Google Updated Professional-Cloud-Security-Engineer Exam Questions and Answers by kaia

Firewall Rule Analysis: Analyze the existing VPC firewall rules to identify any rules that might allow traffic between VM instances based on the same service account.

Priority Check: Check the priority of these rules. A rule with a priority lower than 1000 (such as 999) will take precedence over your tag-based rules.

Service Account Configuration: Since your VM instances are deployed without any service account customization, they are likely using the default service account. A firewall rule allowing traffic between instances using this default service account will override the tag-based rules if it has a higher priority.

Testing and Validation: Disable or adjust the priority of the rule with priority 999 to test if the tag-based segmentation works correctly. Validate that the traffic is segmented according to your intended configuration. References:

Google Cloud - VPC Firewall Rules

Google Cloud - Service Accounts

Google Cloud Directory Sync (GCDS): Install and configure GCDS to synchronize your on-premises Active Directory with Google Cloud Identity. This tool helps in maintaining consistency between your local directory and Google Cloud.

IAM Groups: Create IAM groups in Google Cloud with permissions that correspond to your Active Directory groups. This mapping ensures that users inherit the appropriate permissions based on their AD group membership.

Synchronization: Set up regular synchronization schedules to keep the user and group information up-to-date between your on-premises AD and Google Cloud.

Access Management: Use these IAM groups to manage access to Google Cloud resources, ensuring that permissions are applied consistently and securely. This approach leverages existing AD infrastructure for identity management, providing a seamless integration with Google Cloud. References:

Google Cloud - Google Cloud Directory Sync

Google Cloud - IAM Groups

Rotating a user-managed Service Account key involves creating a new key, updating your application to use the new key, and then deleting the old key to maintain security. Here’s the step-by-step process:

Create a New Key: Use the Google Cloud Console or gcloud command-line tool to create a new key for the service account. This generates a new key pair and provides you with the private key.

gcloud iam service-accounts keys create new-key-file.json --iam-account=YOUR_SERVICE_ACCOUNT_EMAIL

Update Application: Update your application configuration to use the new key. This might involve replacing the old key file with the new one or updating the environment variables or configurations that point to the key file.

Delete the Old Key: Once you have confirmed that the application is working correctly with the new key, delete the old key from the service account to ensure it cannot be used for unauthorized access.

gcloud iam service-accounts keys delete OLD_KEY_ID --iam-account=YOUR_SERVICE_ACCOUNT_EMAIL

This process ensures that your service account keys are regularly rotated, reducing the risk of key compromise.

References

Managing Service Account Keys

Service Account Key Rotation

Objective: Quickly recover a deleted service account used for data transfers.

Solution: Use the undelete command available in the gcloud command-line tool to recover the service account.

Steps:

Step 1: Open the Cloud Shell in the Google Cloud Console.

Step 2: Run the following command to list the deleted service accounts:

gcloud iam service-accounts list --filter="deleted: true"

Step 3: Identify the name and ID of the deleted service account.

Step 4: Use the undelete command to recover the service account:

gcloud iam service-accounts undelete [SERVICE_ACCOUNT_ID]

Step 5: Verify that the service account has been restored and reassign any necessary permissions.

By using the undelete command, you can quickly restore the service account and resume application functionality without compromising security.