Service Principal Name is effectively a service account within Azure.

Required in this scenario for our Terraform Provider function to connect our TF code to our Azure Subscription.

1. Login to https://portal.azure.com.
2. Click into Azure Active Directory.
3. Click App Registrations >+ New registration.
4. 
5. Provide a name for your SPN ie. terraform-spn, provide any valid URL within Redirect URI.
6. Click Register.
7. 
8. We require 4x details of information in order to use Terraform;
   1. client_id; This is Azure Application ID.
   2. client_secret; This is our SPN’s client secret key which we generate within Azure.
   3. tenant_id; This is Azure AD’s directory ID.
   4. subscription_id; This is our Azure Subscription ID.
9. Application ID from our newly created SPN. In Terraform, this is client_id variable.
10. 
11. Within our SPN blade, click Certificates & secrets > + New client secret.
12. 
13. Provide a name and duration for secret. Click Add.
14. 
15. Copy our newly created client secret string. In Terraform, this is client_secret variable.
16. 
17. Click into Azure Active Directory > Properties.
18. Copy the Directory ID string. In Terraform, this is tenant_id variable.
19. 
20. Now go into Subscriptions > Overview and copy the Subscription ID. In Terraform, this is the subscription_id variable.
21. 
22. Within Subscriptions > [Your Subscription] > Access control (IAM) > + Add > Add role assignment.
23. Role: Contributor.
24. Select our newly created SPN ie. terraform-spn and click Save.
25. 

 

Congratulations, we have now successfully configured an Azure SPN ready for use with Terraform!