> Nmap? Why scan ports when you can simply eg 'netstat -an | grep 1812' Lack of thinking on my part? No offense taken; my way was definitely roundabout.
Anyhow, after killall & restart, this is kind of odd: # netstat -anp | grep 1812 udp 0 0 0.0.0.0:1812 0.0.0.0:* 20883/radiusd And since I'm using 0 for the port setting: # grep 1812 /etc/services radius 1812/tcp # Radius radius 1812/udp # Radius It looks like radius is opening UDP 1812 (and 1813) but not the corresponding TCP ports anymore and that's why I suddenly can't connect to it - unless I'm misreading the services file and radiusd uses strictly UDP. - List info/subscribe/unsubscribe? See http://www.freeradius.org/list/users.html