In previous versions of StoreFront servers (2.6 or older), Citrix recommended to manually modify the hosts file on each StoreFront server to map FQDN of the load balancer to the IP address of the specific StoreFront server or the loopback address.
This is necessary because an HTTP session is created during the explicit login process between Receiver for Web and the authentication service and Receiver for Web communicates with StoreFront services using the base FQDN. If the base FQDN were to resolve to the load balancer, the load balancer could potentially send the traffic to a different StoreFront server in the group, leading to authentication failure.
By doing this Receiver for Web always communicates with the StoreFront services on the same server in a load balanced StoreFront deployment.
You can set loopback options using PowerShell. Enabling loopback negates the need to create host file entries on every StoreFront server in the server group.
Example – Receiver for Web web.config file:
<communication attempts=”2″ timeout=”00:01:00″ loopback=”On” loopbackPortUsingHttp=”80″>
Example – PowerShell command:
& “c:\program files\Citrix\receiver storefront\scripts\ImportModules.ps1”
Set-DSLoopback -SiteId 1 -VirtualPath “/Citrix/StoreWeb” -Loopback “OnUsingHttp” -LoopbackPortUsingHttp81
From StoreFront 3.0, we can enable loopback in the StoreFront Console.