You can specify a certain Advanced Authentication server on a workstation that can be used when a workstation is joined to a domain, but user wants to force connection to a specific Advanced Authentication server and when a workstation with Mac OS X Client is not joined to a domain.
In the /Library/Security/SecurityAgentPlugins/aucore_login.bundle/Contents/etc/aucore_login.conf file, configure discovery.host = <IP_address|domain_name>.
For example, discovery.host = 192.168.20.40 or discovery host = auth2.mycompany.local.
You can specify a port number (optional parameter) for the client-server interaction: discovery.port = <portnumber>.
NOTE:For Mac OS logon event, select the OS Logon (local) Event type if you want to use Mac OS X Client on non-domain joined workstations.