Symptom
-- after boot of c3650, incorrect NAS-IP-Address is used
-- in RADIUS debugs after boot we see Config NAS IP: 0.0.0.0 and switch will pick the best (lowest) IP address from Loopbacks (not configured radius source interface, that is GigabitEthernet1/0/48 with 10.48.44.69):
*Jul 28 08:19:28.582: RADIUS/ENCODE(00000FAD):Orig. component type = CTS
*Jul 28 08:19:28.582: RADIUS(00000FAD): Config NAS IP: 0.0.0.0
*Jul 28 08:19:28.582: RADIUS(00000FAD): Config NAS IPv6: ::
*Jul 28 08:19:28.582: RADIUS/ENCODE(00000FAD): acct_session_id: 4003
*Jul 28 08:19:28.582: RADIUS(00000FAD): sending
*Jul 28 08:19:28.586: RADIUS/ENCODE: Best Local IP-Address 10.11.254.89 for Radius-Server 10.48.17.156
*Jul 28 08:19:28.586: RADIUS(00000FAC): Send Access-Request to 10.48.17.156:1812 id 1645/1, len 135
*Jul 28 08:19:28.586: RADIUS: authenticator AA 9F 53 8B 0A C7 BF F1 - 77 A2 38 96 FA 36 3A AA
*Jul 28 08:19:28.586: RADIUS: User-Name [1] 14 "#CTSREQUEST#"
*Jul 28 08:19:28.586: RADIUS: User-Password [2] 18 *
*Jul 28 08:19:28.586: RADIUS: Vendor, Cisco [26] 34
*Jul 28 08:19:28.586: RADIUS: Cisco AVpair [1] 28 "cts-rbacl-source-list=0000"
*Jul 28 08:19:28.586: RADIUS: Vendor, Cisco [26] 37
*Jul 28 08:19:28.586: RADIUS: Cisco AVpair [1] 31 "cts-device-capability=monitor"
*Jul 28 08:19:28.586: RADIUS: Service-Type [6] 6 Outbound [5]
*Jul 28 08:19:28.586: RADIUS: NAS-IP-Address [4] 6 10.11.254.89
*Jul 28 08:19:28.587: RADIUS(00000FAC): Sending a IPv4 Radius Packet
