Thread:Extension talk:LDAP Authentication/search multiple OUs (Active Directory)/reply

The extension allows for multiple domains to be configured, which is why most configuration options are arrays. The options that are not arrays apply to all domains. Some configuration options allow multiple values per domain, but SearchStrings does not.

If you are using OUs as domains, you can configure multiple domains in the extension. Otherwise, this configuration isn't necessarily supported.

I'd recommend using group restriction, if that is a possibility.