FortiGate
FortiGate Next Generation Firewall utilizes purpose-built security processors and threat intelligence security services from FortiGuard labs to deliver top-rated protection and high performance, including encrypted traffic.
kwcheng__FTNT
Article Id 286227
Description This article describes how to replace the IP address in a captive portal or authentication portal with FQDN or domain name.
Scope FortiGate.
Solution

By default, the FortiGate will be using its own IP address for the captive portal page:

 

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To change/hide the IP address to FQDN/domain name, perform the following command:

 

config firewall auth-portal
    set portal-addr "domainname.com:1000"
end

 

Important notes:

Make sure that the client DNS will resolve 'domainname.com' into the FortiGate IP address before inputting the above command:

 

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Test the captive portal again after that and it will be possible to observe that the IP was replaced with the FQDN/domain name.

 

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