Soru

Zorluk: ZorHybrid and Multi-Account Network Connectivity Design

A multinational enterprise is designing a hybrid network connectivity architecture to connect its on-premises data center (IP range 192.168.0.0/16192.168.0.0/16) to its AWS multi-account environment. The AWS environment consists of dozens of VPCs distributed across useast1us-east-1 and uswest2us-west-2. The company requires a highly available network design that satisfies the following conditions:

* Primary connectivity must use a 10 Gbps10\text{ Gbps} AWS Direct Connect connection terminated at a location associated with useast1us-east-1.
* Backup connectivity must use AWS Site-to-Site VPN connections over the public internet.
* All outbound traffic from both AWS regions to the on-premises data center must prefer the Direct Connect connection under normal conditions, and automatically fail over to the local region's VPN connection if the Direct Connect path becomes unavailable.
* Inbound traffic from the on-premises data center to AWS must prefer the Direct Connect path under normal conditions.
* Administrative overhead and manual route table updates must be minimized.

Which configuration should a solutions architect recommend to meet these requirements?

  1. Establish an AWS Transit Gateway (TGW) in each region and attach the local spoke VPCs. Connect the Direct Connect connection to a Direct Connect Gateway (DXGW) using a Transit Virtual Interface (Transit VIF), and associate the DXGW with the TGW in both regions. Establish BGP-enabled Site-to-Site VPN connections directly to each TGW. Configure the customer gateway to advertise 192.168.0.0/16192.168.0.0/16 over both the Direct Connect and VPN connections. In the TGW route tables, enable route propagation for both the DXGW and VPN attachments. On the customer gateway, configure BGP local preference to prefer routes received over the Direct Connect connection.Cevap
  2. B
    Establish an AWS Transit Gateway (TGW) in each region and attach the local spoke VPCs. Connect the Direct Connect connection to a Direct Connect Gateway (DXGW) using a Transit Virtual Interface (Transit VIF), and associate the DXGW with the TGW in both regions. Establish BGP-enabled Site-to-Site VPN connections directly to each TGW. Configure static routes for 192.168.0.0/16192.168.0.0/16 in the TGW route tables pointing to the DXGW attachment, and duplicate static routes with a higher metric pointing to the VPN attachments to enable automatic failover.
  3. C
    Deploy Virtual Private Gateways (VGWs) in all spoke VPCs in both regions and attach them directly to a Direct Connect Gateway (DXGW) via Private Virtual Interfaces (Private VIFs) for primary connectivity. Establish a software-defined VPN mesh between the on-premises customer gateway and EC2 instances running software routers in each VPC for backup. Use BGP on the customer gateway to route transitive traffic between the VPCs in different regions through the DXGW.
  4. D
    Establish an AWS Transit Gateway (TGW) in useast1us-east-1 and attach all spoke VPCs in both regions to it. Deploy a single NAT Gateway in a central egress VPC in useast1us-east-1 and establish the Direct Connect connection using a Public Virtual Interface (Public VIF). Set up a single Site-to-Site VPN connection from the customer gateway to the TGW in useast1us-east-1 as a backup. Configure the on-premises customer gateway to route all traffic to AWS through the NAT Gateway's public IP address.

Cevap

The correct configuration uses AWS Transit Gateways associated with a Direct Connect Gateway using a Transit VIF for the primary path, and BGP-enabled Site-to-Site VPNs directly connected to each Transit Gateway for backup. By propagating routes from both paths, Transit Gateway natively prefers the Direct Connect Gateway path due to its built-in route priority. To ensure symmetric routing, BGP Local Preference is configured on the customer gateway to prefer the Direct Connect path for traffic entering AWS.
The correct configuration uses AWS Transit Gateways associated with a Direct Connect Gateway using a Transit VIF for the primary path, and BGP-enabled Site-to-Site VPNs directly connected to each Transit Gateway for backup. By propagating routes from both paths, Transit Gateway natively prefers the Direct Connect Gateway path due to its built-in route priority. To ensure symmetric routing, BGP Local Preference is configured on the customer gateway to prefer the Direct Connect path for traffic entering AWS.

Adım Adım Çözüm

1
Connect the multi-region Transit Gateways (TGWEastTGW-East and TGWWestTGW-West) to a central Direct Connect Gateway (DXGW) using a Transit VIF to establish the primary hybrid path.
Spoke VPCs in both regions can route traffic to the on-premises data center via their local Transit Gateways and the shared DXGW.
Direct Connect Gateway enables multi-region connectivity to Transit Gateways over a single Transit VIF, minimizing routing complexity and cost.
2
Establish BGP-enabled AWS Site-to-Site VPN connections from the customer gateway directly to the TGW in each region to serve as the backup path.
Backup paths are available locally in each region, bypassing the Direct Connect path if it fails.
Terminating the VPN directly on the Transit Gateways allows BGP to dynamically propagate backup routes.
3
Advertise the on-premises summary CIDR (192.168.0.0/16192.168.0.0/16) from the customer gateway over both the Direct Connect and VPN BGP sessions, and enable route propagation in the TGW route tables.
TGW automatically prefers the DXGW-propagated route over the VPN-propagated route for outbound traffic.
The AWS Transit Gateway route selection algorithm natively prioritizes Direct Connect Gateway attachments over VPN attachments for identical prefixes.
4
Configure BGP Local Preference on the on-premises customer gateway to prefer routes received via the Direct Connect Transit VIF over the VPN tunnels.
Inbound traffic from the on-premises data center to AWS VPCs will prefer the Direct Connect path.
AWS BGP advertisements alone do not guarantee customer-side path preference; Local Preference is the standard BGP mechanism to control outbound routing decisions on the customer gateway.

Anahtar Kavram

AWS Transit Gateway path selection and BGP path tuning for hybrid and multi-region network failover.
Tahmini Süre:3m 0s
Bu soruyu puanla