Confuse the FQDN value on "Specify the FQDN this connector will provide in response to HELLO or EHLO" on Receive Connector and Send Connector

Hi all,

First, please take a look at the mail flow:

Mail server A (Linux server, FQDN: maila.test.com) -- send mails to --- Exchange 2010 (FQDN: ex10.local.com)

So, I create Receive Connector for mail A, and then on the "Specify the FQDN this connector will provide in response to HELLO or EHLO ", will I type the FQDN of Exchange server or Mail A or leave blank?

(normally I understand this is FQDN and for my lab, when I type FQDN of Exchange on this field I can do the mail flow but FQDn of mail A doesn't.)

- And the other question, I actually don't understand the mean of "Specify the FQDN this connector will provide in response to HELLO or EHLO " field and when we use it ?

And same as for Send Connector.

Please help me understand this field clearly, and it's better you can give me more examples.

Thanks,

cuocdoi.