The problem requires granting an external partner team access solely to a database, without extending to other network resources, and following Google-recommended practices.
Workforce Identity Federation: This Google Cloud IAM feature is specifically designed for scenarios where an organization needs to grant Google Cloud access to external identities (like partners, contractors, or customers) who are managed by their own identity provider (IdP). It allows these external users to authenticate using their existing credentials and then gain access to specified Google Cloud resources.
Extract Reference: "Workforce Identity Federation lets you use an external identity provider (IdP) to authenticate and authorize a workforce-a group of users, such as employees, partners, and contractors- using IAM, so that the users can access Google Cloud services." (Google Cloud Documentation: "Workforce Identity Federation | IAM Documentation" - https://cloud.google.com/iam/docs/workforce-identity-federation) Extract Reference: "Secure access for partners and vendors. Workforce Identity Federation can enable enterprises to selectively federate users from partner or vendor IdPs without requiring IT teams to sync or create a separate identity store to use Google Cloud resources." (Google Cloud Documentation: "Introducing Workforce Identity Federation..." - https://www.azalio.io/introducing-workforce-identity-federation-to-easily- manage-workforce-access-to-google-cloud/) Least Privilege and Isolation: With Workforce Identity Federation, you create an identity pool and a provider that trusts the partner's IdP. You then grant IAM roles only to the workforce pool (or specific identities within it) on the specific database resource. This ensures fine-grained access control and prevents access to other resources in your network, directly addressing the least privilege and isolation requirements. The partner's identities are never synced into your internal Cloud Identity directory.
Let's evaluate the other options:
A). Add a public IP address... Securely distribute credentials: Adding a public IP address exposes the database to the internet, which is a major security risk and contradicts "restricted solely to the database and can not extend to any other resources within your company's network" as it allows any external network to potentially reach it. Distributing credentials manually is also not a Google-recommended secure practice.
B). Create accounts for the partner team in your corporate identity provider. Synchronize these accounts with Google Cloud Identity: This means you become responsible for managing the partner's identities within your own corporate IdP and syncing them. This is an unnecessary operational burden and blurs the lines of identity management. It also may inadvertently grant them broader network access if your corporate IdP is connected to your internal network resources.
C). Ask the partner team to set up Cloud Identity accounts within their own corporate environment and identity provider. Grant the partner's Cloud Identity accounts access: While better than B, this implies the partner managing Cloud Identity accounts themselves and you directly granting IAM roles to their Cloud Identity users. Workforce Identity Federation is a more robust and scalable solution for federating any external IdP with Google Cloud IAM, rather than requiring partners to adopt Cloud Identity directly. Workforce Identity Federation is the explicit pattern for cross-organization access using existing external IdPs.
Therefore, Workforce Identity Federation is the most secure, scalable, and Google-recommended solution for granting restricted access to external partner teams.

* External HTTP(S) Load Balancer: Deploy an external HTTP(S) load balancer to manage traffic to your VMs. This load balancer will handle incoming traffic from the internet while the VMs themselves do not have public IP addresses.
* Host (VPC) Project Deployment: Deploy the load balancer in the host (VPC) project. This allows for centralized management of network resources and maintains the integrity of your shared VPC configuration.
* Backend Configuration: Configure the MIG as the backend for the load balancer. This setup ensures that the VMs can still serve external users while reducing their direct exposure to the internet. This solution provides the required access to external users through the load balancer, enhancing security by not exposing individual VM IP addresses. References:
* Google Cloud - External HTTP(S) Load Balancer Overview
* Google Cloud - Shared VPC Overview

The Standard Tier network only provides regional load balancing, while the Premium Tier supports global load balancing with a single anycast IP address. To distribute requests across multiple regions, you need to use the Premium Tier and update the load balancer configuration accordingly.
Steps:
* Upgrade to Premium Tier: Update the load balancer to use the Premium Tier network in the Google Cloud Console.
* Add New Instance Group: Add the instance group in the new region (us-east-2) to the backend configuration of the existing load balancer.
* Verify Configuration: Ensure that the frontend configuration of the load balancer uses a single external IP address for global distribution.
References:
* Google Cloud: Global load balancing

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

Comprehensive and Detailed Explanation From Exact Extract:
The requirements are runtime threat detection for containers that specifically detects activities like loading additional libraries or executing malicious scripts, with findings visible in Security Command Center (SCC).
Container Threat Detection (CTD) is the specific SCC service component designed to monitor container runtimes for suspicious events like reverse shells, suspicious library loading, and execution of malicious scripts. It is available only with the Security Command Center Premium tier.
Extracts:
"Container Threat Detection (CTD) is a Security Command Center Premium service that provides runtime threat detection for Google Kubernetes Engine (GKE) and Kubernetes clusters." (Source 4.1)
"CTD detects specific runtime events, such as: Execution of malicious scripts... Loading of suspicious libraries... CTD creates high-fidelity Security Command Center findings for these threats." (Source 4.2)
"Security Health Analytics (Option C) identifies misconfigurations and compliance violations, such as overly permissive IAM roles or open firewall ports, but it does not perform runtime threat detection." (Source 4.3) While using log-based metrics (Option D) is possible, enabling CTD (Option B) is the specific, managed, and authoritative way to generate verified runtime threat findings directly within Security Command Center as required by the prompt.