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I've just installed freeradius and start it with a /etc/init.d/ startup script. After I run netstat -nat I dont see that any process is listening on ports 1812 and 1813. I'm using Ubuntu 10.04 LTS and default freeradius configuration. I've tried to manualy edit conf file and to set listening ip addresses and ports, but nothing is changed. I have openbsd-inetd installed but it's turned off. Where could be problem?

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up vote 1 down vote accepted

RADIUS uses UDP and not TCP. The -t in the netstat command tells it to list TCP ports. Try using lsof instead of netstat to examine UDP ports.

You may also need to restart the RADIUS daemon after changing the config file. You can also use tcpdump to actually see what's going across the wire.

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You are right, UDP ports 1812, 1813 are opened. But when I try radtest testing password 0 testing123, I see that client (localhost) is sending requests, but server (localhost, also) is not receiving it (debbuging with radiusd -X). when I try radtest testing password localhost 0 testing123, i get "radclient: socket: cannot initialize udpfromto: Function not implemented" – Boban P. Nov 1 '11 at 12:32
Try using it's real IP address instead of – jftuga Nov 1 '11 at 12:40
It's the same as using In my /etc/hosts/ file, i have a line " localhost radius" (radius is my hostname) because if I delete radius word, I have an error "radclient:: Failed to find IP address for radius". I've tried to add a line " raidus" in the file, but nothin is changed. – Boban P. Nov 1 '11 at 12:49
Solved. I had to uncomment "interface eth0" line in listen section of the config file. Thanks, anyway – Boban P. Nov 2 '11 at 12:56
Actually that's incorrect, RADIUS uses both UDP and TCP. For both RADIUS accounting and authentication over TCP it's port 1812. – Arran Cudbard-Bell May 9 '14 at 18:08

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