Google Associate-Cloud-Engineer - Google Cloud Certified - Associate Cloud Engineer

Best practices for persistent disk snapshots

You can create persistent disk snapshots at any time, but you can create snapshots more quickly and with greater reliability if you use the following best practices.

Creating frequent snapshots efficiently

Use snapshots to manage your data efficiently.

Create a snapshot of your data on a regular schedule to minimize data loss due to unexpected failure.

Improve performance by eliminating excessive snapshot downloads and by creating an image and reusing it.

Set your snapshot schedule to off-peak hours to reduce snapshot time.

Snapshot frequency limits

Creating snapshots from persistent disks

You can snapshot your disks at most once every 10 minutes. If you want to issue a burst of requests to snapshot your disks, you can issue at most 6 requests in 60 minutes.

If the limit is exceeded, the operation fails and returns the following error:

https://cloud.google.com/compute/docs/disks/snapshot-best-practices

https://cloud.google.com/appengine/docs/flexible/managing-projects-apps-billing#:~:text=Each%20Cloud%20project%20can%20contain%20only%20a%20single%20App%20Engine%20application%2C%20and%20once%20created%20you%20cannot%20change%20the%20location%20of%20your%20App%20Engine%20application.

Two App engine can't be running on the same project: you can check this easy diagram for more info:https://cloud.google.com/appengine/docs/standard/an-overview-of-app-engine#components_of_an_application

And you can't change location after setting it for your app Engine.https://cloud.google.com/appengine/docs/standard/locations

App Engine is regional and you cannot change an apps region after you set it. Therefore, the only way to have an app run in another region is by creating a new project and targeting the app engine to run in the required region (asia-northeast1 in our case).

Ref: https://cloud.google.com/appengine/docs/locations

Comprehensive and Detailed In Depth Explanation:

The requirement is to export logs from Cloud Logging to a third-party SaaS tool with the least amount of delay possible. Let's analyze each option:

A. Cloud Scheduler, Cloud Function, and querying Cloud Logging: This approach introduces a delay based on the Cloud Scheduler's cron job frequency. The Cloud Function would periodically query Cloud Logging, which might not capture the logs in real-time. This does not meet the "least amount of delay possible" requirement.

B. Cloud Logging sink to Pub/Sub, SaaS tool subscribing to Pub/Sub: Cloud Logging sinks can be configured to export logs in near real-time as they are ingested into Cloud Logging. Pub/Sub is a messaging service designed for asynchronous and near real-time message delivery. By configuring the sink to send logs to a Pub/Sub topic, and having the SaaS tool subscribe to this topic, logs can be delivered to the SaaS tool with minimal delay. This aligns with the requirement for immediate export.

C. Cloud Logging sink to Cloud Storage, SaaS tool reading Cloud Storage: Exporting logs to Cloud Storage involves a batch-oriented approach. Logs are typically written to files periodically. The SaaS tool would then need to poll or be configured to read these files, introducing a significant delay compared to a streaming approach.

D. Cloud Logging sink to BigQuery, SaaS tool querying BigQuery: Similar to Cloud Storage, exporting to BigQuery is more suitable for analytical purposes. The SaaS tool would need to periodically queryBigQuery, which introduces latency and is not the most efficient way to achieve near real-time log delivery.

Therefore, configuring a Cloud Logging sink to Pub/Sub and having the SaaS tool subscribe to the Pub/Sub topic provides the lowest latency for exporting logs.

Google Cloud Documentation References:

Cloud Logging Sinks Overview: https://cloud.google.com/logging/docs/export/configure_export_v2 - This document explains how to create and manage Cloud Logging sinks, including the available destinations.

Pub/Sub Overview: https://cloud.google.com/pubsub/docs/overview - This highlights Pub/Sub 's capabilities for real-time message delivery and its use cases in streaming data.

Exporting Logs with Cloud Logging: https://cloud.google.com/logging/docs/export - This provides a comprehensive guide to exporting logs from Cloud Logging to various destinations, emphasizing Pub/Sub for streaming.

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https://cloud.google.com/compute/docs/autoscaler#specifications

Autoscaling works independently from autohealing. If you configure autohealing for your group and an instance fails the health check, the autohealer attempts to recreate the instance. Recreating an instance can cause the number of instances in the group to fall below the autoscaling threshold (minNumReplicas) that you specify.

Since we need the application running at all times, we need a minimum 1 instance.

Only a single instance of the VM should run, we need a maximum 1 instance.

We want the application running at all times. If the VM crashes due to any underlying hardware failure, we want another instance to be added to MIG so that application can continue to serve requests. We can achieve this by enabling autoscaling. The only option that satisfies these three is Set autoscaling to On, set the minimum number of instances to 1, and then set the maximum number of instances to 1.

Ref: https://cloud.google.com/compute/docs/autoscaler

To set a default cluster for gcloud commands, run the following command: gcloud config set container/cluster CLUSTER_NAMEhttps://cloud.google.com/kubernetes-engine/docs/how-to/managing-clusters?hl=en

Choosing a region and zone You choose which region or zone hosts your resources, which controls where your data is stored and used. Choosing a region and zone is important for several reasons:

Handling failures

Distribute your resources across multiple zones and regions to tolerate outages. Google designs zones to be independent from each other: a zone usually has power, cooling, networking, and control planes that are isolated from other zones, and most single failure events will affect only a single zone. Thus, if a zone becomes unavailable, you can transfer traffic to another zone in the same region to keep your services running. Similarly, if a region experiences any disturbances, you should have backup services running in a different region. For more information about distributing your resources and designing a robust system, see Designing Robust Systems. Decreased network latency To decrease network latency, you might want to choose a region or zone that is close to your point of service.https://cloud.google.com/compute/docs/regions-zones#choosing_a_region_and_zone

https://cloud.google.com/compute/docs/disks/local-ssd

Google Cloud Coldline is a new cold-tier storage for archival data with access frequency of less than once per year. Unlike other cold storage options, Nearline has no delays prior to data access, so now it is the leading solution among competitors.

The Real description is about Coldline storage Class:

Coldline Storage

Coldline Storage is a very-low-cost, highly durable storage service for storing infrequently accessed data. Coldline Storage is a better choice than Standard Storage or Nearline Storage in scenarios where slightly lower availability, a 90-day minimum storage duration, and higher costs for data access are acceptable trade-offs for lowered at-rest storage costs.

Coldline Storage is ideal for data you plan to read or modify at most once a quarter. Note, however, that for data being kept entirely for backup or archiving purposes, Archive Storage is more cost-effective, as it offers the lowest storage costs.

https://cloud.google.com/storage/docs/storage-classes#coldline