[NEBULA] What is site usage means in Overview page? How do you calculate it?

Hey BackZero, glad to see you around here again.
That usage indicator shows the amount of data consumed by the clients of the site, within the last 24 hrs.
If you have 10 or less devices in your site, you will be able to get the same value if you sum-up the usage of each device in Site-Wide > Summary report > Top devices by Usage (it's a top 10).

If you have time, you can take a look to Documents > Nebula Solution > Nebula Solution Documentation > 6. Nebula Control Center User's guide and in chapter 6, page 117 you will find some details about the overview page.

Hey @BackZero ,
The number of clients in Overview page shows the total clients that the site has, including the NAP, NSW and NSG clients. In the most typical and simple topology scenario, the connection will be Inet > NSG > NSW > NAP meaning that the NSG will have the same clients of NAP and NSW (including them), having this as the total clients of the site.

In your case, could you please provide the topology? It seems like you have a different topology than the described above