diff --git a/config/sample-config2.yaml b/config/sample-config2.yaml
index 0145f3e..fa29f12 100644
--- a/config/sample-config2.yaml
+++ b/config/sample-config2.yaml
@@ -37,10 +37,9 @@ ldap_groups:
   # lowercase name for use as PG role name
   lowercase_name: false
   # this attribute must reference to all member DN's of the given group
-  # If LDAP server is Active Directory, it's better to append ";range" to member_attribue; 
-  # otherwise, it can't synchronize groups with over 1500 users for AD server.
-  # Example for AD server: "member;range"  
   member_attribute: member
+  # must be true if group with over 1500 members for Active Directory server
+  need_member_range_retrieval: false
 
 # Connection parameters to PostgreSQL server
 # see also: http://rubydoc.info/gems/pg/PG/Connection#initialize-instance_method
diff --git a/config/schema.yaml b/config/schema.yaml
index 08abdb8..227de45 100644
--- a/config/schema.yaml
+++ b/config/schema.yaml
@@ -46,6 +46,9 @@ mapping:
       "member_attribute":
         type: str
         required:  yes
+      "need_member_range_retrieval":
+        type: bool
+        required:  no
 
   "pg_connection":
     type:      any
diff --git a/lib/pg_ldap_sync/application.rb b/lib/pg_ldap_sync/application.rb
index 73d8728..90c7ec2 100644
--- a/lib/pg_ldap_sync/application.rb
+++ b/lib/pg_ldap_sync/application.rb
@@ -90,7 +90,7 @@ class Application
     all_group_members = []
     while true do
       member_size = 0
-      member_attribute_with_range = "#{@config[:ldap_groups][:member_attribute]}=#{range_start}-*"
+      member_attribute_with_range = "#{@config[:ldap_groups][:member_attribute]};range=#{range_start}-*"
       returned_member_attribute_with_range = ""
       log.debug " current attribute for range retrieval ----> #{member_attribute_with_range} "
 
@@ -141,9 +141,8 @@ class Application
       end
 
       names.each do |n|
-        member_attribute_sub_list = ldap_group_conf[:member_attribute].partition(";")
-        group_members = entry[member_attribute_sub_list[0]]
-        if group_members.count == 0 and member_attribute_sub_list[2] == "range"
+        group_members = entry[ldap_group_conf[:member_attribute]]
+        if group_members.count == 0 and ldap_group_conf[:need_member_range_retrieval]
           group_members = load_group_members_by_range(entry.dn)
         end
         groups << LdapRole.new(n, entry.dn, group_members)