hi, we use nagios to monitor our freeradius install. this is using the adv_radius_check plugin to check from the nagios servers a user on the freeradius server (in the users file), the following are the succinct details users file entry nagios-user Huntgroup-Name == "nagios", Cleartext-Password := "password", Autz-Type := nagios-check Reply-Message = "This server is active", Fall-Through = No huntgroup file nagios Client-IP-Address == 127.0.0.1 nagios Client-IP-Address == 10.1.1.2 nagios Client-IP-Address == 10.1.1.3 sites-enabled/default auth entry authorize { Autz-Type nagios-check { files ok = return } } okay. so the user authentication tests fine with radtest on the radius server....and it works fine from the 2 nagios boxes...almost always. occasionally we see the following error come through during the 5-minute interval tests....... Wed Nov 7 11:21:40 2007 : Auth: Login OK: [nagios-user] (from client 10.1.1.2 port 0) Wed Nov 7 11:26:40 2007 : Auth: Login incorrect: [nagios-user] (from client 10.1.1.2 port 0) Wed Nov 7 11:29:40 2007 : Auth: Login OK: [nagios-user] (from client 10.1.1.2 port 0) of course, when that 11:26:40 event occurred, nagios claims a problem with the RADIUS. now, the check method is the same, the password is the same, the IP is the same, in essence nothing changes at all between each 5-minute test (the last entry 11:29:40 is quicker than a 5 minute interval as nagios catches up with failed events within a following window) and this is just plain PAP check in users file. so why is it occasionally failing? has anyone else seen this sort of activity? alan