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

Comprehensive and Detailed In Depth Explanation:

The problem states that a subnet is nearing its IP address capacity, and the requirement is to expand it without downtime and with minimal operational cost, following Google-recommended practices.

A. Creating a second VPC with the same subnet IP range and peering: While VPC Network Peering allows communication between VPCs, having overlapping IP ranges is generally not recommended and can lead to routing complexities if not managed carefully. It also adds operational overhead of managing two VPCs. This is not the most straightforward or cost-effective solution for simply expanding IP capacity within the same logical network.

B. Deleting and recreating the subnet: Deleting a subnet that contains active VM instances will cause downtime for those instances, violating a key requirement.

C. Using the Google Cloud CLI tool to expand the primary IP range of your subnet: Google Cloud allows you to expand the primary IP range of an existing subnet after it's created, as long as there are no conflicting subnets in the VPC. This operation does not require deleting the subnet or restarting the existing VMs within it, thus avoiding downtime. It's a direct and cost-effective way to increase the available IP address space within the existing subnet. This is a Google-recommended practice for handling subnet capacity issues.

D. Permitting additional traffic with firewall rules: Firewall rules control network traffic based on IP ranges, protocols, and ports. They do not increase the number of available private IP addresses within the subnet. This option does not address the core issue of IP address exhaustion.

Therefore, expanding the primary IP range of the existing subnet using the Google Cloud CLI is the recommended solution that meets all the requirements: addressing IP capacity, minimizing operational costs, and avoiding downtime.

Google Cloud Documentation References:

Expanding Subnet IP Ranges: https://cloud.google.com/vpc/docs/expand-subnet - This documentation explicitly describes how to expand the IP range of an existing subnet without downtime. It outlines the prerequisites and steps involved using the gcloud CLI or the Google Cloud Console.

VPC Network Overview: https://cloud.google.com/vpc/docs/vpc - Provides context on subnet IP ranges and their management.

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Navigate to Stackdriver Logging and select resource.labels.project_id=*. is not right.

Log entries are held in Stackdriver Logging for a limited time known as the retention period  which is 30 days (default configuration). After that, the entries are deleted. To keep log entries longer, you need to export them outside of Stackdriver Logging by configuring log sinks.

Ref: https://cloud.google.com/blog/products/gcp/best-practices-for-working-with-google-cloud-audit-logging

Configure a Cloud Scheduler job to read from Stackdriver and store the logs in BigQuery. Configure the table expiration to 60 days. is not right.

While this works, it makes no sense to use Cloud Scheduler job to read from Stackdriver and store the logs in BigQuery when Google provides a feature (export sinks) that does exactly the same thing and works out of the box.

Ref: https://cloud.google.com/logging/docs/export/configure_export_v2

Create a Stackdriver Logging Export with a Sink destination to Cloud Storage. Create a lifecycle rule to delete objects after 60 days. is not right.

You can export logs by creating one or more sinks that include a logs query and an export destination. Supported destinations for exported log entries are Cloud Storage, BigQuery, and Pub/Sub.

Ref: https://cloud.google.com/logging/docs/export/configure_export_v2

Sinks are limited to exporting log entries from the exact resource in which the sink was created: a Google Cloud project, organization, folder, or billing account. If it makes it easier to exporting from all projects of an organication, you can create an aggregated sink that can export log entries from all the projects, folders, and billing accounts of a Google Cloud organization.

Ref: https://cloud.google.com/logging/docs/export/aggregated_sinks

Either way, we now have the data in Cloud Storage, but querying logs information from Cloud Storage is harder than Querying information from BigQuery dataset. For this reason, we should prefer Big Query over Cloud Storage.

Create a Stackdriver Logging Export with a Sink destination to a BigQuery dataset. Configure the table expiration to 60 days. is the right answer.

You can export logs by creating one or more sinks that include a logs query and an export destination. Supported destinations for exported log entries are Cloud Storage, BigQuery, and Pub/Sub.

Ref: https://cloud.google.com/logging/docs/export/configure_export_v2

Sinks are limited to exporting log entries from the exact resource in which the sink was created: a Google Cloud project, organization, folder, or billing account. If it makes it easier to exporting from all projects of an organication, you can create an aggregated sink that can export log entries from all the projects, folders, and billing accounts of a Google Cloud organization.

Ref: https://cloud.google.com/logging/docs/export/aggregated_sinks

Either way, we now have the data in a BigQuery Dataset. Querying information from a Big Query dataset is easier and quicker than analyzing contents in Cloud Storage bucket. As our requirement is to Quickly analyze the log contents, we should prefer Big Query over Cloud Storage.

Also, You can control storage costs and optimize storage usage by setting the default table expiration for newly created tables in a dataset. If you set the property when the dataset is created, any table created in the dataset is deleted after the expiration period. If you set the property after the dataset is created, only new tables are deleted after the expiration period.

For example, if you set the default table expiration to 7 days, older data is automatically deleted after 1 week.

Ref: https://cloud.google.com/bigquery/docs/best-practices-storage