No, portal is hosted from AP so you cannot change that but you can use authentication part proxied to SZ. Means authentication request will be sendout from SZ to AD server, rather than APs.
Please note that authentication should work irrespective of proxy or non-proxy, so I would suggest you open a case with support, if you can find a fix by your own.
Regards,
Syamantak Omer
Syamantak Omer
Sr.Staff TSE | CWNA | CCNA | RCWA | RASZA | RICXI
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