[Support Policy] Sharepoint supportability of Read only Domain controllers
https://support.microsoft.com/kb/970612/en-us
People picker is unable to resolve users in a trusted forest if the only domain controller SharePoint can access is read-only.
https://support.microsoft.com/kb/970612/en-us
People picker is unable to resolve users in a trusted forest if the only domain controller SharePoint can access is read-only.