Hi,
I hope below url will helpfull for you
https://community.arubanetworks.com/t5/Security/NEW-TechNote-CPPM-amp-Juniper-SRX/td-p/263505
You need to add Juniper SRX as context server and then you need to enforce session notify enforcement (JUniper srx IP) profile to captive portal authenticated users. Clearpass will send notification to Juniper SRX about client device ip address, User Name, User Role, Domain, Device Type, Machine OS.
Regards,
Milind Y