Non-AD DNS question!
We're having trouble accessing (http://)spring.io and we've narrowed it down to being the way the domain is set up and the Windows DNS service. It's got a CNAME setup for the root, pointing at a host on another domain (spring.io CNAME= cf-ssl40915-protected.spring.io), but when attempting to access or even resolve the site via a Windows DNS host, we get nothing - the CNAME is not returned. When accessing/resolving via a Linux BIND host, the CNAME is returned and the site can be accessed.
Can anyone explain what's happening? Is there anything further we can do to test/diagnose this?