Description
A VPC peering connection is a networking connection between two VPCs that enables you to route traffic between them and access their resources.
 | Uses AWS backbone without traversing the internet |
 | Transitive peering is not supported |
Considerations
- Must update route tables to configure routing (pcx-)
- Cannot have overlapping CIDRs
- Limits are 50 VPC peers per VPC, up to 125 by request
- Must update the inbound and outbound rules for VPC security group to reference security groups in the peered VPC.
Cross account, Inter-region
- In same or in another AWS account.
- VPCs can be in different regions (inter-region). In that case, data sent between VPCs is encrypted.
Inter-region limitations
- You cannot create a SG rule that references a peer SG.
- Cannot enable DNS resolution.
- Maximum MTU (maximum transmission unit) is 1500 bytes (no jumbo frames support). https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/network_mtu.html
- Limited region support.
Example of a VPC peering connection
Using VPC peering to connect VPC Management to a “managed” VPC to benefit from a Shared Directory Service (Microsoft AD) and from Remote Desktop Gateway.
