Basic information
| Field | Details |
|---|---|
| English / full name | VPC Peering |
| Chinese | VPC 对等连接 |
| Japanese | VPC ピアリング |
| Review priority | 考试频率 ⭐⭐⭐⭐⭐ |
| Often confused with | Transit Gateway / PrivateLink |
In one sentence
A direct, non-transitive private connection between two VPCs with non-overlapping CIDRs.
Core summary
After acceptance, both sides still need routes to the peer CIDR plus security group and NACL permissions.
Study points
- Works across accounts and Regions.
- A–B and B–C do not create A–C reachability.
- A peer cannot borrow the other VPC’s IGW, NAT, VPN, Direct Connect, or gateway endpoint.
- Use Transit Gateway when a large peering mesh becomes hard to govern.
Common pitfalls
- Accepted does not mean reachable; routing must work in both directions.
- For overlapping CIDRs with service-only access, consider PrivateLink.
Key memory
Two VPCs, non-overlapping addresses, bidirectional routes, and no transitive routing.