We are a mid-size organization and in the early stages of rolling out M365 E5 for data management. One thing we are desirous of is to be able to place a virtual Fortinet firewall in Azure to standardize how we protect our tenant with how we protect our on-prem network. Since we are talking about data management as well as making M365 our campus wide collaboration tool we could be talking about a considerable amount of data each month passing through the firewall.
My question is regarding Azure egress data charges. Does Azure meter every bit of data that passes back out of the virtual appliance and charges that as egress data even though it is exclusively O365 data? Any comments with experience doing this or answers to this question would be greatly appreciated.