If you have configured an Access Manager deployment as a site, Access Manager automatically sets the fqdnMap property (in memory) to include the load balancer , and you do not need to set this property in the AMConfig.properties file. However, for the following Access Manager deployments, you must explicitly set the property:
The deployment is not configured as a site.
The deployment has virtual hosts that are mapped to a physical host.
If you need to set the fqdnMap property, set the property to the load balancer in the AMConfig.properties file for each Access Manager instance in the deployment. If necessary, first remove the comment character (#) from the property. For example:
com.sun.identity.server.fqdnMap[lb.example.com]=lb.example.com