Access a VPC-hosted Amazon OpenSearch Service domain with SAML authentication using AWS Client VPN

This article provides a comprehensive guide for securely accessing VPC-hosted Amazon OpenSearch Service domains using SAML authentication via AWS Client VPN and IAM Identity Center.

• Combines Client VPN, Transit Gateway, and IAM Identity Center for enterprise-grade access
• OpenSearch Service supports multiple authentication methods including SAML federation
• SAML with IAM Identity Center supports identity provider-initiated authentication only
• Transit Gateway acts as central hub for VPC connectivity and network management
• Client VPN eliminates need for bastion hosts while providing secure remote access
• Step-by-step setup includes VPC creation, Transit Gateway configuration, and SAML integration
• Security group referencing enables least privilege access between VPCs
• End-to-end testing validates Client VPN and OpenSearch Service authentication flow

This solution provides a scalable, secure architecture for enterprise users to access private OpenSearch Service domains without bastion hosts, using centralized identity management through IAM Identity Center.