AWS Interview DropAdvanced TierScenario+50 XP on read
How do you architect a highly available, zero-downtime database migration in AWS RDS?
#RDS#Migration#HA
Core Summary
Zero-downtime migration means never asking for a maintenance window. You replicate into the new database while the old one still serves traffic, verify continuously, then cut over at the connection layer in seconds — with a rehearsed path back.
Hints
Hint 1: DMS with CDC keeps the target in sync while the source serves traffic
Hint 2: The cutover happens at the DNS or proxy layer, not in the database
Hint 3: Plan the rollback before the cutover, not after
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