Oracle Cloud Infrastructure Foundations 2020 Associate

Creating a manual cluster of compute instances, and Writing custom scripts that will monitor your solution are not valid ways to ensure fault tolerance at all. Also, Performing Data Integrity check when using OCI File Storage Service is not valid since OCI takes care of it.
Therefore, we are left with:
1) Using multiple OCI Availibility Domains (AD), where available, to deploy your solution - Which is excellent because we have multiple AD's so that if one fails, we have a backup AD!
2) Ensuring your solution components are distributed across OCI Fault Domains - So that we can protect our deployment against unexpected power failures, AD failure etc.
References:
https://blogs.oracle.com/cloud-infrastructure/using-availibility-domains-and-fault-domains-to-
improve-application-resiliency

When creating a compartment, you must provide a name for it (maximum 100 characters, including letters, numbers, periods, hyphens, and underscores) that is unique within its parent compartment. You must also provide a description, which is a non-unique, changeable description for the compartment, from 1 through 400 characters. Oracle will also assign the compartment a unique ID called an Oracle Cloud ID.
You can create subcompartments in compartments to create hierarchies that are six levels deep.

References:
https://docs.cloud.oracle.com/en-us/iaas/Content/Identity/Tasks/managingcompartments.htm
When you first start working with Oracle Cloud Infrastructure, you need to think carefully about how you want to use compartments to organize and isolate your cloud resources. Compartments are fundamental to that process. Most resources can be moved between compartments. However, it's important to think through your compartment design for your organization up front, before implementing anything. For more information, see Setting Up Your Tenancy. The Console is designed to display your resources by compartment within the current region. When you work with your resources in the Console, you must choose which compartment to work in from a list on the page. That list is filtered to show only the compartments in the tenancy that you have permission to access. If you're an administrator, you'll have permission to view all compartments and work with any compartment's resources, but if you're a user with limited access, you probably won't. Compartments are tenancy-wide, across regions. When you create a compartment, it is available in every region that your tenancy is subscribed to. You can get a cross-region view of your resources in a specific compartment with the compartment explorer. See Viewing All Resources in a Compartment. You can create subcompartments in compartments to create hierarchies that are six levels deep.

References:
https://docs.cloud.oracle.com/en-us/iaas/Content/Identity/Tasks/managingcompartments.htm

The Oracle Cloud Infrastructure Domain Name System (DNS) service lets you create and manage your DNS zones. You can create zones, add records to zones, and allow Oracle Cloud Infrastructure's edge network to handle your domain's DNS queries.

References:
https://www.oracle.com/a/ocom/docs/cloud/edge-services-100.pdf

Oracle Cloud Infrastructure Container Engine for Kubernetes is a fully-managed, scalable, and highly available service that you can use to deploy your containerized applications to the cloud. Use Container Engine for Kubernetes (sometimes abbreviated to just OKE) when your development team wants to reliably build, deploy, and manage cloud-native applications. You specify the compute resources that your applications require, and Container Engine for Kubernetes provisions them on Oracle Cloud Infrastructure in an existing OCI tenancy. Container Engine for Kubernetes uses Kubernetes - the open-source system for automating deployment, scaling, and management of containerized applications across clusters of hosts. Kubernetes groups the containers that make up an application into logical units (called pods) for easy management and discovery. You can access Container Engine for Kubernetes to define and create Kubernetes clusters using the Console and the REST API. You can access the clusters you create using the Kubernetes command line (kubectl), the Kubernetes Dashboard, and the Kubernetes API. Container Engine for Kubernetes is integrated with Oracle Cloud Infrastructure Identity and Access Management (IAM), which provides easy authentication with native Oracle Cloud Infrastructure identity functionality.

References:
https://docs.cloud.oracle.com/en-us/iaas/Content/ContEng/Concepts/contengoverview.htm

Oracle Cloud Infrastructure Container Engine for Kubernetes is a fully-managed, scalable, and highly available service that you can use to deploy your containerized applications to the cloud. Use Container Engine for Kubernetes (sometimes abbreviated to just OKE) when your development team wants to reliably build, deploy, and manage cloud-native applications. You specify the compute resources that your applications require, and Container Engine for Kubernetes provisions them on Oracle Cloud Infrastructure in an existing OCI tenancy. You can access Container Engine for Kubernetes to define and create Kubernetes clusters using the Console and the REST API. You can access the clusters you create using the Kubernetes command line (kubectl), the Kubernetes Dashboard, and the Kubernetes API. Container

Engine for Kubernetes is integrated with Oracle Cloud Infrastructure Identity and Access Management (IAM), which provides easy authentication with native Oracle Cloud Infrastructure identity functionality.
References:
https://docs.cloud.oracle.com/en-us/iaas/Content/ContEng/Concepts/contengoverview.htm

Here is the official list of all industry standards that OCI complies with :
https://www.oracle.com/in/cloud/cloud-infrastructure-compliance/

To design a high availability architecture, three key elements should be considered-- redundancy, monitoring, and failover:
1) Redundancy means that multiple components can perform the same task. The problem of a single point of failure is eliminated because redundant components can take over a task performed by a component that has failed.
2) Monitoring means checking whether or not a component is working properly.
3) Failover is the process by which a secondary component becomes primary when the primary
component fails.
The best practices introduced here focus on these three key elements. Although high availability can be achieved at many different levels, including the application level and the cloud infrastructure level, here we will focus on the cloud infrastructure level. An Oracle Cloud Infrastructure region is a localized geographic area composed of one or more availability domains, each composed of three fault domains. High availability is ensured by a redundancy of fault domains within the availability domains. An availability domain is one or more data centers located within a region. Availability domains are isolated from each other, fault tolerant, and unlikely to fail simultaneously. Because availability domains do not share physical infrastructure, such as power or cooling, or the internal availability domain network, a failure that impacts one availability domain is unlikely to impact the availability of others. A fault domain is a grouping of hardware and infrastructure within an availability domain. Each availability domain contains three fault domains. Fault domains let you distribute your instances so that they are not on the same physical hardware within a single availability domain. As a result, an unexpected hardware failure or a Compute hardware maintenance that affects one fault domain does not affect instances in other fault domains. You can optionally specify the fault domain for a new instance at launch time, or you can let the system select one for you. All the availability domains in a region are connected to each other by a low-latency, high bandwidth network. This predictable, encrypted interconnection between availability domains provides the building blocks for both high availability and disaster recovery.
References:
https://docs.oracle.com/en/solutions/design-ha/index.html#GUID-76ECDDB4-4CB1-4D93-9A6D-A8B620F72369

A shape is a template that determines the number of CPUs, amount of memory, and other resources that are allocated to an instance.
The network bandwidth is directly proportional to the number of OCPUs in the instance shape!

References:
https://docs.cloud.oracle.com/en-us/iaas/Content/Compute/References/computeshapes.htm

A NAT gateway gives cloud resources without public IP addresses access to the internet without exposing those resources to incoming internet connections.

References:
https://docs.cloud.oracle.com/en-us/iaas/Content/Network/Tasks/NATgateway.htm