HP ProCurve 6400cl Series Access Security Manual page 202

RADIUS Authentication and Accounting
Messages Related to RADIUS Operation
Message
No server(s) responding.
Not legal combination of authentication
methods.
6-62
Meaning
The switch is configured for and attempting RADIUS
authentication, however it is not receiving a response from
a RADIUS server. Ensure that the switch is configured to
access at least one RADIUS server. (Use show radius.) If
you also see the message Can't reach RADIUS
server < x.x.x.x >, try the suggestions listed for
that message.
Indicates an attempt to configure local as both the primary
and secondary authentication methods. If local is the
primary method, then none must be the secondary method.