed vs. self-managed services, and cost drivers (egress, idle capacity, storage tiers). Understand identity and access management (least privilege, roles over long-lived keys), virtual networks, subnets, and security groups, and infrastructure as code as the bridge to cloud. Platform engineering concepts include internal developer platforms, golden paths, and self-service with guardrails.
Traps
A frequent distractor places customer data security entirely on the provider-wrong under shared responsibility. Another confuses availability zones (isolated datacenters within a region) with regions (geographic separation). Watch for answers that create long-lived access keys instead of role-based credentials. Also, autoscaling does not fix a slow application; it scales capacity, not efficiency.
Rule of thumb
Design for failure of any single zone, and prefer managed services unless you have a specific reason not to. Tag resources for cost attribution and apply least-privilege roles.
Worked example
A workload must survive a datacenter outage. Deploy across at least two availability zones behind a load balancer with health checks, and use a replicated managed database. A single-AZ deployment with backups is not high availability-backups address durability and recovery time, not continuous uptime.