Hello
I am running Exchange 2013 CU10 on-prem. I have 5 CA servers and 5 MBX servers. Currently we send all email from on-prem through EOP, and EOP accepts all smtp email for our accepted domains, and then forwards the email down to our on-prem servers. Currently we have 5 unique NAT rules from EOP to our on-prem CAS servers. Example. When running the hybrid config wizard one of the things the wizard asks for is the FQDN name for mail from O365 to on-prem. Example "smtp.mydomain.com". As I mentioned before, I am using individual NAT for mail from EOP to on-prem. If I want to continue using the existing NAT rules that I currently have, would I need to create 5 external DNS records for "smtp.mydomain.com" that map to the external IP address for each NAT rule? Is this a preferred solution vs. using a load balancer between EOP and on-prem for hybrid mail flow?
Example
"smtp.mydomain.com" maps to 12.5.6.2
"smtp.mydomain.com" maps to 12.5.6.1
NAT rule 1 EOP----->12.5.6.2---->NAT----->onpremCAS1
NAT rule 2 EOP----->12.5.6.1----->NAT------>onpremCAS2
ect
ect
Bulls on Parade