3: I think this is a nice write-up:
https://www.flomain.de/2016/12/aruba-instant-with-external-captive-portal/ with the exception that you need to install an SSL server certificate on your Instant AP in order to fix the certificate warnings. If you have Aruba Central management, you can use the aruba_default certificate from there, otherwise you need to install your own certificate. If you have Aruba Central management, there is Cloud Guest in there as well, and you could use that as well.
1&2: Yes, create an account in the Instant local users with a username and password of your choice and the type of Guest.
You will need to change the URL from
https://securelogin.arubanetworks.com/cgi-bin/login to your own domain that you requested the certificate on, like
https://guest.your-own-domain.tld/cgi-bin/login------------------------------
Herman Robers
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If you have urgent issues, always contact your Aruba partner, distributor, or Aruba TAC Support. Check
https://www.arubanetworks.com/support-services/contact-support/ for how to contact Aruba TAC. Any opinions expressed here are solely my own and not necessarily that of Hewlett Packard Enterprise or Aruba Networks.
In case your problem is solved, please invest the time to post a follow-up with the information on how you solved it. Others can benefit from that.
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