CEC Cloud Infrastructure

Lab VMs for the Cloud & Edge Computing course: 50 student VMs (t3a.small) and 20 group VMs (t3a.medium), all in one VPC. Each VM gets an Elastic IP (stable across stop/start), an SSH key pair, and an IAM console user that can start/stop/reboot only its own VM.

State lives in S3 (sue-aws-student-01-tfstate), never in git.

Prerequisites

An AWS profile named sue-aws-student-01 in ~/.aws/config with administrator credentials for the account, or pass your own profile with -var aws_profile=<their-profile>.

Deploy

terraform init
terraform plan
terraform apply
terraform output -json > outputs.json
python3 format.py   # -> student_credentials.json + group_credentials.json

The generated credential files are gitignored — never commit them.

Power-state lifecycle

VMs are created stopped (enforce_stopped = true) for the pre-course test phase. Once the environment is signed off, set enforce_stopped = false and apply once: terraform stops managing power state entirely, so starting/stopping VMs in the console is never reverted.

Decommissioning a drop-out

Add the VM key to decommissioned_vms (e.g. in a *.tfvars file):

decommissioned_vms = ["student-17"]

terraform plan must show destroys only for ["student-17"]-suffixed resources; then terraform apply. No other VM is touched.

Notes

• Extra ingress ports can be added to the lab-ssh-access security group via the console; applies won't revert them (rules are separate resources).
• The AMI (Ubuntu 24.04) is looked up at plan time but ignore_changes = [ami] prevents fleet replacement when Canonical publishes new images.