Azure Fundamentals (Describe the core Azure architectural components )

Benefits and usage of Regions and Region Pairs :

Regions :

Within the United States geography, there are many regions, including the Central US region in Iowa, the East US region in Virginia, the West US region in California, and the South Central US region in Texas.

Microsoft also operates isolated regions that are completely dedicated to government data because of the additional regulations that governmental data requires.

Regional Pair :

Each regional pair contains two regions within the geography. When Microsoft has to perform updates to the Azure platform, they perform those updates on one region in the regional pair. Once those updates are complete, they move to the next region in the regional pair.

This ensures that your services operating within a regional pair aren’t impacted by updates.

The fact that each geography contains at least two regions separated by a large physical distance is important. That’s how Azure maintains disaster recovery.

In order to ensure that applications are still performing as quickly as possible, Microsoft guarantees round-trip network performance of 2 milliseconds or less between regions.

benefits and usage of Availability Zones :

Important that data and applications maintain availability when a problem occurs at a particular datacenter within a region. For that reason, Microsoft developed availability zones.

Azure Availability Zone — made up of one or more datacenter. Physically seperated.!

Currently, availability zones are supported with the following Azure services: docs.microsoft.com/en-us/azure/availability..

Don’t confuse availability zones with availability sets

Availability sets

Allow you to create two or more virtual machines in different physical server racks in an Azure datacenter. Microsoft guarantees a 99.95 percent SLA with an availability set.

Availability zone

Allows you to deploy two or more Azure services into two distinct datacenters within a region. Microsoft guarantees a 99.99 percent SLA with availability zones.

Benefits and usage of Resource Groups :

The resource group collects metadata from each individual resource to facilitate more granular management. This not only has advantages for administration and cost management, but also for applying role-based access controls.

Note : A Resource group required to be created first before you created resources

If you have access to multiple Azure subscriptions, you can also have resources from multiple subscriptions in a single resource group.

An Azure resource can only exist in one resource group. In other words, you can’t have a virtual machine ( ABCD) in a resource group called Development and also in a resource group called Production. because it must be in one group or the other. You can move Azure resources from one resource group to another

Benefits and usage of Subscriptions :

Azure subscription is like an azure account, You get billed per subscription.

Each Azure subscription has limits (sometimes called quotas) assigned to it.

For example, you can have up to 250 Azure Storage accounts per region in a subscription, up to 25,000 virtual machines per region, and up to 980 resource groups per subscription across all regions.

Microsoft support can increase limits in some scenarios if you have a good business justification. Some limits, however, cannot be increased.

Free Trial Provides free access to Azure resources for a limited time.

Pay-As-You-Go You pay only for those resources you use in Azure. There’s no up-front cost, and you can cancel the subscription at any time.

Pay-As-You-Go Dev. / Test A special subscription for subscribers to Visual Studio that can be used for development and testing. This subscription offers discounted rates on VMs, but you cannot use this for production applications.

Each subscription is associated with a unique identifier called a subscription ID. You can give each subscription a descriptive name to help you identify it, but Azure will always use the subscription ID to identify your subscription. When you talk to Microsoft about your Azure account, they’ll also often ask for your subscription ID.

Benefits and usage of Management groups :

A convenient way to apply policies and access control to your Azure resources. Much like a resource group, a management group is a container for organizing your resources. However, management groups can contain only Azure subscriptions or other management groups.

By organizing the subscriptions using management groups, you can have more control over who has access to which resources. You can also control the configuration of resources created within those subscriptions.

There are, however, a few limitations: You’re limited to a total of 10,000 management groups. A management group hierarchy can only support up to six levels. You cannot have multiple parents for a single management group or subscription.

In order to make it easier to deploy and manage Azure services, Microsoft developed Azure Resource Manager, or ARM.

Benefits and usage of Azure Resource Manager :

ARM is a service that runs in Azure, and it’s responsible for all interaction with Azure services. When you create a new Azure service, ARM authenticates you to make sure you have the right access to create that resource, and then it talks to a resource provider for the service you’re creating. For example, if you’re creating a new web app in Azure App Service, ARM will pass your request on to the Microsoft. Web resource provider because it knows all about web apps and how to create them.

With and Azure resource manager you can.

Manager your infrastructure through declarative templates rather than scripts.
Deploy, manage, and monitor all the resources for your solution as a group, rather than handling these resources individually.
Define the dependencies between resources so they're deployed in the correct order.
Apply tags to resources to logically organize all the resources in your subscription.

Some imp Notes on this chapter :

A resource in azure can only be a part of a single resource group.

Assigning tags to resource groups is not inherited by the resources within.

You cannot nest resource groups together

Assigning permissions to the resources groups is inherited by the resources within.

Resources in resource group does not inherit the same tag assigned to its resource group.

Azure Resources can also access resources from another resource group and from multiple azure regions.

Deleting an Azure resource group can delete all the resources within that group.

Resource groups have no cost associated with them.

Availability zone(identical VMs in multiple DCs in a region) and Availability sets(identical VMs within a same DC) for virtual machines. You can either choose one of these two.

Availability zones are currently not available in all regions.