Service Principals and realtime use cases

[Suresh_Godaba]

Hi All,

looking for simple explanation for service principals for better understanding and reals use cases in my subscription.

Please provide your suggestions for the same.

[#2 · Accepted solution]

If you are familiar with service account in active directory may be it can help to better understand .
Service principal like service account is used to avoid putting user credentials in a deployment or an install .
If you want to deploy a Service that need domain admin or whatever role in AD you will use  a service account instead of a user one . 
The same apply in Azure if you want to deploy something in an automated fashionn you should not pick a user identity . You should  create a service principal or use an existing  that will facilitate authentication to other services .Then you can apply a least privilege strategy . Also service principal are a common way to authenticate for automation tools like Terraform or Azure DevOps or some others services like Azure Kubernetes Service .
You can authenticate as SP with Password or Certificate .

[#3]

@Suresh_Godaba 

Worth to take a look at this:

https://learn.microsoft.com/en-us/azure/active-directory/develop/app-objects-and-service-principals

[#4]

Hi @Suresh_Godaba
Service Principals are security identities in Azure Active Directory (AAD) that are used to represent applications or services that need to access resources within your Azure subscription. They allow you to define permissions and roles for your applications, enabling them to interact with other Azure services securely and without the need for user intervention.

Here are some real-time use cases for Service Principals:

1- Application authentication: You have a web application that needs to access Azure resources like storage accounts, databases, or other services. You can create a Service Principal for the application and grant it the necessary permissions. This way, the application can securely access the resources without the need for user credentials.

2- Automation and DevOps: When creating scripts or using tools like Azure PowerShell, Azure CLI, or Azure DevOps pipelines, you may need to interact with Azure resources. By creating a Service Principal, you can authenticate these automation tools without using individual user accounts, reducing the risk associated with sharing user credentials.

3- Managed identities for Azure resources: Some Azure resources, such as Azure Functions or Azure VMs, can have managed identities assigned to them. These managed identities are a type of Service Principal that automatically manage the lifecycle of the identity, such as creating, updating, and deleting the Service Principal. This simplifies authentication and access management for those resources.

4- Multi-tenant applications: When building a multi-tenant application, you may need to access resources from different Azure subscriptions or directories. Service Principals can be used to represent your application in each tenant, allowing it to access resources across tenants while keeping permissions separate and secure.

5- Delegated access to resources: In some scenarios, you may want to grant third-party applications or services access to specific resources within your subscription. Service Principals can be used to create dedicated identities for these external services, allowing them to interact with your resources with a defined set of permissions.

To better understand Service Principals in your subscription, consider the following suggestions:

Review the applications and services you have deployed in your subscription and identify which ones need to access Azure resources.
Determine the appropriate permissions and roles required for each application or service.
Create Service Principals for each application or service and assign the necessary permissions and roles.
Regularly audit the Service Principals in your subscription to ensure that they have the correct permissions and roles, and update them as needed.

By following these suggestions, you can effectively manage access to your Azure resources using Service Principals and ensure a secure and well-organized subscription.

[#5]

@Suresh_Godaba 

Here may also help, as well as managed identity in case you are interest:

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