diff --git a/database-update.sql b/database-update.sql
index 878cbb1bc..115f1d1f1 100644
--- a/database-update.sql
+++ b/database-update.sql
@@ -88,4 +88,5 @@ ALTER TABLE  `temperature` CHANGE  `temp_host`  `device_id` INT( 11 ) NOT NULL D
 ALTER TABLE  `fanspeed` CHANGE  `fan_host`  `device_id` INT( 11 ) NOT NULL DEFAULT  '0'
 ALTER TABLE  `voltage` CHANGE  `volt_host`  `device_id` INT( 11 ) NOT NULL DEFAULT  '0'
 CREATE TABLE IF NOT EXISTS `processors` (  `processor_id` int(11) NOT NULL AUTO_INCREMENT,  `entPhysicalIndex` int(11) NOT NULL,  `device_id` int(11) NOT NULL,  `processor_oid` int(11) NOT NULL,  `processor_type` int(11) NOT NULL,  `processor_usage` int(11) NOT NULL,  `processor_description` varchar(64) NOT NULL,  PRIMARY KEY (`processor_id`),  KEY `cpuCPU_id` (`processor_id`,`device_id`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 AUTO_INCREMENT=1 ;
-ALTER TABLE  `processors` ADD `hrDeviceIndex` int(11) NOT NULL AFTER `entPhysicalIndex`
+ALTER TABLE  `processors` ADD `hrDeviceIndex` int(11) NULL AFTER `entPhysicalIndex`
+ALTER TABLE  `temperature` CHANGE  `temp_current`  `temp_current` FLOAT( 4 ) NOT NULL DEFAULT  '0'
diff --git a/discovery.php b/discovery.php
index 669d3840e..cf824449d 100755
--- a/discovery.php
+++ b/discovery.php
@@ -4,6 +4,7 @@
 include("config.php");
 include("includes/functions.php");
 include("includes/functions-poller.inc.php");
+include("includes/discovery/functions.inc.php");
 
 $start = utime();
 
diff --git a/includes/defaults.inc.php b/includes/defaults.inc.php
index 25a6273e1..58c4e1ffd 100644
--- a/includes/defaults.inc.php
+++ b/includes/defaults.inc.php
@@ -68,6 +68,11 @@ $config['allow_entity_sensor']['watts'] = 1;
 $config['allow_entity_sensor']['truthvalue'] = 1;
 $config['allow_entity_sensor']['specialEnum'] = 1;
 
+# Set default alert limits for various sensors and metrics
+
+$config['limit']['fan']  = "1000";
+$config['limit']['temp'] = "60";
+
 # Filesystems
 
 $config['ignore_mount'] = array("/kern", "/mnt/cdrom", "/proc");
@@ -76,6 +81,4 @@ $config['ignore_mount_regexp'] = array();
 $config['ignore_mount_removable'] = 1; # Ignore removable disk storage
 $config['ignore_mount_network']   = 1; # Ignore network mounted storage
 
-
-
 ?>
diff --git a/includes/polling/fanspeeds.inc.php b/includes/polling/fanspeeds.inc.php
index e76f4af1a..2e2d64ccb 100755
--- a/includes/polling/fanspeeds.inc.php
+++ b/includes/polling/fanspeeds.inc.php
@@ -14,7 +14,7 @@ while($fanspeed = mysql_fetch_array($fan_data)) {
   $fanrrd  = $config['rrd_dir'] . "/" . $device['hostname'] . "/" . safename("fan-" . $fanspeed['fan_descr'] . ".rrd");
 
   if (!is_file($fanrrd)) {
-    `rrdtool create $fanrrd \
+     `rrdtool create $fanrrd \
      --step 300 \
      DS:fan:GAUGE:600:0:20000 \
      RRA:AVERAGE:0.5:1:1200 \