Accessing your DB Cluster from an Amazon EC2 instance in another VPC - Amazon Neptune
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Accessing your DB Cluster from an Amazon EC2 instance in another VPC

An Amazon Neptune DB cluster can only be created in an Amazon Virtual Private Cloud (Amazon VPC), and its endpoints are only accessible within that VPC, usually from an Amazon Elastic Compute Cloud (Amazon EC2) instance running in that VPC.

When your DB cluster is in a different VPC from the EC2 instance you are using to access it, you can use VPC peering to make the connection:

      Diagram of accessing a Neptune cluster from a different VPC.

A VPC peering connection is a networking connection between two VPCs that routes traffic between them privately, so that instances in either VPC can communicate as if they are within the same network. You can create a VPC peering connection between VPCs in your account, between a VPC in your Amazon account and a VPC in another Amazon account, or with a VPC in a different Amazon Region.

Amazon uses the existing infrastructure of a VPC to create a VPC peering connection. It is neither a gateway nor an Amazon Site-to-Site VPN connection, and it does not rely on a separate piece of physical hardware. It has no single point of failure for communication and no bandwidth bottleneck.

See the Amazon VPC Peering Guide for more information about how use VPC peering.