diff --git a/interface/web/dns/dns_edit_base.php b/interface/web/dns/dns_edit_base.php
index 61c08f6576a9f6eff032b249728d2a0e2210d56e..a4e314381aedddac19dd5e6c7aee7f6abd15e485 100644
--- a/interface/web/dns/dns_edit_base.php
+++ b/interface/web/dns/dns_edit_base.php
@@ -41,6 +41,10 @@ $app->load('tform_actions');
 class dns_page_action extends tform_actions {
 
 	protected function checkDuplicate() {
+                 global $app;
+                // If a CNAME RR is present at a node, no other data should be present
+                $tmp = $app->db->queryOneRecord("SELECT count(id) as number FROM dns_rr WHERE (type = 'CNAME' AND name = ? AND zone = ? and id != ?)", $this->dataRecord["name"], $this->dataRecord["zone"], $this->id);
+                if($tmp['number'] > 0) return true;
 		return false;
 	}