Martin,
There should be some misunderstanding on the feature.
The EAP Group Mapping will define which certificate will be presented by the RADIUS server based on the Username/NAS-IP/MAC.
The authentication as such will be performed with the info available in the AAA config. No need to play here with the EAP Groups:
You need the EAP Groups if the client is validating the RADIUS certificate.
The purpose is to present a specific RADIUS certificate.
I use the following use case:
I the check the Usernames like "host/computername.private-domain.local" for computer authentication and the via the EAP Group I check the username and I present a RADIUS certificate that was issued by a Root-CA available on the specific computer.
You can request the users to log-in with something like user@private-domain-local.com to ensure that you'll present an acceptable RADIUS certificate for the client.
If non of the EAP Group is matching, the default RADIUS certificate is presented
The default RADIUS is presenting a certificate from a public authority. It is usually a star certificate (for example *.public-domain.com).
I must use this because the BYOD devices do not have any Root CA from private PKI by default.
I upload this certificate in the "RADIUS Server Certificate"
Hope this help.
Mig