An administrator adds a new network device to the Cisco ISE configuration to authenticate endpoints to the network. The RADIUS test fails after the administrator configures all of the settings in…

Endpoint profiling occurs after successful RADIUS authentication. If the RADIUS test itself fails, the system hasn't even reached the stage where it can profile an endpoint, so 'unknown' profile status is not the root cause of the test failure.

Endpoint credentials are used for authenticating the end-user or device to the network, which happens *after* the RADIUS communication channel between the network device and ISE is established. A RADIUS test failure implies an issue with the channel itself, not necessarily endpoint credentials.

While certificates are crucial for EAP-based endpoint authentication and secure communication, a basic RADIUS test verifies the shared secret and connectivity. A self-signed certificate typically wouldn't cause a fundamental RADIUS test to fail between the NAD and ISE, unless it's specifically an EAP-TLS or a similar method for the NAD-ISE communication which is less common than the shared secret for this initial test.

The shared secret acts as a password that authenticates the RADIUS client (network device) to the RADIUS server (Cisco ISE). If this secret is not configured identically on both the switch and Cisco ISE, the RADIUS packets cannot be authenticated, leading to a failure in the RADIUS test and preventing any further authentication attempts from succeeding.