To test the RADIUS server directly, execute inside the VM:
sudo radtest user1 testpwd localhost 18128 testing123
mysql -u root -psecret radius
SELECT id, username, attribute, value, op FROM radcheck WHERE username = 'user1' ORDER BY id;
...
INSERT INTO radpostauth (username, pass, reply, authdate) VALUES ( 'user1','testpwd','Access-Accept', '2018-01-26 22:07:14');
Create an user with daloRadius
SELECT id, username, attribute, value, op FROM radcheck ORDER BY id;
...