Hello.
I have some trouble with my hotspot setup, and I am not sure if it is possible to resolve this as I want. But I want to try at least. 
I have one subnet with hotspot setup. I want all web traffic to flow through a Squid proxy (proxy is on different subnet connected to same router), and that works also (when specifying parent proxy in hotspot setup).
BUT, it does not work when the client is configured for explicit proxy. The client is not trying to connect to port 80 to the website, but only through port 3128 to the proxy, so the traffic cannot be redirected to the login-page.
I cannot allow the proxy traffic without login either, as that would allow the clients to bypass the hotspot by using the proxy..
So Iām stuck!
I need to use explicit proxy, as only then I can do https filterning based on the domains visited. In transparent mode I can only see the IP-addresses connected (for https traffic)
So how to use explicit proxy in a hotspot setup?
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EDIT: I think I have solved it myself by using an already builtin feature for this. My proxy port is 3333, and I added that to the existing nat-rules (hs-unauth redirect for port 3128 etc. Just copied that and changed 3128 to 3333.