Switch Between Active Directory and LDAP Using the GUI
When you switch from Active Directory to LDAP or vice versa, all the users who belong to the domain that was being used will no longer be able to access the array unless they are in the new domain. For users who are already logged in to the array, any new operation will result in an error.
Even if a user is part of both domains, the login requirements might be different. For example, the username for an LDAP authorized user takes the format <username>@domain_name> where domain_name is the value you entered when you created the LDAP configuration.
Regardless of which service you are using, local account access is still permitted.