EO Engineering Learning OS
PROJECT LADDER · P13
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CORE PROJECT · TARGET L3–4 · 7 days
P13

Amazon ECS

Operate containerized services through managed scheduling, identity, networking and deployment controls.

01 / CONCEPT MAP

Know what the parts mean.

Learn each concept deeply enough to recognize it, place it in the system and reason about normal and failed behavior.

01

Cluster and service

Define it · locate it · observe it · explain its failure mode.

02

Task definition

Define it · locate it · observe it · explain its failure mode.

03

Task vs execution role

Define it · locate it · observe it · explain its failure mode.

04

Networking

Define it · locate it · observe it · explain its failure mode.

05

Load balancer

Define it · locate it · observe it · explain its failure mode.

06

Rolling deployment

Define it · locate it · observe it · explain its failure mode.

02 / SYSTEM FLOW

Trace it end to end.

Registry→task definition→ECS service→tasks→ALB→CloudWatch

For every transition: identify input, output, identity, protocol, state, trust boundary, evidence and owner.

03 / GUIDED BUILD

Build, observe and explain.

Documentation and AI are allowed. The engineer must review every output and demonstrate the result from direct evidence.

  1. 01Create task definition
  2. 02Separate roles
  3. 03Deploy private tasks
  4. 04Attach ALB
  5. 05Configure health and scaling
  6. 06Perform rolling update and rollback
04 / INCIDENT

Tasks repeatedly stop because execution-role and task-role responsibilities are confused.

Required investigation

State impact → collect evidence → form competing hypotheses → test the cheapest discriminator → isolate root cause → contain → correct → verify.

Evidence pack

Timeline, relevant logs/metrics, failed assumptions, root cause, correction, verification and one prevention action.

AI ownership

AI may suggest causes and commands. The engineer must explain why each check is safe, what result is expected and how the result changes the hypothesis.

05 / DESIGN CHALLENGE

Defend the decision.

Compare EC2, ECS on Fargate and ECS on EC2 for this workload.

06 / VERIFY, SUBMIT & REVIEW

Submission evidence

Architecture review

  • Explain amazon ecs without relying on memorized commands.
  • Draw the flow and name what crosses every arrow.
  • Identify the most likely, highest-impact and hardest-to-detect failure.
  • Show the evidence that proves the solution works.
  • Defend one security, reliability and cost trade-off.

Definition of Done

  • Acceptance criteria pass
  • Flow is drawn and explained
  • Security implications considered
  • Logs/metrics checked
  • Failure is tested
  • AI output is understood
  • Runbook is reusable
  • Mentor review passes
07 / MENTOR GUIDE

Do not score memory. Score the engineer’s ability to form a model, collect evidence, make a safe change and defend the trade-off.

1 Cannot explain2 Understands with gaps3 Implements and troubleshoots4 Designs and reviews