This daemon listens for RADIUS packets on a well known
UNIX domain socket. When a packet is received, it queries
LDAP to see if the user is configured for RADIUS authentication.
If so, then the packet is forwarded to the 3rd party RADIUS server.
Otherwise, a bind is attempted against the LDAP server.
https://fedorahosted.org/freeipa/ticket/3366http://freeipa.org/page/V3/OTP