title: Modify or create user with custom OnPremisesSecurityIdentifier in Azure Active Directory
body: <p>We are trying to create users with <code>OnPremisesSecurityIdentifier</code> attribute but without AD Connect. I mean by using Azure api, Microsoft api or PowerShell
  Since now we couldn't do it because it is an only read attribute.
  But then, if it is only readable, it means that only AD Connect can set it?</p>
  
  <p>Since now we have tried <code>New-AzureADUser</code> and <code>Set-MsolUser</code> in PowerShell, and use it api graph: Microsoft and Azure. But none of them make the magic.</p>
  
  <p><a href="https://docs.microsoft.com/en-us/graph/api/resources/user?view=graph-rest-1.0" rel="nofollow noreferrer">Here is pretty clear that is not writable</a>, but AD Connect can do it, so there has to be a way...</p>