Every time we make changes to our backend that requires changes to our clients DNS setup, we have to go through a lengthy process with emails, phone calls, email reminders, and so one in order to get each one to implement necessary changes.
In order to simplify this once and for all I've done the following: I've set up a Google Cloud project with a Cloud DNS zone for dns.ourdomain.com
This way I can instruct our clients to set up:
www.client.com CNAME client.dns.ourdomain.com
And in the Cloud DNS console we add:
client.dns.ourdomain.com CNAME client.backendserver.com
Now in the future if we need to do changes we can do it all in one bulk operation without ever involving the clients.
I have tested this setup and it's working just fine, but there seems to be a consensus that this is bad practice. If any, what are the potential pitfalls?