Create an Azure Service Account with PowerShell

Dear all !

Well, actually, there is no term „Azure Service Account“ in Microsoft Azure, it is called an App with a Service Principal. So whenever you want to access Azure Resources programmatically, (i.e. via REST), you probably do not want to use a persons Usernam/Password combination, you want to use a GUID, dedicated for a particulat reason.

This App, then only has access the the resources you want, so you can fine-grane security very easily. You can do this in the Azure Portal, as described here:

If you do need to do this more often, Powershell is probably the better way.

STEP 1: Set your Azure tenant

So you see we use the AzureAD module in version or higher, which should be installed on your system. The module is available on the PowerShell Gallery, so a simple „Install-Module AzureAD“ in a PowerShell Session with administrative rights should work.

Step 2: Authenticate to your tenant

Tipp: The Connect-AzureAD commandlet will ask you for credentials, nevertheless if you are logged in already with Login-AzureRMAccount

If we look into our Azure portal ==> Azure Active Directory ==> App registration its pretty empty here.

Step 3: Define the AppID settings

Some notes on the code above. Our AppID´s Name is PSAppID. You need to set a URI and also a reply URI, otherwise the creation of the Service principal in the next step will not work.

Tipp: It does not matter if the websites if $appURI, $appHomepage, $appReplyURL really exist, they just need to be filled with reasonable values and $appURI and $AppHomepageURL MUST NOT be identical.

After defining the variables, the script checks if the App is already available, and if not creates it.

Step 4: Create the Service Principal

This command now finally creates the „Service Account“, which is in Azure Terms the Service Principal.

Tipp: Without this step yuo are not able to create an AppKey (= Password) to use this AppID to authenticate to Azure.

Lets look into the Portal, what we created so far:

Step 5: Create a Password (AppKey) for the new AppID

Each AppKey has a lifetime in years, and there is also an unlimited option. In our example below we generate a Key with a 1 year lifetime.

Tipp: Store the AppKey which resides in $appKey.Value in a secure place and DO IT NOW! The AppKey will not be safed anywhere else and is gone after you close the PS Session.

Thats it – Now you have an AppID/AppKey, just done with PowerShell!