System Design · Senior · Question 20 of 75
What problems arise when running a service in multiple regions (active-active)?
- ✓Correct answer: Write conflicts, replication lag, data laws
- 2None - data syncs instantly and for free
- 3Only a bigger hosting bill; the architecture doesn't change
Explanation
Writing in two regions simultaneously requires a conflict resolution strategy (last-write-wins, CRDT, a user's "home region"). In addition, data localization laws (e.g. GDPR) restrict where personal data may be stored.