Cianplan

Level 4: Reliability, security & cloud · L4.6 AWS architecture decisions (SAA-C03)

Migrating legacy applications: the 7 Rs and rehosting with MGN

Pick a migration strategy (retire, retain, rehost, relocate, repurchase, replatform, refactor) from a scenario's constraints, rehost servers with AWS Application Migration Service, and make a legacy app more reliable without changing its code.

13 min · Pro

What you take away

  • The 7 Rs are retire, retain, rehost, relocate, repurchase, replatform and refactor; AWS advises rehosting, replatforming or relocating first and modernizing after, because refactoring is the most complex and costly.

And 3 more inside the class, in Pro.

How the class is laid out

  1. The problem
  2. The simple version
  3. The 7 Rs, and the signal for each
  4. Rehosting with MGN
  5. The tools that closed, and what the exam still means
  6. Reliable without touching the code
  7. Check your understanding