Chapter 23 WAN Optimization, Web Cache, Explicit Proxy, and WCCP : Configuring WAN optimization : Manual (peer-to-peer) and active-passive WAN optimization : Active-passive configurations : Server-side passive policy
  
Server-side passive policy
Add a passive policy to the server-side FortiGate unit by selecting Enable WAN Optimization and selecting passive. Then set the Passive Option to transparent. From the CLI the policy could look like the following:
config firewall policy
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set srcintf "wan1"
set dstintf "internal"
set srcaddr "all"
set dstaddr "all"
set action accept
set schedule "always"
set service "ANY"
set wanopt enable
set wanopt-detection passive
set wanopt-passive-opt transparent
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