Google Professional Cloud Network Engineer Question 576
Single answerGoogle Cloud PlatformYour organization is using a Google Cloud project with a Cloud NAT gateway to allow Compute Engine instances in a private subnet to access the internet. The team has identified a need to control the specific IP addresses that are used for NAT IP address allocation to simplify firewall rules in partner networks. Which configuration should you use to achieve this?
- A
Use automatic NAT IP allocation to allow Cloud NAT to dynamically assign ephemeral IP addresses.
- B
Use manual NAT IP allocation to reserve and assign specific external static IP addresses to the Cloud NAT gateway.
- C
Use automatic NAT IP allocation with a regional external IP address pool for more control.
- D
Use a private IP address range for NAT IP allocation.
Show answer and explanation
Correct answer: B
Explanation
To control the specific IP addresses used for NAT IP allocation, you must use manual NAT IP allocation. This allows you to reserve static external IP addresses and assign them to the Cloud NAT gateway, ensuring predictable IPs that can be used in firewall rules. Automatic allocation does not provide such control, and private IPs or regional IP pools are not applicable in this context.
- A. Incorrect.
Automatic NAT IP allocation dynamically assigns ephemeral IPs from Google’s pool and does not allow control over specific IP addresses. This does not meet the requirement to simplify firewall rules.
- B. Correct.
Manual NAT IP allocation allows you to reserve specific external static IP addresses and assign them to your Cloud NAT gateway, meeting the requirement to control IPs and simplify firewall rules.
- C. Incorrect.
Regional external IP address pools are not an option for Cloud NAT configuration. Cloud NAT only supports automatic or manual allocation of IPs.
- D. Incorrect.
Private IP address ranges cannot be used for NAT IP allocation, as NAT requires public IPs to facilitate communication with the internet.