1) If your workload requires consistently high throughput (MB/s) rather than high IOPS, which volume type is better?
The better EBS volume type is Throughput Optimized HDD(st1).
2) Which volume type should be used if multiple EC2 instances need shared access to the same data?
If multiple EC2 instances need shared access to the same data, you should use Provisioned IOPS SSD with EBS Multi-Attach, which allows a single volume to be attached to up to 16 instances in the same Az
3) What volume type would be best for hosting a NoSQL database like MongoDB or Cassandra?
The best EBS volume type is Provisioned IOPS SSD because it delivers high IOPS, low latency, and consistent performance needed for database workloads.
4) Can you use st1 or sc1 volumes for your root (boot) volume? Why or why not?
No, you cannot use st1 or sc1 volumes for root (boot) volumes because, they are HDD-based and optimized only for throughput, not low-latency random access.
Boot volumes require fast, consistent, low-latency SSD storage to load the operating system reliably.
5) When should you use the gp3 volume instead of gp2?
1. Lower cost
2.Better performance control for workloads with moderate to high I/O needs.