diff --git a/src/www/services_opendns.php b/src/www/services_opendns.php
index ddcfac2fd..d0020b8e2 100644
--- a/src/www/services_opendns.php
+++ b/src/www/services_opendns.php
@@ -91,7 +91,9 @@ if ($_SERVER['REQUEST_METHOD'] === 'GET') {
                 $config['system']['dnsserver'][] = $v4_server[0];
                 $config['system']['dnsserver'][] = $v4_server[1];
             }
-            $config['system']['dnsallowoverride'] = false;
+            if (isset($config['system']['dnsallowoverride'])) {
+                unset($config['system']['dnsallowoverride']);
+            }
         } else {
             $config['system']['dnsserver'] = array();
             $config['system']['dnsserver'][] = '';
diff --git a/src/www/system_general.php b/src/www/system_general.php
index cf2959009..538954f80 100644
--- a/src/www/system_general.php
+++ b/src/www/system_general.php
@@ -136,7 +136,11 @@ if ($_SERVER['REQUEST_METHOD'] === 'GET') {
             unset($config['system']['prefer_ipv4']);
         }
 
-        $config['system']['dnsallowoverride'] = !empty($pconfig['dnsallowoverride']);
+        if (!empty($pconfig['dnsallowoverride'])) {
+            $config['system']['dnsallowoverride'] = true;
+        } elseif (isset($config['system']['dnsallowoverride'])) {
+            unset($config['system']['dnsallowoverride']);
+        }
 
         if($pconfig['dnslocalhost'] == "yes") {
           $config['system']['dnslocalhost'] = true;