Somebody asked me today about pointing MDT to a WSUS server (which is best practice really). Do you really want 50+ machines all pulling updates from the outside at the same time? Yeah, I didn’t think so.
Turns out doing so is a very simple tweak in the customsettings.ini file.
Replace MDT01 with the name of your WSUS server. You could use IP, but you’d have to update MDT if that ever changed. Save yourself the hassle and just use hostname.
I’ve also seen it where you need the port of the WSUS server in the ini file. But depending on your WSUS server, you prolly wont need that, just a heads up.