diff --git a/CHANGELOG.md b/CHANGELOG.md
index 8f75a353..dee9220e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -28,6 +28,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - pkgs: Add requirement on RFL.core >= 1.0.3.
 - frontend: Add intermediate cluster list width to 80% on large screens, before
   going down to 60% on even larger screens.
+- docs: Update configuration reference documentation.
 
 ### Fixed
 - backend: handle rfl.settings.errors.SettingsSiteLoaderError when loading
diff --git a/docs/modules/conf/examples/gateway.ini b/docs/modules/conf/examples/gateway.ini
index 8a8647b8..d8406ac5 100644
--- a/docs/modules/conf/examples/gateway.ini
+++ b/docs/modules/conf/examples/gateway.ini
@@ -150,11 +150,25 @@ user_name_attribute=uid
 # Default value: cn
 user_fullname_attribute=cn
 
+# User entry attribute for primary group ID
+#
+# Default value: gidNumber
+user_primary_group_attribute=gidNumber
+
 # Group entry attribute for name
 #
 # Default value: cn
 group_name_attribute=cn
 
+# List of LDAP object classes for groups
+#
+# Default value:
+# - posixGroup
+# - groupOfNames
+group_object_classes=
+  posixGroup
+  groupOfNames
+
 # DN used to bind to the LDAP server. When this parameter is not defined,
 # access to LDAP directory is performed anonymously.
 bind_dn=cn=system,ou=people,dc=example,dc=org
diff --git a/docs/modules/conf/partials/conf-gateway.adoc b/docs/modules/conf/partials/conf-gateway.adoc
index 42ea499f..4972d26e 100644
--- a/docs/modules/conf/partials/conf-gateway.adoc
+++ b/docs/modules/conf/partials/conf-gateway.adoc
@@ -366,6 +366,17 @@ _No default value_
 
 |-
 
+|user_primary_group_attribute
+|str
+|User entry attribute for primary group ID
+
+
+
+
+*Default:* `gidNumber`
+
+|-
+
 |group_name_attribute
 |str
 |Group entry attribute for name
@@ -375,6 +386,23 @@ _No default value_
 
 *Default:* `cn`
 
+|-
+
+|group_object_classes
+|list[str]
+|List of LDAP object classes for groups
+
+
+
+
+*Default:*
+
+
+* `posixGroup`
+
+* `groupOfNames`
+
+
 |-
 
 |bind_dn