Steps for creating GMSA
  1.  Open PS ISE as Administrator run >Add-KdsRootKey -EffectiveTime((get-date).AddHours(-10)) this will output a Guid this will generate a new root key in the Active Directory.
  2. Create a new ADservice account using New-ADServiceAccount [GMSAName] -DNSHostName [adfs.idynamics.com] -ServicePrincipalNames http:/[adfs.idynamics.com]
  3. Set SPN using setspn -s host/adfs.idynamics.com [idynamics]\[GMSAName]$