My NTop Readings

Good day to all
maybe some one can shad some light on the ntop reading and understanding for me,

  1. Is there any traffic that can go through my Red Nic and not show on ntop?
  2. What is the traffic that is going through my server (circled in red on the attached picture)? is that the server downloading or looking for something in the net?
  3. what is the grayed out number 2 (circled in blue) on my server name?

Please find the doc in the link below :
https://github.com/ntop/ntopng/blob/dev/doc/UserGuide.pdf

Grayed 2 mean number of Virtual hosts.
Press on ip address of your server and you will see HTTP(2) in detailed host page