The key requirements are: OpenSearch Service must be deployed within a VPC (VPC-only access), and developers must access OpenSearch from their local machines across multiple locations, including home networks. The most suitable low-overhead approach is to provide remote users with secure client-based connectivity into the VPC so they can reach private endpoints.
AWS Client VPN is a managed client-based VPN service that allows individual users to establish secure TLS VPN connections from their devices into a VPC. By associating a Client VPN endpoint with a subnet in the VPC and configuring authorization rules and routes, developers can access private resources (including VPC-only Amazon OpenSearch Service endpoints) as if they were on the corporate network. Client VPN is designed for distributed workforces and supports users connecting from anywhere without requiring each remote location to have dedicated network appliances.
Option A matches the need for remote developer access from home and multiple offices with the least operational overhead because it is a managed service for user-based VPN access and does not require running and maintaining bastion fleets or building site-to-site networks for each location.
Option B is not correct because AWS Site-to-Site VPN is designed to connect networks (for example, an office network or data center) to AWS, not to provide individual developers remote access from arbitrary home networks. Also, instructing developers to use an OpenVPN client does not align with how Site-to-Site VPN is typically used; Site-to-Site VPN terminates on a customer gateway device, not on individual laptops.
Option C is not correct because Direct Connect is designed for dedicated private connectivity between on-premises networks and AWS. It is not a solution for individual developers connecting from home. Additionally, using a public VIF is for reaching public AWS endpoints, whereas the requirement is to keep access within a VPC. A public VIF does not provide private VPC access to VPC-only service endpoints.
Option D is not the best choice because a bastion host provides SSH access to instances, not direct, secure network-level access to VPC-only managed service endpoints from developer tools. It also increases operational overhead (patching, hardening, monitoring, scaling) and introduces additional security considerations. Developers also typically need browser-based or tool-based access to OpenSearch Dashboards, which is better served by VPN access into the VPC than SSH tunneling through a bastion host as a primary access mechanism.
Therefore, configuring AWS Client VPN to provide developers with secure connectivity into the VPC is the correct solution.
[References:AWS documentation on AWS Client VPN as a managed client-based VPN service for remote user access to VPC resources.AWS documentation on VPC-only access patterns for managed services and using VPN connectivity to reach private endpoints from remote networks., , ]
