I have an environment in which ArcGIS Server and Portal have been federated at the 10.4 version. I am working with the log files within ArcGIS Server to capture some usage statistics. The log files are reporting the information I am seeking at a "verbose" level with the exception of the user which always reports "Anonymous".
I have changed the settings to not allow anonymous in several locations including the IIS that is hosting my portal and arcgisserver environment and the 'allow anonymous' within Portal. The web adaptor has been configured for portal to handle security of the ArcGIS Server. Active Directory is operating and I am able to capture username information from IIS which leads me to believe there is something in the configuration of a the federated environment that is causing the "anonymous" to be displayed. From the reading I have done I see several posts discussing 'named users' for the portal environment however with active directory being enabled I had hoped that the calls to ArcGIS Server would be still display the user logged name of the person who makes the request to ArcGIS server. My users are in the active directory but will never be "named users" within the portal environment.
The environment is fully functional and I do not have any problems other than the "anonymous" or "anonymous user" in the user name of the log files. Does anyone have any insight on this or have you experienced any similar issues with the "anonymous" users in ArcGIS Server logs?