diff --git a/html/pages/device/showconfig.inc.php b/html/pages/device/showconfig.inc.php
index dd8af7cc2..c79c4aacb 100644
--- a/html/pages/device/showconfig.inc.php
+++ b/html/pages/device/showconfig.inc.php
@@ -105,51 +105,60 @@ if (is_admin()) {
     else if ($config['oxidized']['enabled'] === true && isset($config['oxidized']['url'])) {
         // fetch info about the node and then a list of versions for that node
         $node_info = json_decode(file_get_contents($config['oxidized']['url'].'/node/show/'.$device['hostname'].'?format=json'), true);
-        $config_versions = json_decode(file_get_contents($config['oxidized']['url'].'/node/version?node_full='.(!empty($node_info['group']) ? $node_info['group'].'/' : '').$device['hostname'].'&format=json'), true);
+        $config_versions = json_decode(file_get_contents($config['oxidized']['url'].'/node/version?node_full='.(isset($node_info['full_name']) ? $node_info['full_name'] : $device['hostname']).'&format=json'), true);
 
         if (is_array($config_versions)) {
             $config_total = count($config_versions);
         }
 
         if ($config_total > 1) {
-            if (isset($_POST['config'])) {  // versioning with selected version
+            // populate current_version
+            if (isset($_POST['config'])) {
                 list($oid,$date,$version) = explode('|',mres($_POST['config']));
-                $current_version = array('oid'=>$oid, 'date'=>$date, 'version'=>$version);
+                $current_config = array('oid'=>$oid, 'date'=>$date, 'version'=>$version);
             }
             else { // no version selected
-                $current_version = array('oid'=>$config_versions[0]['oid'], 'date'=>$current_version[0]['date'], 'version'=>$config_total);
+                $current_config = array('oid'=>$config_versions[0]['oid'], 'date'=>$current_config[0]['date'], 'version'=>$config_total);
             }
 
-            // fetch current_version
-            $text = file_get_contents($config['oxidized']['url'].'/node/version/view?node='.$device['hostname'].'&group='.(!empty($node_info['group']) ? $node_info['group'] : '').'&oid='.$current_version['oid'].'&date='.urlencode($current_version['date']).'&num='.$current_version['version'].'&format=text');
-
-            if (isset($_POST['diff']) && isset($_POST['prevconfig'])) { // diff requested
+            // populate previous_version
+            if (isset($_POST['diff'])) { // diff requested
                 list($oid,$date,$version) = explode('|',mres($_POST['prevconfig']));
-                if ($current_version['oid'] == $oid) { // the same version is selected, assume the previous revision
+                if (isset($oid) && $oid != $current_config['oid']) {
+                    $previous_config = array('oid'=>$oid, 'date'=>$date, 'version'=>$version);
+                }
+                else if ($current_config['version'] != 1) {  // assume previous, unless current is first config
                     foreach ($config_versions as $key => $version) {
-                        if ($version['oid'] == $current_version['oid']) {
+                        if ($version['oid'] == $current_config['oid']) {
                             $prev_key = $key + 1;
-                            $oid = $config_versions[$prev_key]['oid'];
-                            $date = $config_versions[$prev_key]['date'];
-                            $version = $config_total - $prev_key;
+                            $previous_config['oid']     = $config_versions[$prev_key]['oid'];
+                            $previous_config['date']    = $config_versions[$prev_key]['date'];
+                            $previous_config['version'] = $config_total - $prev_key;
                             break;
                         }
                     }
                 }
-
-                if ($version > 0) { // if we know the version doesn't exist, don't even try to fetch it
-                    $previous_text = file_get_contents($config['oxidized']['url'].'/node/version/view?node='.$device['hostname'].'&group='.(!empty($node_info['group']) ? $node_info['group'] : '').'&oid='.$oid.'&date='.urlencode($date).'&num='.$version.'&format=text');
-                    if (!empty($previous_text)) {
-                        $previous_version = array('oid'=>$oid, 'date'=>$date, 'version'=>$version);
-                        $text = xdiff_string_diff($text, $previous_text); // requires pecl xdiff
-                    }
-                } else {
+                else {
                     print_error('No previous version, please select a different version.');
                 }
             }
+
+            if (isset($previous_config)) {
+                $url = $config['oxidized']['url'].'/node/version/diffs?node='.$device['hostname'].'&group=';
+                if (!empty($node_info['group'])) {
+                    $url .= $node_info['group'];
+                }
+                $url .= '&oid='.$previous_config['oid'].'&date='.urlencode($previous_config['date']).'&num='.$previous_config['version'].'&oid2='.$current_config['oid'].'&format=text';
+
+                $text = file_get_contents($url); // fetch diff
+            } else {
+                // fetch current_version
+                $text = file_get_contents($config['oxidized']['url'].'/node/version/view?node='.$device['hostname'].'&group='.(!empty($node_info['group']) ? $node_info['group'] : '').'&oid='.$current_config['oid'].'&date='.urlencode($current_config['date']).'&num='.$current_config['version'].'&format=text');
+            }
         }
         else {  // just fetch the only version
             $text = file_get_contents($config['oxidized']['url'].'/node/fetch/'.(!empty($node_info['group']) ? $node_info['group'].'/' : '').$device['hostname']);
+
         }
 
         if (is_array($node_info) || $config_total > 1) {
@@ -186,15 +195,15 @@ if (is_admin()) {
                 $i = $config_total;
                 foreach ($config_versions as $version) {
                     echo '<option value="'.$version['oid'].'|'.$version['date'].'|'.$config_total.'" ';
-                    if ($current_version['oid'] == $version['oid']) {
-                        if (is_array($previous_version)) {
+                    if ($current_config['oid'] == $version['oid']) {
+                        if (isset($previous_config)) {
                             echo 'selected>+';
                         }
                         else {
                             echo 'selected>*';
                         }
                     }
-                    else if ($previous_version['oid'] == $version['oid']) {
+                    else if ($previous_config['oid'] == $version['oid']) {
                         echo '>&nbsp;-';
                     }
                     else {
@@ -211,7 +220,7 @@ if (is_admin()) {
                             <div class="form-group">
                                 <div class="col-sm-offset-2 col-sm-6">
                                       <input type="hidden" name="prevconfig" value="';
-                echo implode('|',$current_version);
+                echo implode('|',$current_config);
                 echo '">
                                       <button type="submit" class="btn btn-primary btn-sm" name="show">Show version</button>
                                       <button type="submit" class="btn btn-primary btn-sm" name="diff">Show diff</button>
@@ -232,13 +241,13 @@ if (is_admin()) {
     }//end if
 
     if (!empty($text)) {
-        if (is_array($previous_version)) {
+        if (isset($previous_config)) {
             $language = 'diff';
         } else {
             $language = 'ios';
         }
         $geshi = new GeSHi($text, $language);
-//        $geshi->enable_line_numbers(GESHI_FANCY_LINE_NUMBERS);
+        $geshi->enable_line_numbers(GESHI_FANCY_LINE_NUMBERS);
         $geshi->set_overall_style('color: black;');
         // $geshi->set_line_style('color: #999999');
         echo '<div class="config">';