Centralized Routing: By configuring each VCN,s route table to point to the DRG, you establish a centralized routing hub, eliminating the need for complex, individual connections and simplifying network management.
Efficient Traffic Flow: Traffic from any VCN can reach the on-premises network through the DRG, facilitating optimal routing and avoiding unnecessary hops.
Scalability: This approach easily scales as you add more VCNs in different regions, as only the VCN route table updates are needed.
Comparison with other options:
Separate DRGs per Region (A): This creates unnecessary complexity and management overhead compared to using a single DRG.
IPSec Tunnels per VCN-DRG (C): While secure, it offers no centralized management advantage and requires multiple configurations, especially for many VCNs.
Open DRG Security List (D): This compromises security by exposing all VCNs to traffic from anywhere, violating the principle of least privilege.