Executive Summary

HiWiPay, a leading cross-border payments platform, faced a critical challenge: its entire production database was hosted on a single cloud provider (AWS), posing a significant compliance and operational risk.

To solve this, a specialized cross-cloud Disaster Recovery (DR) architecture was designed and implemented, establishing a resilient PostgreSQL environment spanning AWS EC2 and a GCP VM. By utilizing native PostgreSQL Streaming Replication, HiWiPay achieved an independent, secure, and cost-effective failover solution.

Key Outcomes

• 100% Regulatory Compliance - Achieved through geographically independent backup systems.

• Near-Zero Downtime & Data Loss - Validated during testing, ensuring business continuity.

• Sub-Second Replication Latency - Observed replication latency of < 1 second under normal load.

• Bidirectional Failover Capability - GCP replica can be promoted to primary, and AWS can revert to standby.

• Improved RTO/RPO Significantly faster recovery time compared to the legacy single-cloud setup.

The Business Challenge: Single-Point-of-Failure Risk

As a highly regulated fintech organization managing high-value financial transactions, HiWiPay operates under stringent compliance and uptime requirements. An internal audit highlighted a critical vulnerability: the production PostgreSQL database was solely hosted on AWS EC2.

This single-cloud dependency resulted in:

1. Compliance Violation: Non-compliance with audit standards requiring geographically independent and isolated backup environments.

2. Operational Risk: Exposure to potential service outages or region failures in the primary cloud.

3. Limited Recovery Options: Lack of an immediate, independent environment for rapid business continuity.

The objective was to implement a secure, compliant, and automated DR solution that guaranteed near-zero data loss and rapid recovery time, all without relying on expensive managed services like AWS RDS or GCP Cloud SQL.

In fintech, reliability equals trust. We needed a continuity plan that would guarantee zero data loss and no downtime even during unforeseen events.

- HiWiPay Executive

The Solution: Native Cross-Cloud Streaming Replication

To create a resilient, independent, and cost-effective solution, the Enhub team designed a custom Cross-Cloud Streaming Replication Setup leveraging native PostgreSQL features.

Here is the Architecture Overview

Implementation Steps

The solution was built on the stability and reliability of PostgreSQL's native replication features (Write-Ahead Log, or WAL, streaming):

• Primary Configuration: The AWS EC2 PostgreSQL instance was configured as the primary node, enabling streaming replication by setting appropriate parameters in postgresql.conf (e.g., wal_level = replica, max_wal_senders).

• Replication Role & Access: A dedicated, secure replication role was created in PostgreSQL to stream WAL data. Network security groups (pg_hba.conf and AWS/GCP firewalls) were strictly configured to permit secure communication between the two instances only.

• Replica Initialization: The GCP VM replica was initialized using pg_basebackup to create a foundational copy of the primary database.

• Real-Time Synchronization: Continuous WAL streaming was established, ensuring the standby GCP VM remained synchronized with the AWS primary in near real-time.

This technical method established a low-latency, asynchronous channel, making the entire solution highly performant and cost-effective compared to third-party tooling or managed services.

Business Outcomes and Impact

The implementation of the multi-cloud DR solution delivered measurable improvements across all areas, cementing HiWiPay's position as a more resilient and trusted fintech provider.

1. Continuity and Reliability

• Real-time Data Synchronization: Replication latency remained consistently < 1 second, validating the system’s ability to minimize data loss (low RPO).

• Validated Failover: Disaster recovery testing confirmed that the GCP VM could be promoted to primary successfully. Crucially, the system supports bidirectional failover, meaning the original AWS instance could be reverted to a standby role for ongoing protection.

• Uninterrupted Service: Intelligent load balancing and centralized traffic management were deployed to automatically route user traffic to healthy systems, ensuring zero downtime during validation.

2. Compliance and Risk Management

• Audit Compliance: Achieved full compliance with stringent financial audit and regulatory requirements by establishing a fully isolated and geographically independent backup environment.

• Security & Encryption: Data replication and all customer-facing applications were secured through end-to-end encryption, utilizing a Google-managed SSL certificate framework to meet financial data protection standards.

3. Operational Efficiency

• Cost Optimization: The custom, non-managed solution provided an independent backup environment using a pay-as-you-go model, resulting in a highly efficient cost structure.

• Faster Recovery: Achieved 95% faster recovery time (RTO) compared to previous recovery options.

  
  

  

Conclusion

This cross-cloud DR setup provided HiWiPay with a robust, cost-effective, and resilient foundation. It eliminated the single-cloud dependency, guaranteed business continuity, and ensured data integrity, providing essential operational confidence required in the highly regulated fintech industry.