Azure tenants, AD and subscriptions - azure

I am a little bit confused about Azure tenants, AD and subscriptions.
Imagine a customer starting from scratch.
Can I say that the first step is creating (subscribing) a tenant?
After creating a tenant, is there a default AD? Can they create other ADs inside the same tenamt?
Can they create more subscriprions for a single tenant?
Given they can, can a subscription be associated to one or more ADs?
Is there any page or document describing the concepts and the design of Azure components (tenants, AD and subscriptions)?
Regards
marius

When you signed up to Azure using a Microsoft account, then you will get Azure with a Default Directory. A tenant is associated with a single identity (person, company, or organization) and can own one or several subscriptions. Single tenant can have multiple Active directories, but a single directory can only have 1 tenant.
There is similar SO question which can help you in understanding more.

Related

Managed Identity in B2B scenario across different subscription?

Can managed identity be configured for accessing Azure resources across different Azure subscriptions?
Could you point me out in right direction, isn't Azure federation supposed to take care of this?
Seems not feasible based on my R & D as well.
Do I seem to be overestimating this Azure AD feature.
Accounts in any organizational directory?
Based on your and my comment:
Comment Question: is those subscriptions on same Azure AD tenants?
Comment Answer: No. Thinks of all together different Business Org. Different subscription
My Answer to your question is:
Managed identities exist in the Azure AD tenant as service principals. It is therefore can only be assigned access to any subscription connected to that Azure AD tenant.
So in short, if the subscriptions are connected to different Azure AD tenants, it wont be possible to achieve what you are asking about as far as I know.
EDIT
In addition to your comment
Comment: Can managed identity be used if all tenants were in same subscription?
My answer is: Each subscription can only belong to one tenant. please check Microsoft doc https://learn.microsoft.com/en-us/microsoft-365/enterprise/subscriptions-licenses-accounts-and-tenants-for-microsoft-cloud-offerings?view=o365-worldwide
Note: if this is feasible by one or other way and there are answer that can show the opposite of my experience and knowledge, I will be glad to know that as well.

What does it mean to be an Instance of the Azure Active Directory?

Microsoft says, "In Azure Active Directory a tenant is an instance of Azure Active Directory that an organization receives when it signs up for a cloud application like Microsoft 365."
Could anyone explain what it means for a tenant to be an instance of the Azure Active Directory?
I know that an instance is basically a virtual machine. However, I'm failing to see how that definition applies in this particular context.
In your context, Instance of Azure Active Directory means Azure tenant.
I agree with #Peter Bons, Azure tenant is a dedicated and trusted instance of Azure AD.
Tenant refers to a single instance of Azure Active Directory.
Please note that tenant will be automatically created when your organization signs up for a Microsoft cloud service subscription.
To make it simple, you can consider it as parent group that includes users and groups along with the access control to application and resources.
A tenant is associated with a single identity and can have one or several subscriptions.
Based on your requirement, you can have single tenant or multitenant.
Every tenant is linked to a single Azure AD instance, which is shared with all tenant's subscriptions.
Azure AD Tenants are globally unique and have scopes with a domain name ending with ‘onmicrosoft.com’ and has a Tenant ID in the form of UUID/GUID.
For more in detail, please refer below links:
Understanding Tenants, Subscriptions, Regions and Geographies in Azure – siliconvalve
What is Azure Active Directory Tenant and How to create (azurelib.com)

How to configure my AAD for a stand-alone web application when using AAD for organization?

We have an Office 365 tenant that we are using for our basic AD functions (joining desktop PC's, authentication, etc..) for our organization.
We're also building a stand-alone mobile and web application. We have an Azure subscription we've tied to our primary AAD tenant. And we're likely to have a separate dev/test subscription.
We're wanting to join our applications resources to an AAD for management purposes, but my question is should we join these to our regular AAD? I don't think that's wise. So what are the alternatives? Create another AAD? We plan to use Azure B2C for the web and mobile authentication.
Do we create another tenant? Partition our primary tenant off in some way (like traditional AD forests and trees)?
I'm trying to keep the application isolated for security purposes from our organizations usage.
FYI, we do not have any on-prem legacy AD.
This depends on what the purpose of your applications are. if you are selling your application and creating a multitenant application, etc. There may be a case for separate tenants (B2C).
But in general, try to avoid creating too many tenants, it can become a management nightmare.
Now to answer some of your specific questions. When you create azure b2c, it is actually a new AAD Tenant, with a different domain name.
In terms of the dev/test subscription, it should be a subscription tied to the same AAD tenant. You would not create a separate tenant for that. unless you absolutely need to test things with a totally separate Directory (eg, editing random Global Azure AD settings that you don't want to do in your primary tenant) but again, that means it becomes a management nightmare as 1: you don't want to create multiple users in different tenants for the same person. This means you'll need to use azure b2b, to federate users and setup separate permissions, etcetc.
In azure Ad you cannot create child domains, that concept is different from on-prem AD. its just not how it works.
Here's a good read on some of the rarer scenarios to create more tenants:
https://itconnect.uw.edu/wares/msinf/aad/new-aad-tenant/
If you plan to use B2C then the app registration should be done there. You can later federate with your primary AD tenant.

