The JusDB Database Engineering Blog

Understand RDS Multi-AZ for HA and Read Replicas for read scaling — failover behavior, replication lag, and costs

Configure Redis Cluster for horizontal scaling — hash slots, replication, failover, and client-side routing

Set up MySQL Orchestrator for automatic failover, topology discovery, and master election at scale

PostgreSQL WAL retention is a balancing act — too little and standbys fall behind; too much and you risk disk exhaustion. Here's how to configure wal_keep_size and manage replication slots safely.

Deploy Aurora Global Database for sub-second cross-region replication. Understand storage-level replication, planned failover vs unplanned, and write forwarding for read regions.

Build selective, cross-version PostgreSQL replication with logical replication. Learn publications, subscriptions, conflict handling, and real-world use cases.

MySQL 8.4 GTID replication eliminates binlog position tracking and makes failover deterministic. Learn to configure GTID mode, initialize replicas correctly, and use Orchestrator for automated failover.

Migrate MySQL schema changes online with gh-ost using binlog streaming instead of triggers. Covers dynamic throttling via Unix socket, postpone-cut-over flag, and test-on-replica mode.

MySQL replication errors 1062 and 1032 stop your replica SQL thread silently. Learn to diagnose binlog failures, fix data drift with pt-table-sync, and configure GTID-safe replication.

MySQL InnoDB Cluster combines Group Replication, MySQL Shell, and MySQL Router into a complete HA solution. Here's how to deploy and manage it in production.

Logical replication in PostgreSQL has a critical gap: slots do not survive failover. PostgreSQL 17 finally fixes this with failover slots, plus adds row and column filtering for selective replication.

MySQL Group Replication and Galera Cluster both promise multi-primary high availability, but they behave very differently under load, network partitions, and node failures.