Google Professional Cloud Network Engineer Question 81
Select 3Google Cloud PlatformYour company has acquired a public advertised prefix (PAP) and public delegated prefix (PDP) from your regional internet registry. You want to configure a Google Cloud environment where you can use a Private NAT gateway to allow private instances in your VPC to access external services using non-RFC 1918 IP addresses from your PDP while ensuring the advertised PAP remains visible to external networks. What steps should you take to achieve this configuration?
- A
Create a Private NAT gateway and configure it to use IP addresses from the public delegated prefix (PDP).
- B
Ensure the public advertised prefix (PAP) is advertised from your Google Cloud environment using Cloud Router.
- C
Reserve static external IP addresses from the public advertised prefix (PAP) and assign them directly to the private instances.
- D
Configure a route to forward all egress traffic to the Private NAT gateway.
- E
Enable bidirectional routing between the PDP and the PAP using a custom route.
Show answer and explanation
Correct answers: A, B, D
Explanation
To enable private instances in a VPC to access external services using public IPs from a delegated prefix (PDP), you must configure a Private NAT gateway to use the PDP. Additionally, the public advertised prefix (PAP) must be advertised using Cloud Router so that external networks recognize the IPs. Finally, egress traffic from the private instances must be routed through the NAT gateway. These steps ensure proper communication while maintaining the visibility of the PAP to external networks.
- A. Correct.
Correct. A Private NAT gateway can be configured to use addresses from the public delegated prefix (PDP), allowing private instances in the VPC to use these public IPs for external communication.
- B. Correct.
Correct. To ensure the public advertised prefix (PAP) is visible to external networks, you need to advertise it using a Cloud Router.
- C. Incorrect.
Incorrect. Static external IPs from the PAP cannot be directly assigned to private instances. Instead, NAT should be used for private-to-public IP translation.
- D. Correct.
Correct. You need a route to forward the egress traffic from the private instances to the Private NAT gateway so that the traffic uses the desired public IPs.
- E. Incorrect.
Incorrect. Bidirectional routing between PDP and PAP is not a valid configuration. NAT handles the translation between private and public IPs.