- Learn AWS
- Architecture
- Pilot light disaster recovery
Architecture pattern
AWS Pilot light disaster recovery architecture
when a second region must exist, but not cost like one
Data is replicated continuously to a second region while the compute stays switched off, defined as templates. Recovery is bringing that stack up and repointing DNS — minutes, not days, at a fraction of running two production estates.
What it runs through
In the order a request or a record moves through it. Each one links to the page that explains it.
- RDSAmazon RDS
- S3Amazon S3
- CloudFormationAWS CloudFormation
- Route 53Amazon Route 53
Signals in a brief that point here
Phrases that, when you meet them in a scenario, mean this shape rather than another. They are the tell, and they are what an exam question is built around.
- “tolerate some minutes of data loss”
- “cheaper than a duplicate environment”
- “bring it up in another Region”
- “RPO”
- “RTO”
What it costs you
The recovery path only works if you actually rehearse it. Untested DR is a hope, not a plan.
Every shape has one. A design decision with no stated downside is usually a decision nobody has finished making.
Learn the services in it
- AWS RDS and AuroraManaged relational databases: six engines run for you, plus Aurora, AWS's own MySQL- and PostgreSQL-compatible engine, with standbys, replicas and backups built in.
- AWS S3Object storage for any amount of data: files kept as objects in buckets, designed for eleven nines of durability, and private until you grant access.
- AWS Route 53AWS's DNS service. It registers domains, answers queries for them with a choice of routing policies, and sends traffic away from endpoints that fail their health checks.
Shapes it is easily confused with
These run through some of the same services, which is exactly why a brief that fits one can look like it fits another.
Now build it from a brief
Reading a shape and producing one from a scenario that never names a service are different skills, and the exam asks for the second. The scenarios give you the brief; you draw the architecture and it is scored against what the brief requires.