Find logs to tell if SEP 12.1.5 is pulling from web server

I am tapped, I can't find anything in the logs, reports, or monitor. I have setup Auto-upgrade to groups (Upgrade from 12.1.1 to 12.1.5) to pull from a webserver, where is have the invididual .exe files for each group held. When I check the client details is says "Download Successfull file size 0" but the size 725mb. Is there a way to tell if it is working properly?