Merge pull request #7628 from braze-inc/bd-3228

BD-3228 Delegating your custom domain

_docs/_hidden/private_betas/link_shortening.md

@@ -124,6 +124,21 @@ Contact your Braze account manager if you're interested in getting started with
   - You can also use unique subdomains, such as `sms.braze.com`.
 - We recommend choosing a domain with as few characters as possible to minimize the length of your URLs.
 
+#### Delegating your custom domain
+
+When you delegate your domain to Braze, we automatically handle the certificate renewal to prevent a lapse in service. 
+
+To delegate your domain to Braze, do the following: 
+
+1. Bring a domain that meets the above requirements to your customer success manager. Braze will then check the existing DNS configuration for the domain and confirm that:
+- No CAA records exist OR
+- CAA records *do* exist but have a record for {% raw %}`<any number> issue "letsencrypt.org"`{% endraw %} or {% raw %}`<anynumber> issuewild "letsencrypt.org"`{% endraw %}
+2. Create four new A records, one for each IP, and confirm that they are the only A records that exist for the domain link host:
+- 151.101.130.133
+- 151.101.194.133
+- 151.101.2.133
+- 151.101.66.133
+
 ### Using custom domains
 
 Once configured, custom domains can be assigned to one or multiple SMS subscription groups.