What is the difference between an Azure tenant and Azure subscription?

I am struggling to distinguish how an Azure Subscription and an Azure tenant are different? I have tried figuring it out using examples but each time I come to the conclusion that they are the same thing in a way? If a tenant is a dedicated instance of the Azure AD service that an organization receives and owns when it signs up for a Microsoft cloud service, then is that not what a subscription is too?
Basic understanding:
a tenant is associated with a single identity (person, company, or organization) and can own one or several subscriptions
a subscription is linked to a payment setup and each subscription will result in a separate bill
in every subscription, you can add virtual resources (VM, storage, network, ...)
Additionally:
Every tenant is linked to a single Azure AD instance, which is shared with all tenant's subscriptions
Resources from one subscription are isolated from resources in other subscriptions
An owner of a tenant can decide to have multiple subscriptions:
when Subscriptions limits are reached
to use different payment methods
to isolate resources between different departments, projects, regional offices, and so on.
Example 1:
Contoso decides to have a tenant with 2 subscriptions:
one subscription for the Prod department with Credit Card A
one subscription for the Dev department with Credit Card B
(but could also be the same Credit Card as the one of another subscription)
In this example, the two departments share the same Azure AD database.
However, resources are isolated between departments, and budgets can be separated too.
Example 2:
A holding company decides to have 2 tenants:
one tenant for subsidiary Contoso with one subscription for Dev and Prod
one tenant for subsidiary Fabrikam with one subscription for Dev and another subscription for Prod
In this example, both companies have a different Azure AD database.
Example 3:
You have a tenant for your personal training.
In this tenant, you can have:
one free Azure subscription (linked to a credit card but not charged, and can be converted to a Pay-As-You-Go subscription after the free trial)
one or several Pay-As-You-Go subscriptions (linked to different credit cards)
one or several Azure Pass Sponsorship subscriptions, not linked to any credit card because these subscriptions are obtained during Microsoft trainings
one Visual Studio subscription (linked to a credit card) and with different quotas (of free resources) than the free subscription
Despite all those subscriptions have isolated resources (per subscription), and some are free while you have to pay for others, all subscriptions share the same Azure AD database.
Azure tenant is a directory. Azure subscription is an object that represents a "folder" that you can put resources in. Subscriptions are tied to tenants. so 1 tenant can have many subscriptions, but not vice versa.
Link:
https://learn.microsoft.com/en-us/azure/azure-subscription-service-limits
It helps to take a scenario:
Let's say you logged into portal.azure.com for the first time and created a free tier account.
When you login to Azure, you have a single tenant ID associated with your account which will not change unless you ask Microsoft to delete your account(this is not your Azure domain user, this is your Microsoft subscription account - eg. bob#gmail.com).
You will only have 1 subscription unless you've purchased or manage other subscriptions (by using the 'transfer billing ownership' function), then they will all be listed under subscriptions.
You will have FULL access to all "resources" associated with your tenant ID. These resources can be part of your own Azure 'directory' or from another domain that someone has given you access to.
You can create up to 20 directories, and you can belong to up to 500 directories.
When you own the subscription (eg. a free account) you'll have full rights up to the 'root' of the subscription - eg. if you click on your name in the top right corner and select "... > your permissions" you see something like:
Your account 'YOURACCOUNT#gmail.com' has been assigned the role 'User Access Administrator' (type BuiltInRole) and has access to scope /.
Your resources have Role Based Access controls that you, the subscription owner, can assign to other users in your Azure Active Directory (or other trusted directories).
By default, for a new subscription, the Account Administrator is assigned the "Service Administrator" privilege. This is 'above' the RBAC roles - there can only be one service administrator per subscription. In RBAC terms this is an 'owner'.
More points:
A single tenant can have multiple AD directories, but a single directory can only have 1 tenant.
*It is recommended to maintain only a single tenant and manage all of your AD domains from that single tenant, otherwise the user experience between domains will not be a seamless.
*A tenant is directly associated with an AD resource - if you mouse over your username in the top right corner you'll see the AD domain you're connected to and a long alphanumeric string - that's the same string in AD > properties.
*If you switch to another directory (assuming you have one) your subscription name (bob#gmail.com) doesn't change, but the tenant ID will be different.
References:
https://learn.microsoft.com/en-us/azure/role-based-access-control/rbac-and-directory-admin-roles
https://marckean.com/2016/06/01/azure-vs-azure-ad-accounts-tenants-subscriptions/
https://blogit.create.pt/miguelisidoro/2019/01/07/pros-and-cons-of-single-tenant-vs-multiple-tenants-in-office-365/
