diff --git a/etherswitch.sh b/etherswitch.sh
index cc62727..2c808b7 100755
--- a/etherswitch.sh
+++ b/etherswitch.sh
@@ -5,28 +5,35 @@ switch_state=0
 
 function check_fn {
     type $1 &> /dev/null || {
-	echo "$1 is undefined"
+	>&2 echo "$1 is undefined"
 	exit 1
     }
 }
 
-source $conf
+function load_config {
+    unset -f on_switch_close
+    unset -f on_switch_open
+    source $conf
+    if [ -z "$device" ]
+    then
+	>&2 echo "device is not set"
+	exit 1
+    fi
+    # check if $device is a network device
+    ip link show $device > /dev/null
+    if [ $? -eq 1 ]; then exit 1; fi
+
+    check_fn "on_switch_close"
+    check_fn "on_switch_open"
+}
 
 # handle SIGTERM
 trap 'exit' 15
 
-if [ -z "$device" ]
-then
-    echo "device is not set"
-    exit 1
-fi
+# handle SIGHUP (config reload)
+trap 'load_config' 1
 
-# check if $device is a network device
-ip link show $device > /dev/null
-if [ $? -eq 1 ]; then exit 1; fi   
-
-check_fn "on_switch_close"
-check_fn "on_switch_open"
+load_config
 
 while :
 do