title: Ubuntu 11.10 dhclient-enter-hook.d scripts not invoked
body: <p>I have a box with Ubuntu 11.10 installed. And the box was configured to get IP and hostname from dhcp.</p>
  
  <p>We have set to scripts in /etc/dhcp/dhclient-enter-hooks.d/ folder. But these scripts were not invoked/executed. I have similar scripts in another box, which has Ubuntu 10.04  installed and hook scripts executes without issues. One difference is that in the 11.10 box has NetworkManager installed.</p>
  
  <pre><code># ps -ef | grep dhclient
  root       746   695  0 03:52 ?        00:00:00 /sbin/dhclient -d -4 -sf /usr/lib/NetworkManager/nm-dhcp-client.action -pf /var/run/dhclient-eth0.pid -lf /var/lib/dhcp/dhclient-559273da-a027-458e-b124-bdbb4976ee17-eth0.lease -cf /var/run/nm-dhclient-eth0.conf eth0
  </code></pre>
  
  <p>How did I test that the script in /etc/dhcp/dhclient-enter-hooks.d was not running?
  I have placed a simple script "mytest" which has below code in /etc/dhcp/dhclient-enter-hooks.d. The file /tmp/enter-hook.out was never generated.</p>
  
  <pre><code>#!/bin/sh
  echo "this is test file to test dhclient-enter-hook" &gt; /tmp/enter-hook.out
  </code></pre>
  
  <p>Snip of my /etc/network/interfaces</p>
  
  <pre><code># cat /etc/network/interfaces 
  auto lo
  iface lo inet loopback
  
  auto eth0 inet dhcp
  </code></pre>