What are AWS storage services?
Why Interviewers Ask This
This question tests conceptual clarity. Interviewers want to hear a precise, confident definition before moving to more complex AWS / Cloud Computing topics. It also reveals how well you can explain technical ideas to non-experts.
Answer
AWS offers several storage services for different use cases: Amazon S3 (Object Storage): flat key-value store for any type of file. Unlimited capacity, 11 nines durability. Best for: backups, media, data lakes, static websites, application artifacts. Amazon EBS (Elastic Block Store): network-attached block storage for EC2 instances. Like a hard drive — can be formatted with a filesystem. Persists independently of EC2 lifetime (detach and re-attach). Types: gp3 (General Purpose SSD — default, balanced), io2 Block Express (high IOPS for databases), st1 (Throughput Optimized HDD for big data), sc1 (Cold HDD — cheapest, infrequent access). Multi-Attach for io1/io2 (limited use). Snapshots to S3 for backup/migration. One EBS to one EC2 instance (same AZ). Amazon EFS (Elastic File System): fully managed NFS (Network File System). Multiple EC2 instances can mount simultaneously — shared filesystem. Auto-scales from GB to PB. Multi-AZ (Regional) or One Zone. Performance modes: General Purpose (latency-sensitive), Max I/O (highly parallel). Throughput modes: Bursting, Provisioned, Elastic (auto-scale). Much more expensive than EBS per GB. Use for: content management, home directories, dev environments, shared data. Amazon FSx: managed third-party filesystems: FSx for Windows File Server (SMB, Active Directory), FSx for Lustre (high-performance computing, ML training), FSx for NetApp ONTAP, FSx for OpenZFS. AWS Storage Gateway: hybrid storage — connects on-premises to AWS storage.
Pro Tip
If you're unsure about a detail, say so honestly and explain your reasoning. Interviewers respect candidates who can think through uncertainty rather than bluffing.