LESSON 05 / 5·2 min readIntermediate

How do DNS, load balancers, IAM and secrets fit together?

01 Understand02 Recall03 Prepare

Understand the concept

DNS resolves names to records, load balancers select healthy destinations, IAM controls identities and permissions, and secret managers store sensitive credentials. These components connect an application to users and dependencies without putting all configuration into code. A failure at any layer can look like “the API is down” from the outside.

Important ideas

  • DNS maps names to records; a load balancer routes traffic to healthy instances.

  • IAM controls who may access resources; service identities should have minimal access.

  • A secret manager stores sensitive credentials; apps retrieve only what they need.

  • Trace name resolution, connectivity, authentication and application response as separate stages during troubleshooting.

PAUSE & RECALL

Can you explain it without the notes?

How do DNS, load balancers, IAM and secrets fit together?

Use your own words. Explain an example and one limitation before checking the explanation.

Check your explanation

DNS resolves names to records, load balancers select healthy destinations, IAM controls identities and permissions, and secret managers store sensitive credentials. These components connect an application to users and dependencies without putting all configuration into code. A failure at any layer can look like “the API is down” from the outside.

CONNECT IT TO YOUR INTERVIEW

Turn this concept into a clear answer.

  • Network access and permission are different: a reachable database may deny credentials, while valid credentials do not fix a blocked route.
Practice this concept
YOUR NEXT STEP

You’ve reached the end of this guide.

Prepare for Delivery & cloud interviews

Adapted from 09_TESTING_GIT_DOCKER_CLOUD.md · “How do DNS, load balancers, IAM and secrets fit together?”. Examples are study fragments; framework behavior can depend on your version.