MX>

1, cotonso-c0mi.mail.protection.outlook.com > 213.199.154.87, 213.199.154.23

100, mail.messaging.microsoft.com >207.46.163.247,207.46.163.215,207.46.163.138

Hi,

I would like find out some information and clarification with above MX record setup

1) Do EOP setup always can add mail.messaging.microsoft.com as secondary MX record?

2) What if on premise Exchange not available, do the EOP retry send for 48 hrs?

3) Are the 2 MX record work the same on resending and retry in the event on premise Exchange not available?

4) Is this a recommended way or best practice?

2. Yes the limit is 48 hours with retries every 15 minutes

Check out this link for the recommended MX config: https://support.office.com/en-us/article/Gather-the-information-you-need-to-create-Office-365-DNS-records-77f90d4a-dc7f-4f09-8972-c1b03ea85a67

Check out the EOP service descriptions for future references: https://technet.microsoft.com/library/exchange-online-protection-service-description.aspx

Hi,

Looking on the recommendation, should I conclude that the mail.messaging.microsoft.com no longer valid after FOPE?

Anyone can share this?

That is the case for the last O365 environment I looked at.