What is Data Replication and how does it help?

Updated Apr 28, 2026

Short answer

Storing data on multiple nodes to ensure it remains available if one node fails.

Deep explanation

Intermediate reliability engineering involves handling distributed failures and defining metrics. Storing data on multiple nodes to ensure it remains available if one node fails.

Real-world example

A mobile app retrying to connect to a server when the signal is weak.

Common mistakes

  • Retrying indefinitely without a cap, which can crash the server when it comes back up.

Follow-up questions

  • What are the three states of a Circuit Breaker?

More Availability & Reliability interview questions

View all →