This MS doc has explained everything very nicely - Subscriptions, licenses, accounts, and tenants for Microsoft's cloud offerings
Quoting from the Summary of the hierarchy section in the documentation:
Here is a quick recap:
An organization can have multiple subscriptions
A subscription can have multiple licenses
Licenses can be assigned to individual user accounts
User accounts are stored in an Azure AD tenant
Later in the same section it says:
Multiple Microsoft cloud offering subscriptions can use the same Azure
AD tenant that acts as a common identity provider. A central Azure AD
tenant that contains the synchronized accounts of your on-premises AD
DS provides cloud-based Identity as a Service (IDaaS) for your
organization.
Let us try to understand all this with the help of a real-life example. Let's assume that I'm the owner of a company named FooBar which manufactures software products. Now here is what I'll do to setup Azure infrastructure for my company:
I'll crete an Azure account using my email id.
Then for managing the employees of the company, I created below mentioned Azure Active Directories (AAD aka tenant) in my Azure account:
PermanentAad
AdhocAad
User account of all full-time employees (FTEs) will be added into PermanentAad AAD and all temporary or contractual employees will be added into AdhocAad AAD.
Similarly, I would like to manage the billing of adhoc employees and FTEs separately. So I creates two subscriptions namely PermanenetSub and AdhocSub. I'll setup a trust relationship between PermanentAad and PermanentSub. Similarly for AdhocAad and AdhocSub. So when any FTE creates an Azure resource e.g. a virtual machine(VM) then the cost of that VM will get added to total bill in PermanentSub subscription.
Now comes the licensing part. Licenses empower a user to do things in Azure e.g. creating resources, VMs etc. I can give Enterprise Mobility + Security E5 license to an FTE so that he can create VMs for testing any stuff.
To summarize:
If you want to work in Azure you need an Azure account. To create an Azure account you need an active email id.
If you want to add people/employees or machines/devices who would be part of your IT infrastructure you need a tenant/AAD. You get one tenant/AAD by default when you create an Azure account. You can create more if you require for any kind of logical separation. AAD service is a global service spanning across all locations in Azure which manages all of our AAD instances. AAD is also known as Azure Active Directory, AAD, an Azure AD instance, an AAD Instance, an Azure AD Tenant, an AAD tenant, simply tenant or an organization, etc. They all mean the same. Therefore:
Organization == Tenant == Azure Active Directory
If you require logical separation of billing for users of your Azure account then you need multiple subscriptions. You get one subscription by default when you create a new Azure account. Subscription can be of four types as per below list:
Free
Pay-as-you-go
Enterprise agreement
Cloud Solution Provider
If you want to enable the users to do things then you issue license(s) e.g. license to be able to create VM or Azure app service. Also remember that license and Role Based Access Control (RBAC) are not same although both enable you to do things in Azure portal. But they've different nuances which you can explore on your own.
Below image summarizes the above explanation. I've taken it from the same documentation that I referred at the starting of this answer - Subscriptions, licenses, accounts, and tenants for Microsoft's cloud offerings
Quoting from the User accounts section in the documentation:
So, all the user accounts and devices of an organization reside in a common Azure AD tenant/instance.
Adding more to existing answers
Tenant is a domain, If these are email addresses of a certain company,
user#exampledomain.com
admin#exampledomain.com
The tenant can be recognized as "exampledomain", in a practical scenario you create a tenant against a company or a client.
Subscriptions are like another logical high-level grouping. For example, you can create a subscription for each environment you work with in the same tenant.
as an example, exampledomain.com tenant can have Development, QA, and Production subscriptions. Those will be billed separately according to the plans you take in
Below are succinct descriptions of key terms and the relationship between them.
They are all sourced from official Microsoft documentation.
Account
Tenant
Identity
Subscription
Resource
Resource Group
Account
To create and use Azure services, you first need to sign up [for an
Azure account].
Source:
Learning Path: Manage identity and access in Azure Active Directory
Module: Create an Azure account
Exercise: Create an Azure account
Tenant
An Azure tenant is a single dedicated and trusted instance of Azure
AD. Each tenant (also called a directory) represents a single
organization. When your organization signs up for a Microsoft cloud
service subscription, a new tenant is automatically created. Because
each tenant is a dedicated and trusted instance of Azure AD, you can
create multiple tenants or instances.
Identity
An identity is an object that can be authenticated. The identity can
be a user with a username and password. Identities can also be
applications or other servers that require authentication by using
secret keys or certificates. Azure AD is the underlying product that
provides the identity service.
Source:
Learning Path: AZ-104: Manage identities and governance in Azure
Module: Configure Azure Active Directory
Exercise: Describe Azure Active Directory concepts
Subscription
