Database Replication Simulator — Interactive System Design Lab
Observe how a primary database replicates writes to replicas, experience replication lag under write pressure, and trigger a failover to see how replicas promote to leader. Essential for understanding read replicas and high availability.
Watch leader-follower replication lag and failover happen live.
This free interactive simulation runs directly in your browser — no account needed. Adjust the parameters and watch how the system responds in real time.
Concepts covered
- database replication
- leader follower
- replication lag
- failover
- high availability
- read replica
Read the guide
- Databases: SQL vs NoSQL — The heart of your architecture. Choosing the wrong database is the most expensive mistake you can make. Learn the 5 families of databases and when to use them.
- Consistency & Availability — The eternal trade-off. Learn why you can't have it all (CAP), how to handle the 99% of time when things ARE working (PACELC), and how to tune your truth.
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