802.1x with GoDaddy Certificates EAP-TTLS

[Torsten Wilms]

I have a little question. I am not sure but does clients need to resolve AAA Server via DNS and need to reach AAA Server if I use EAP-TTLS with GoDaddy x509 Certificates to verify the certificate on e.g. Mobile Devices or does the client need in any other case to reach some endpoint to validate the certificates common name?
I have a AAA Server in a separate Network installed which is only reachable for the authenticator (Wireless Controller). The Clients communicate with the AccessPoint. A hand full devices like Android are not able to connect the wireless because of certificate validation error. The other devices has no problems. You see the certificate of the server and after accept, the connection will be established. The AAA Server sends the full chain like RootCA, Intermediate and server certificate.
BR. Torsten