Forum Discussion
Securing mailflow in the hybrid configuration
Not sure what you mean here, the outbound connector will be used to redirect *any* messages received for mailboxes still hosted on-prem. This includes both internal mail, sent from O365 mailboxes in the same tenant, and external mail, sent from other O365 tenants or internet users.
Where is your MX pointing at?
Here's the picture.
I'm talking about the red line which shows the SMTP between EO and on-prem. Basicaly We need to set up the receive connector on the Edge servers to not accepts emails from any other tenant exepct our. Is that clear?
If your MX is pointing to on-prem, internet senders and O365 users outside of your tenant will not be hitting the connector. Generally speaking, you can restrict the connector to only specific domain, or even scope it based on a transport rule (for example with the "sender is internal" condition), but it should not be needed in your scenario.
