Does anyone know if it is possible to configure pam to require both radius AND ssh-key to successfully authenticate ?
The SSH key check is done by
sshd itself before calling PAM. And while the SSHv2 protocol itself allows multiple authentication methods, most SSH daemons do not support requiring more then one.
However, if you have OpenSSH 6.2 or newer, you can use the new
AuthenticationMethods option to require
publickey and one of
keyboard-interactive to succeed:
AuthenticationMethods publickey,password publickey,keyboard-interactive