To enable the debugging for LDAP, follow the below steps: 

1. Navigate to [TDV_Server_Dir]/conf/server open log4j2.properties file in an editor and add the below lines at the end. 

##LDAP###

logger.security.name=com.compositesw.server.security
logger.security.level=DEBUG

logger.DefaultDomainManager.name=com.compositesw.server.security.DefaultDomainManager
logger.DefaultDomainManager.level=DEBUG

logger.DomainManager.name=com.compositesw.server.security.DomainManager
logger.DomainManager.level=DEBUG

logger.LdapUtils.name=com.compositesw.server.security.LdapUtils
logger.LdapUtils.level=DEBUG

logger.LdapExternalDomain.name=com.compositesw.server.security.LdapExternalDomain
logger.LdapExternalDomain.level=DEBUG

logger.AuthenticationManager.name=com.compositesw.server.security.AuthenticationManager
logger.AuthenticationManager.level=DEBUG

2. To activate the debug trace, you should restart the TDV Server. However, if you prefer not to restart it, you can use an alternative approach:

• Navigate to Studio > Administration > Configuration > Server > Configuration > Debugging > Debug Output Enabled.
• Change the value to “True”.
• Click “Apply” but don’t close the window.
• Immediately change the value back to “False”.
• Click “Apply” and close the window.

NOTE: These flags don't exist in log4j2 properties, you will need to append them to the end of the file.