What is the hostname of my Office 365 MX records?

The MX record that is created for our domain name is based on a predefined naming conversation.

The Office 365 MX records consist of two parts:

1. The “static” part

Office 365 uses the same static suffix for all the domain names
hosted at Office 365 – mail.protection.outlook.com

2. The dedicated part

This section is created for a particular public domain name which was registered.

The naming convention based on the following structure.

Organization name, the hyphen characters and the domain name suffix.

To be able to demonstrate this naming structure, let’s use the domain name – o365info.com

In the following diagram, we can see that process in which Office 365 creates a dedicated MX record for the public domain name – o365info.com

The “result” results” is the host name – o365info-com.mail.protection.outlook.com which includes the “dedicated part” (o365info.com ) + the “shared path” that is identical for every Office 365 tenants (mail.protection.outlook.com)

Office 365 MX record structure

How to get the value of our MX record from the Office 365 portal

The information about the value of the “Office 365 MX record” that represents our domain name appears in the Office 365 portal.

To be able to get this information we will need to login to Office 365 portal using Global administrator credentials.

What is my Office 365 MX record-01

Select the domain name which you want to view his DNS settings

  • In our example, we select the registered domain name – o365info.com
  • In the setting window that appears, select the menu – DNS settings
What is my Office 365 MX record-02
  • Click on the Exchange Online section
What is my Office 365 MX record-03

In the following screenshot, we can see the information about the DNS records

We want to know what is the value of the MX record that Office 365 creates for our publicly registered domain name.

In our example, the value of the MX record is – o365info-com.mail.protection.outlook.com

What is my Office 365 MX record-04