Cross-Account Role Assumption

Cross-Account Role Assumption

This lesson deepens AWS Networking & Identity using the same subject areas emphasized by official documentation: AWS VPC, IAM and networking docs: VPCs, subnets, route tables, NAT, endpoints, ELB, Route 53 and federation. The goal is to turn Cross-Account Role Assumption into a production skill: you should know the concept, the configuration surface, the safety controls, the operational checks, and the rollback path.

Documentation Coverage

• Core terms and object model for this topic.
• Configuration options, defaults, and lifecycle behavior from the docs.
• Security, reliability, and ownership boundaries.
• Validation steps before and after the change.
• Common failure modes and diagnostic signals.

Production Implementation Flow

1. Define the source of truth: Git, configuration, API, state file, or control plane.
2. Design the safest repeatable workflow, including dry-run or plan output where possible.
3. Attach CI/CD, policy, security, and peer-review gates.
4. Observe metrics, logs, events, or traces after the change.
5. Document rollback, escalation owner, and evidence for the change record.

aws sts get-caller-identity
aws resourcegroupstaggingapi get-resources --tag-filters Key=Environment,Values=prod
aws cloudwatch describe-alarms --state-value ALARM

Mastery Standard

You understand Cross-Account Role Assumption when you can explain it, configure it, test it, monitor it, and recover it under incident pressure without relying on undocumented manual steps.