We have 2 identical radius servers (FreeRADIUS 3.0.21) On the same servers radsecproxies are running. (radsecproxy 1.8.2) The servers have 2 IP adresses (1 as secondary which should be used for radius and radsecproxy). After freeradius restart everything works fine. Freeradius sends server status packets to the internal radsecproxy and to external radius servers (eduroam) with the correct source (secondary ip address). It works for a long time but suddenly one of these freeradius sends the server status packets with a wrong source ip (primary) to the internal radsecproxy. Radsecproxy ignores these packets of course. We followed the instructions in FAQ ("Is there a way to bind FreeRADIUS to a specific IP address?") Any ideas how to trace / correct this? thanks Stefan Here are the configuration details: ### Server Network Config $ ip address ... 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000 link/ether 00:50:56:82:9b:a3 brd ff:ff:ff:ff:ff:ff inet 10.173.120.23/23 brd 10.173.121.255 scope global eth0 valid_lft forever preferred_lft forever inet 10.173.120.11/23 brd 10.173.121.255 scope global secondary eth0 valid_lft forever preferred_lft forever ### site default server default { listen { type = auth ipaddr = 10.173.120.11 port = 1812 ... } ### proxy.conf home_server RadSecProxy { type = auth ipaddr = 10.173.120.11 port = 11812 status_check = status-server check_interval = 30 check_timeout = 4 num_answers_to_alive = 3 ... } ### RadSecProxy Log ... # successful server status from/to corresponding radius Aug 9 08:28:19 2021: replyh: got status server response from tld2.eduroam.de Aug 9 08:28:22 2021: replyh: got status server response from tld1.eduroam.de Aug 9 08:28:22 2021: Access-Accept (response to Status-Server) from _self_ to tld1.eduroam.de (193.174.75.134) Aug 9 08:28:22 2021: Access-Accept (response to Status-Server) from _self_ to tld3.eduroam.de (194.95.245.98) Aug 9 08:28:30 2021: Access-Accept (response to Status-Server) from _self_ to tld2.eduroam.de (193.174.75.138) # successful server status from/to local radsecproxy Aug 9 08:28:37 2021: replyh: got status server response from radius-local # suddenly wrong source ip in server status packet freeradius-to-radsecproxy Aug 9 08:28:47 2021: radudpget: got packet from wrong or unknown UDP peer 10.173.120.23, ignoring