HI there,

Are your sure that your freeradius server is up? Try to start freeradius in debug mode and make the radtest again:

sudo freeradius -X
radtest bob bob localhost 1812 testing

If you get an error trying to start the server with "sudo freeradius -X" try to stop it and start+test again:

killall freeradius
sudo freeradius -X
radtest bob bob localhost 1812 testing

As James said you need to run in debug mode while tetsing...so you can check whats going on.

Cheers,

Shirkavand