diff --git a/src/www/services_router_advertisements.php b/src/www/services_router_advertisements.php
index b6da8486f..0b7483571 100644
--- a/src/www/services_router_advertisements.php
+++ b/src/www/services_router_advertisements.php
@@ -117,36 +117,36 @@ if ($_SERVER['REQUEST_METHOD'] === 'GET') {
     if (!val_int_in_range($pconfig['ramaxinterval'], 4, 1800)) {
         $input_errors[] = sprintf(gettext('Maximum interval must be between %s and %s seconds.'), 4, 1800);
     } else {
+        $int_max = 4294967295;
+
         if (!val_int_in_range($pconfig['ramininterval'], 3, intval($pconfig['ramaxinterval'] * 0.75))) {
             $input_errors[] = sprintf(gettext('Minimum interval must be between %s and %s seconds.'), 3, intval($pconfig['ramaxinterval'] * 0.75));
         }
         if (!empty($pconfig['AdvDefaultLifetime']) && !val_int_in_range($pconfig['AdvDefaultLifetime'], $pconfig['ramaxinterval'], 9000)) {
             $input_errors[] = sprintf(gettext('AdvDefaultLifetime must be between %s and %s seconds.'), $pconfig['ramaxinterval'], 9000);
         }
-        if (!empty($pconfig['AdvValidLifetime']) && !val_int_in_range($pconfig['AdvValidLifetime'], 1, 4294967295)) {
-            $input_errors[] = sprintf(gettext('AdvValidLifetime must be between %s and %s seconds.'),  1, 4294967295);
+        if (!empty($pconfig['AdvValidLifetime']) && !val_int_in_range($pconfig['AdvValidLifetime'], 1, $int_max)) {
+            $input_errors[] = sprintf(gettext('AdvValidLifetime must be between %s and %s seconds.'), 1, $int_max);
         }
-        if (!empty($pconfig['AdvPreferredLifetime']) && !val_int_in_range($pconfig['AdvPreferredLifetime'], 1, 4294967295)) {
-            $input_errors[] = sprintf(gettext('AdvPreferredLifetime must be between %s and %s seconds.'),  1, 4294967295);
+        if (!empty($pconfig['AdvPreferredLifetime']) && !val_int_in_range($pconfig['AdvPreferredLifetime'], 1, $int_max)) {
+            $input_errors[] = sprintf(gettext('AdvPreferredLifetime must be between %s and %s seconds.'), 1, $int_max);
         }
-        if (!empty($pconfig['AdvRDNSSLifetime']) && !val_int_in_range($pconfig['AdvRDNSSLifetime'], $pconfig['ramaxinterval'], $pconfig['ramaxinterval'] * 2)) {
-            $input_errors[] = sprintf(gettext('AdvRDNSSLifetime must be between %s and %s seconds.'),  $pconfig['ramaxinterval'], $pconfig['ramaxinterval'] * 2);
+        if (!empty($pconfig['AdvRDNSSLifetime']) && !val_int_in_range($pconfig['AdvRDNSSLifetime'], 1, $int_max)) {
+            $input_errors[] = sprintf(gettext('AdvRDNSSLifetime must be between %s and %s seconds.'), 1, $int_max);
         }
-        if (!empty($pconfig['AdvDNSSLLifetime']) && !val_int_in_range($pconfig['AdvDNSSLLifetime'], $pconfig['ramaxinterval'], $pconfig['ramaxinterval'] * 2)) {
-            $input_errors[] = sprintf(gettext('AdvDNSSLLifetime must be between %s and %s seconds.'),  $pconfig['ramaxinterval'], $pconfig['ramaxinterval'] * 2);
+        if (!empty($pconfig['AdvDNSSLLifetime']) && !val_int_in_range($pconfig['AdvDNSSLLifetime'], 1, $int_max)) {
+            $input_errors[] = sprintf(gettext('AdvDNSSLLifetime must be between %s and %s seconds.'), 1, $int_max);
         }
-        if (!empty($pconfig['AdvRouteLifetime']) && !val_int_in_range($pconfig['AdvRouteLifetime'], 1, 4294967295)) {
-            $input_errors[] = sprintf(gettext('AdvRouteLifetime must be between %s and %s seconds.'),  1, 4294967295);
+        if (!empty($pconfig['AdvRouteLifetime']) && !val_int_in_range($pconfig['AdvRouteLifetime'], 1, $int_max)) {
+            $input_errors[] = sprintf(gettext('AdvRouteLifetime must be between %s and %s seconds.'), 1, $int_max);
         }
         $mtu_low = 1280;
         $mtu_high = 65535;
         if (!empty($pconfig['AdvLinkMTU']) && !val_int_in_range($pconfig['AdvLinkMTU'], $mtu_low, $mtu_high)) {
-            $input_errors[] = sprintf(gettext('AdvLinkMTU must be between %s and %s bytes.'),  $mtu_low, $mtu_high);
+            $input_errors[] = sprintf(gettext('AdvLinkMTU must be between %s and %s bytes.'), $mtu_low, $mtu_high);
         }
     }
 
-
-
     if (count($input_errors) == 0) {
         config_read_array('dhcpdv6', $if);