I am trying to configure Parallels RAS through Fortiweb. It works find if I login through web browser but it does not work through client. When I checked the traffic on fortiweb, it shows destination 0.0.0.0 and method others. For successful traffic through web it shows method get with correct destination server.
Hello first question: why? what would be the goal of put a VDI scheme behind a WAF?
Remember that FortiWeb is a web application firewall, focused by design in HTTP/HTTPS (and FTP) traffic. Under more popular deployment mode, (reverse proxy), the default action is drop non-http/https/ftp traffic. It only deals with web traffic.
If you want to try and proxy emulation traffic (as rdp under your vdi arq), consider another modes of operation or configure bypass non-web traffic in your Fortiweb
The reason putting behind fortiweb, is the server address we use also give access through web. As you suggested, created bypass rule for non-https traffic will be best option as it will allow client traffic and filter web traffic for the same address.
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