diff --git a/admin_manual/configuration_server/config_sample_php_parameters.rst b/admin_manual/configuration_server/config_sample_php_parameters.rst
index 1237f8086..9dce20b29 100644
--- a/admin_manual/configuration_server/config_sample_php_parameters.rst
+++ b/admin_manual/configuration_server/config_sample_php_parameters.rst
@@ -66,6 +66,13 @@ Your list of trusted domains that users can log into. Specifying trusted
 domains prevents host header poisoning. Do not remove this, as it performs
 necessary security checks.
 
+You can specify:
+- the exact hostname of your host or virtual host, e.g. demo.example.org.
+- the exact hostname with permitted port, e.g. demo.example.org:443.
+  This disallows all other ports on this host
+- use * as a wildcard, e.g. ubos-raspberry-pi*.local will allow
+  ubos-raspberry-pi.local and ubos-raspberry-pi-2.local
+
 ::
 
 	'datadirectory' => '/var/www/nextcloud/data',