Database Connectivity and Transaction Resilience

Q: How does digiRunner handle database connection failures? Will transactions be interrupted?

A: digiRunner incorporates built-in resilience mechanisms to handle database connectivity disruptions. The impact depends on the duration of the outage and your deployment architecture.

1. Short-Term Instability (Network Jitter)

• Impact: Minimal or none.

• Mechanism: digiRunner uses in-memory caching to maintain service continuity. During brief network disruptions, API services can continue serving read requests using cached data.

• Transaction Behavior: Write operations that require database commits may fail if the database is temporarily unreachable. Short disruptions typically do not affect transactions that have already been committed.

• Limitation: If cached data expires while the database remains unavailable, the system cannot refresh the data, which may eventually affect service availability.

2. Long-Term Database Outage

• Impact (Single-node deployment): Once cached data expires, API services that require database access—particularly write operations—will fail. In-flight transactions that cannot complete database commits will be rolled back.

• High-Availability Option: For mission-critical environments requiring continuous service during extended database outages, digiRunner provides a Dual-Centered In-Memory Gateway Architecture (Enterprise Edition). This architecture removes single points of failure and allows the gateway to continue serving APIs using in-memory data even if the primary database becomes unavailable.

This architecture is intended for high-availability deployments and requires Enterprise Edition licensing and professional configuration.

3. Database in Read-Only Mode

• API Services: Read-only API operations may continue functioning, particularly if the required data is already cached.

• Write Operations: APIs that attempt to perform insert, update, or delete operations will fail because database write access is required to complete the transaction.

• Admin Console (AC): Administrative functions may be unavailable. The Admin Console requires write access for operations such as audit logging, user management, API registration, and system configuration updates.

Keywords: Database Failover, HA, High Availability, In-Memory Caching, Read-Only Mode, Resilience