Wireless Access

I have AirWave setup to host SSID's via RADIUS. There are two Authentication Servers that can be populated with Domain Controller configurations.

My question is if Authentication Server 1 is being used as the main server and if Authentication Server 2 is being used as backup if 1 is unreachable?

Or is both servers are being used at the same time?

I looked around and could not find an answer to this questions.

From the IAP manual: 

You can configure two authentication servers to serve as a primary and backup RADIUS server and enable load balancing between these servers. Load balancing of authentication servers ensures that the authentication load is split across multiple authentication servers and enables the Instant APs to perform load balancing of authentication requests destined to authentication servers such as RADIUS or LDAP.

The load balancing in Instant AP is performed based on outstanding authentication sessions. If there are no outstanding sessions and if the rate of authentication is low, only primary server will be used. The secondary is used only if there are outstanding authentication sessions on the primary server. With this, the load balance can be performed across RADIUS servers of asymmetric capacity without the need to obtain inputs about the server capabilities from the administrators.

https://www.arubanetworks.com/techdocs/Instant_86_WebHelp/Content/instant-ug/authentication/supp-auth-serv.htm?Highlight=auth-server#Dynamic

Thanks for the information.