Good morning, i'm searching ways to delete the security warning in the hotspot because we need to create an hotspot network for a building.
I know that the client have to add CA certificate, but the problem is before, without an redirect the client cannot go on the hotspot login page.

Which security warning are you talking about?

https warning? most os's use the unsecured path http to detect if a redirect is being done and present then the login page.

Redirect of https without warning is not possible.

https warning? most os's use the unsecured path http to detect if a redirect is being done and present then the login page.

Redirect of https without warning is not possible.

You should use the Captive-Portal DHCP/RA option (DHCPv4 Code: 160 | DHCPv6 Code: 103)

For more information read the corresponding RFC 7710.