High availability (HA) and disaster recovery (DR) are distinct strategies that address different failure scopes in MySQL and MariaDB deployments. HA handles routine, localized failures within a single environment, optimizing for fast automated recovery measured in seconds (RTO-driven). DR assumes the entire primary site is lost, prioritizing data durability over speed (RPO-driven), with recovery measured in minutes to hours. Distance is the key physical separator: low-latency local environments enable tight coordination for HA, while cross-region replication introduces latency that makes synchronous replication impractical for DR. Synchronous replication suits local HA but degrades with distance and can propagate corruption rapidly. Asynchronous replication is more flexible, supporting both local HA and remote DR when paired with strong failover controls, promotion rules, and intelligent proxy routing. The practical differentiator is not replication mode but whether failover is controlled and predictable. A layered architecture combining fast local HA with distance-tolerant DR and clear operational rules is the recommended approach for business-critical systems.
Table of contents
Why High Availability and Disaster Recovery Are Still ConfusedHigh Availability Handles Failures Inside an EnvironmentDisaster Recovery Assumes the Environment Is LostWhy Does Distance Separate HA from DR?How Does Replication Strategy Differ Between HA and DR?When HA and DR Overlap in Real SystemsWhat Does a Strong MySQL and MariaDB HA and DR Architecture Look Like?Questions this post answers
What is the difference between high availability and disaster recovery for MySQL?
High availability protects against localized failures within a single environment (a crashed process, unreachable host) and targets fast automated recovery measured in seconds — it is RTO-driven. Disaster recovery assumes the entire primary site is gone and prioritizes data durability over speed — it is RPO-driven, with recovery measured in minutes to hours and some data loss often accepted as a deliberate trade-off. Teams designing MySQL resilience strategies track architecture patterns like these on daily.dev.
Should I use synchronous or asynchronous replication for MySQL disaster recovery?
Asynchronous replication is almost always the only stable option for MySQL disaster recovery across regions. Synchronous replication degrades rapidly as distance and latency grow, and can stall writes during brief network disruptions. Asynchronous replication keeps writes fast and predictable across any distance; with strong failover controls and promotion rules, the practical data loss window can be operationally indistinguishable from zero. Developers weighing replication trade-offs for cross-region MySQL setups find relevant comparisons on daily.dev.
Can asynchronous replication support local high availability in MySQL, not just disaster recovery?
Yes. Asynchronous replication can support local HA as well as remote DR when paired with appropriate failover controls and promotion rules. It avoids the write latency sensitivity and failure amplification risks of synchronous clusters, where an application bug or corruption can propagate across all nodes at high speed. The key differentiator is whether failover is controlled and promotion decisions are strictly constrained, not the replication mode itself. MySQL engineers evaluating HA architecture options keep up with evolving best practices on daily.dev.