Hi Everyone,
I wonder if someone might be able to clarify a few points for me. I am currently working on setting up a hybrid configuration and was looking at my options for hybrid mail flow. I have setup a lab environment in Azure and upon running the HCW I noticed the option to specify multiple public IP's and then later the Org FQDN. Upon completion I noticed the Connector setup in O365 will direct all SMTP traffic to the DNS name specified on the Org FQDN page. My two questions that I am looking for clarification on are:
1. Can we simply have the DNS name in the org FQDN resolve to multiple NAT'd IP's on our internet facing FW in order to provide HA for SMTP traffic in a hybrid configuration? I'm assuming HWLB is another option but I'm trying to avoid that to keep things simple.
2. If the org FQDN is used by EOP for mail flow, what is the significance of specifying the Public IP Addresses? Possibly added to a whitelist on the EOP side?
Many thanks in advance for your help.
Kind Regards
Chris