diff --git a/Dockerfile b/Dockerfile
index 9104c9a..acd5152 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,8 +1,11 @@
 FROM ubuntu:trusty
 MAINTAINER Dave P
 
+ADD start /start
+
 # Install bind and dns utils
-RUN apt-get update ; \
+RUN chmod +x /start ; \
+    apt-get update ; \
     apt-get install -y supervisor bind9 dnsutils ; \
     rm /etc/bind/rndc.key ; \
     mkdir /var/run/named ; \
@@ -11,8 +14,8 @@ RUN apt-get update ; \
     touch /var/log/named.log ; \
     chgrp bind /var/log/named.log ; \
     chmod 775 /var/log/named.log ; \
-    sed -i -e's/include "\/etc\/bind\/named.conf.options";/logging{\n\tchannel simple_log {\n\t\tfile "\/var\/log\/named.log" versions 3 size 5m;\n\t\tseverity info;\n\t\tprint-time yes;\n\t\tprint-severity yes;\n\t\tprint-category yes;\n\t};\n\tcategory default{\n\t\tsimple_log;\n\t};\n};\ninclude "\/etc\/bind\/named.conf.options";/' /etc/bind/named.conf ; \
-    mkdir /start.d
+    mkdir /start.d ; \
+    rm -rf /var/lib/apt/lists/*
 
 # Supervisor script
 ADD bind.conf /etc/supervisor/conf.d/bind.conf
@@ -21,8 +24,7 @@ ADD supervisor.conf /etc/supervisor/conf.d/supervisor.conf
 # Bind setup script
 ADD regen-bind-key /start.d/regen-bind-key
 
-ADD start /start
-
 # DNS port
 EXPOSE 53/udp
 
+ENTRYPOINT ["/start"]
\ No newline at end of file
diff --git a/regen-bind-key b/regen-bind-key
index dd95ca0..ea58071 100755
--- a/regen-bind-key
+++ b/regen-bind-key
@@ -1,7 +1,6 @@
 #!/bin/bash
 
 # reconfigure bind - regenerates secret keys
-rndc-confgen -a -r /dev/urandom
-
-# Only run once
-rm /start.d/regen-bind-key
+if [ ! -f /etc/bind/rndc.key ]; then
+    rndc-confgen -a -r /dev/urandom
+fi