Chapter 23 WAN Optimization, Web Cache, Explicit Proxy, and WCCP : The FortiGate explicit web proxy : Proxy chaining (web proxy forwarding servers) : Adding a web proxy forwarding server
  
Adding a web proxy forwarding server
To add a forwarding server, select Create New in the Web Proxy Forwarding Servers section of the Explicit Proxy page by going to System > Network > Explicit Proxy.
Server Name
Enter the name of the forwarding server.
Proxy Address
Enter the IP address of the forwarding server.
Proxy Address Type
Select the type of IP address of the forwarding server. A forwarding server can have an FQDN or IP address.
Port
Enter the port number on which the proxy receives connections. Traffic leaving the FortiGate explicit web proxy for this server has its destination port number changed to this number.
Server Down action
Select what action the explicit web proxy to take if the forwarding server is down.
• Block means if the remote server is down block traffic.
• Use Original Server means do not forward traffic to the forwarding sever but instead forward it from the FortiGate to its destination. In other words operate as if there is no forwarding server configured.
Enable Health Monitor
Select to enable health check monitoring and enter the address of a remote site. See “Web proxy forwarding server monitoring and health checking”.
Health Check Monitor Site
Use the following CLI command to add a web proxy forwarding server named fwd-srv at address proxy.example.com and port 8080.
config web-proxy forward-server
edit fwd-srv
set addr-type fqdn
set fqdn proxy.example.com
set port 8080
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