gistfile1.txt

diff --git a/dhcp.py b/dhcp.py
index 2844b1a..fc72f37 100644
--- a/dhcp.py
+++ b/dhcp.py
@@ -31,6 +31,7 @@ from quantum.agent.linux import utils
 from quantum.openstack.common import jsonutils
 from quantum.openstack.common import log as logging
 from quantum.openstack.common import uuidutils
+from novaclient.v1_1 import client

 LOG = logging.getLogger(__name__)

@@ -355,13 +356,46 @@ class Dnsmasq(DhcpLocalProcess):
         r = re.compile('[:.]')
         buf = StringIO.StringIO()

+        # get credentials from /root/openrc
+        env_creds = {}
+
+        if os.path.isfile('/var/lib/quantum/openrc'):
+
+            try:
+                with open('/var/lib/quantum/openrc', 'r') as f:
+                    env_lines = f.readlines()
+                    for line in env_lines:
+                        match = re.search(r'export (\S+)=(\S+)', line)
+                        if match:
+                            key, value = match.groups()
+                            env_creds[key] = value
+            except:
+                LOG.exception("There was an error processing /var/lib/quantum/openrc for credentials")
+
+            # create a connection to nova so we can map port IDs to vm hostnames
+            try:
+                nova = client.Client(username=env_creds['OS_USERNAME'],
+                                     api_key=env_creds['OS_PASSWORD'],
+                                     auth_url=env_creds['OS_AUTH_URL'],
+                                     project_id=env_creds['OS_TENANT_NAME'])
+            except:
+                LOG.exception("There was an error initializing the nova client to lookup associated port hostnames")
+
         for port in self.network.ports:
             for alloc in port.fixed_ips:
-                name = '%s.%s' % (r.sub('-', alloc.ip_address),
-                                  self.conf.dhcp_domain)
+                try:
+                    server = nova.servers.get(port.device_id)
+                    name = '%s.%s' % (server.name,
+                                      self.conf.dhcp_domain)
+                    # do some simple replacement of common invalid dns characters
+                    name = name.replace(' ', '-')
+                    name = name.replace('_', '-')
+                except:
+                    LOG.debug("An error occurred while fetching the hostname for port.device_id = %s falling back to using the mac address" % port.device_id)
+                    name = '%s.%s' % (r.sub('-', alloc.ip_address),
+                                      self.conf.dhcp_domain)
                 buf.write('%s,%s,%s\n' %
                           (port.mac_address, name, alloc.ip_address))
-
         name = self.get_conf_file_name('host')
         utils.replace_file(name, buf.getvalue())
         return name

This helped me a lot - thank you very much!

You might want to harden line 26-28 though, I had
export OS_AUTH_URL="http..."
(with quotation marks) in my openrc file and it broke everything