To create and use Azure services, you need an Azure
subscription...you're free to create additional subscriptions. For
example, your company might use a single Azure account for your
business and separate subscriptions for development, marketing, and
sales departments. After you've created an Azure subscription, you can start
creating Azure resources within each subscription.
Source:
Learning Path: Azure Fundamentals: Describe Azure architecture and services
Module: Get started with Azure accounts
In Azure, subscriptions are a unit of management, billing, and scale.
Similar to how resource groups are a way to logically organize
resources, subscriptions allow you to logically organize your resource
groups and facilitate billing...An account can have multiple
subscriptions, but it’s only required to have one. In a
multi-subscription account, you can use the subscriptions to configure
different billing models and apply different access-management
policies. You can use Azure subscriptions to define boundaries around
Azure products, services, and resources.
Source:
Learning Path: Azure Fundamentals: Describe Azure architecture and services
Module: Describe Azure management infrastructure
Resource
A resource is the basic building block of Azure. Anything you create,
provision, deploy, etc. is a resource. Virtual Machines (VMs), virtual
networks, databases, cognitive services, etc. are all considered
resources within Azure.
Resource Group
Resource groups are simply groupings of resources. When you create a
resource, you’re required to place it into a resource group. While a
resource group can contain many resources, a single resource can only
be in one resource group at a time. Some resources may be moved
between resource groups, but when you move a resource to a new group,
it will no longer be associated with the former group. Additionally,
resource groups can't be nested, meaning you can’t put resource group
B inside of resource group A.
Resource groups provide a convenient way to group resources together.
When you apply an action to a resource group, that action will apply
to all the resources within the resource group. If you delete a
resource group, all the resources will be deleted. If you grant or
deny access to a resource group, you’ve granted or denied access to
all the resources within the resource group.
When you’re provisioning resources, it’s good to think about the
resource group structure that best suits your needs.
For example, if you’re setting up a temporary dev environment,
grouping all the resources together means you can deprovision all of
the associated resources at once by deleting the resource group. If
you’re provisioning compute resources that will need three different
access schemas, it may be best to group resources based on the access
schema, and then assign access at the resource group level.
There aren’t hard rules about how you use resource groups, so consider
how to set up your resource groups to maximize their usefulness for
you.
Source:
Learning Path: Azure Fundamentals: Describe Azure architecture and services
Module: Describe Azure management infrastructure
Simply put, an instance of Azure AD is what an organization receives when the organization creates a relationship with Microsoft such as signing up for Azure, Microsoft Intune, or Microsoft 365.
A tenant is similar to a forest in an on-premise environment.
An Active Directory forest (AD forest) is the topmost logical container in an Active Directory configuration that contains domains, users, computers, and group policies
Think of a tenant as a user/domain entity that is registered in Azure. Tenants are Azure 'customer' - a unique entity that will be registered in Azure directories.
Subscription is an operational level of grouping resources. Tenants have subscriptions.
Tenant is quite a useful approach, which, in my opinion, is missing in AWS.

Migrate Azure AD to a new subscription

We have an Azure AD which is managed by a third party. Our domainname is validated against it. We are now bringing this in-house and want to know the easiest way to move it? It doesn't have many objects, so happy to recreate them but to do so, I need to validate our domain against this Azure AD instance. If I do this, I am concerned it will break the existing which would be a problem as we have users using it. Can you have a single domain validated against two directories (no on-prem integration). Also, is there an easier option? I don't mind users having to reset their password.
No, you cannot have one domain name verified in two Azure AD tenants.
The title of this question indicates a common misunderstanding is at play here: Azure AD tenants are not resources within an Azure subscription. If anything, it's the other way around: an Azure subscription is associated to an Azure AD tenant. Read more on the relationship between an Azure subscription and an Azure AD tenant at "How Azure subscriptions are associated with Azure Active Directory", and on how to transfer Azure subscriptions across Azure AD tenants at "Transferring ownership of an Azure subscription."
If there already exists an Azure AD tenant with your domain name, you should simply take control of the tenant. If you already have access to a user account that is a tenant administrator, then you simply need to evict (demote, disable or delete, depending on your situation) the users from the third party. If you don't, you can ask the third party to make your user an admin. (And if that is not possible either, you can contact support to prove ownership of the domain name.)

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