Hello
We are in the process of evaluating the Cisco ISE VMWare appliance with a view to replace our existing FreeRADIUS installation as authentication provider for our wireless network and VPN service. As a part of this we are hoping to migrate our user authentication to Microsoft Active Directory - we have previously authenticated against a different identity store (not MS AD). Because of this legacy our Windows domain is not the same as our RADIUS realm name - the Windows domain is "win.mydomain" whereas we wish to allow users to authenticate using "username@mydomain" or even "username@student.mydomain" as they are doing today. We are experiencing an issue where authentication requests with the format "username@win.mydomain" will be forwarded to the Windows AD whereas authentication requests with the format "username@mydomain" will fail with the log message "User not found in Active Directory". We do not know if the ISE itself is validating the username and triggering this error, or if the error originates from AD. We suspect the that the ISE is not even asking AD because "win.mydomain" is the domain configured in "Active Directory" in "External Identity Sources".
Authentication requests against the AD without a realm are successful (that is, using only "username"). With this in mind we located a post on the Cisco support forums that described a process of proxying the request back to the ISE and strip the realm information, but this was specific for the ACS platform. We have attempted to implement this solution but it is still not working as we would have hoped, and we are not entirely certain where the fault might lie. We are currently using PEAP with MSCHAPv2 for authentication in our WLAN where the main problem is. We suspect that the "proxy-to-self" with realm stripping is an issue with PEAP.
Is there a supported method of achieving our goal, or should we abandon the ISE platform as our scenario is simply not supported?
