Explanation
Remote VCN peering is the process of connecting two VCNs in different regions (but the same tenancy ). The peering allows the VCNs' resources to communicate using private IP addresses without routing the traffic over the internet or through your on-premises network. Without peering, a given VCN would need an internet gateway and public IP addresses for the instances that need to communicate with another VCN in a different region.
At a high level, the Networking service components required for a remote peering include:
- Two VCNs with non-overlapping CIDRs, in different regions that support remote peering. The VCNs must be in the same tenancy.
- A dynamic routing gateway (DRG) attached to each VCN in the peering relationship. Your VCN already has a DRG if you're using an IPSec VPN or an Oracle Cloud Infrastructure FastConnect private virtual circuit.
A remote peering connection (RPC) on each DRG in the peering relationship.
A connection between those two RPCs.
Supporting route rules to enable traffic to flow over the connection, and only to and from select subnets in the respective VCNs (if desired).
Supporting security rules to control the types of traffic allowed to and from the instances in the subnets that need to communicate with the other VCN.