Amazon EC2

Virtual servers in the cloud.

EC2 rents virtual machines (instances) by the second. An instance is defined by its AMI (operating system image), instance type (e.g. t3.micro: 2 vCPU, 1 GiB RAM), key pair, network settings and storage.

What mattered in the labs

• Pick the Region first – resources and prices are per Region.
• Security groups decide which ports are reachable (22 for SSH, 23 for Telnet, 80/443 for web).
• Stopped instances stop compute charges but their EBS volumes are still billed.
• Always terminate lab instances and check that their volumes are gone.