Google Updated Associate-Cloud-Engineer Exam Questions and Answers by harriett

As part of your workload, there might be certain VM instances that are critical to running your application or services, such as an instance running a SQL server, a server used as a license manager, and so on. These VM instances might need to stay running indefinitely so you need a way to protect these VMs from being deleted. By setting the deletionProtection flag, a VM instance can be protected from accidental deletion. If a user attempts to delete a VM instance for which you have set the deletionProtection flag, the request fails. Only a user that has been granted a role with compute.instances.create permission can reset the flag to allow the resource to be deleted.

Ref: https://cloud.google.com/compute/docs/instances/preventing-accidental-vm-deletion

Comprehensive and Detailed In Depth Explanation:

Let's evaluate each database option against the requirements: automatic scaling, multi-region support, and low latency for a growing social media platform:

A. Bigtable: Bigtable is a highly scalable NoSQL database designed for large analytical and operational workloads with low latency. It offers excellent horizontal scalability and can be deployed across multiple regions for high availability and lower latency for a global user base. However, it's a NoSQL database and might require significant changes to your existing PostgreSQL data model and application code.

B. BigQuery: BigQuery is a fully managed, serverless data warehouse optimized for analytical queries on large datasets. It's not designed for low-latency transactional workloads that a social media platformwould require for real-time user interactions. While it's globally available, its primary use case is not operational database needs.

C. Spanner: Spanner is a globally distributed, horizontally scalable relational database service with strong consistency. It offers automatic scaling, built-in multi-region and multi-continental configurations for high availability and low latency across a global user base, and supports standard SQL (with some extensions). This makes it a strong candidate for a rapidly growing platform needing scalability, global presence, and low latency. While it's not directly PostgreSQL, it offers a relational model and tools to aid migration.

D. Cloud SQL for PostgreSQL: Cloud SQL offers managed PostgreSQL instances with automatic scaling capabilities. It supports high availability within a region and cross-region read replicas for disaster recovery and read scaling. However, its multi-region capabilities for write operations and automatic scaling across regions are more limited compared to Spanner. For a rapidly growing platform with a primarily North American user base but future global expansion in mind and a need for low latency, Spanner's architecture is better suited for true multi-region write capabilities and consistent low latency globally.

Considering the requirements for automatic scaling, multi-region support for both reads and writes with low latency for a growing user base, Spanner is the most appropriate choice.

Google Cloud Documentation References:

Cloud Spanner Overview: https://cloud.google.com/spanner/docs/overview - This document highlights Spanner 's global scalability, strong consistency, and multi-region capabilities.

Cloud Bigtable Overview: https://cloud.google.com/bigtable/docs/overview - While scalable and low-latency, it 's a NoSQL database, which might require significant application changes.

BigQuery Overview: https://cloud.google.com/bigquery/docs/introduction - Focuses on analytics, not low-latency transactional workloads.

Cloud SQL for PostgreSQL Overview: https://cloud.google.com/sql/docs/postgres/overview - While it offers scaling and regional HA, its multi-region write capabilities are not as robust as Spanner 's.

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Before you run the gcloud compute instances list command, you need to do two things: authenticate with your user account and set the default project for gcloud CLI.

To authenticate with your user account, you need to run gcloud auth login, enter your login credentials in the dialog window, and paste the received login token to gcloud CLI. This will authorize the gcloud CLI to access Google Cloud resources on your behalf1.

To set the default project for gcloud CLI, you need to run gcloud config set project $my_project, where $my_project is the ID of the project that contains the instances you want to list. This will saveyou from having to specify the project flag for every gcloud command2.

Option B is not recommended, because using a service account key increases the risk of credential leakage and misuse. It is also not necessary, because you can use your user account to authenticate to the gcloud CLI3. Option C is not correct, because there is no such thing as a Cloud Identity user account key. Cloud Identity is a service that provides identity and access management for Google Cloud users andgroups4. Option D is not required, because the gcloud compute instances list command does not depend on the default zone. You can list instances from all zones or filter by a specific zone using the --filter flag.

1: https://cloud.google.com/sdk/docs/authorizing

2: https://cloud.google.com/sdk/gcloud/reference/config/set

3: https://cloud.google.com/iam/docs/best-practices-for-managing-service-account-keys

4: https://cloud.google.com/identity/docs/overview

https://cloud.google.com/sdk/gcloud/reference/compute/instances/list