Merge pull request #274013 from wtnlee/patch-15

Update how-to-routing-policies.md

Author: prmerger-automator[bot]

articles/virtual-wan/how-to-routing-policies.md

@@ -106,6 +106,7 @@ Before enabling routing intent, consider the following:
 * Routing intent changes the static routes in the defaultRouteTable. Due to Azure portal optimizations, the state of the defaultRouteTable after routing intent is configured may be different if you configure routing intent using REST, CLI or PowerShell. For more information, see [static routes](#staticroute).
 * Enabling routing intent affects the advertisement of prefixes to on-premises. See [prefix advertisements](#prefixadvertisments) for more information.
 * You may open a support case to enable connectivity across ExpressRoute  circuits via a Firewall appliance in the hub. Enabling this connectivity pattern modifies the prefixes advertised to ExpressRoute circuits. See [About ExpressRoute](#expressroute) for more information.
+* Routing intent is the only mechanism in Virtual WAN to enable inter-hub traffic inspection via security appliances deployed in the hub. Inter-hub traffic inspection also requires routing intent to be enabled on all hubs to ensure traffic is routed symmetrically between security appliances deployed in Virtual WAN hubs. 
 
 ### <a name="prereq"></a> Prerequisites