Pre-Requisites for SMS Authentication Setup

For us to do the deployment of the SMS feature, we would need some pre-requisites to be completed.

1. Create a sub-domain you would like the Users receiving SMS be registered with. An example would be user@sms.mydomain.com, where sms is the subdomain.
   1. Note: If the root domain is verified in your Azure AD, users will not be able to login. Please refer to Login error from Microsoft about Incorrect Username
2. Create a Twilio Account, buy a phone number, and get the Phone Number, Account SID, and Auth Token ready
3. Create a SendGrid Account, and Authenticate your sub-domain

Twilio

1. Create an account with Twilio (https://www.twilio.com/)
2. You may need to select SMS as a service
   
3. Purchase a Twilio phone number capable of sending SMS
4. Keep a note of the Phone Number, Account SID, and Auth Token for later use
   

SendGrid

1. Create an account with SendGrid (https://sendgrid.com/)
2. Authenticate your sub-domain in Sender Authentication page. This will need some DNS entries including CName, TXT, and MX Records.
   1. Assign the MX record a priority of 10, and point it to the address: mx.sendgrid.net. If there is no field for priority, type 10 before the address. e.g. 10 mx.sendgrid.net. Please refer to SendGrid article.
      

We would need the following information from you:

1. Please let us know the subdomain you would like the Users receiving SMS be registered with? An example would be user@sms.mydomain.com, where sms is the subdomain. Email sent to any address in the receiving domain or subdomain will be triggering the SMS One Time Passcode process.
2. What action would you want EUM to take if it faces a Error while processing, say due to missing Mobile Number for the user, or Missing User?

Note: New User Creation or User Registration need to capture the mobile number of the user for the SMS Authentication to work.

What is a subdomain? Please refer to this article: What is a subdomain? | Domains - GoDaddy Help CA

How to find out my Domain Host to enter DNS: Please refer to this article: Finding your domain host  |  Cloud Identity  |  Google Cloud