Load balancing : Load balancing among local servers : Distributing new sessions among your servers : Customizing the error page or message
 
Customizing the error page or message
When the virtual server type is L7 Load Balance, you can either select a file to use as an error page or enter an error message. FortiADC responds to clients with this page when layer 7 servers are not available.
To upload a custom error page, go to Server Load Balance > Resources > Error Page.
 
FortiADC does not include the uploaded error page in a configuration backup.
In a high availability FortiADC cluster, FortiADC does not synchronize the uploaded error page file to the standby appliance.