diff --git a/README.md b/README.md
index d4f3fa3..aaa5f68 100644
--- a/README.md
+++ b/README.md
@@ -1,7 +1,7 @@
 A Django app for managing computer equipment.
 
 ## Installation
-    sudo apt-get install libmysqlclient-dev python-dev libldap2-dev libsasl2-dev bind9utils
+    sudo apt install libmysqlclient-dev python-dev libldap2-dev libsasl2-dev bind9utils
     virtualenv venv
     . venv/bin/activate
     pip install -r requirements.txt
diff --git a/mdb/fixtures/test_data.json b/mdb/fixtures/test_data.json
index 0ef9f9a..5b2e24f 100644
--- a/mdb/fixtures/test_data.json
+++ b/mdb/fixtures/test_data.json
@@ -39,7 +39,7 @@
         "domain_serial": 2015100301,
         "domain_refresh": 28800,
         "domain_name": "edb.technology",
-        "domain_filename": "/tmp/mdb/bind/edb.technology",
+        "domain_filename": "/tmp/bind-db.edb.technology",
         "domain_minimum_ttl": 86400,
         "domain_expire": 604800,
         "domain_soa": "sega.neuf.no",
@@ -81,7 +81,7 @@
         "netmask": "255.255.255.0",
         "dhcp_dynamic_start": "10.0.3.2",
         "domain_admin": "sysadmin@neuf.no",
-        "domain_filename": "/tmp/mdb/bind/3.0.10.in-addr.arpa",
+        "domain_filename": "/tmp/bind-db.3.0.10.in-addr.arpa",
         "domain_minimum_ttl": 86400,
         "domain_expire": 604800,
         "dhcp_dynamic": true,
diff --git a/mdb/models.py b/mdb/models.py
index 26b1bc3..0a8ed52 100644
--- a/mdb/models.py
+++ b/mdb/models.py
@@ -222,17 +222,15 @@ class DhcpConfig(models.Model):
         # time to write host definitions
         for subnet in self.ip4subnet_set.all():
             for ip4address in subnet.ip4address_set.all():
-                if ip4address.interface_set.count() == 0:
+                if not hasattr(ip4address, 'interface') or not ip4address.interface.dhcp_client:
                     continue
-                interface = ip4address.interface_set.get()
-                if not interface.dhcp_client:
-                    continue
-                content += "\nhost %s {\n" % interface.host.hostname
-                content += "\thardware ethernet %s;\n" % interface.macaddr
+                _if = ip4address.interface
+                content += "\nhost %s {\n" % _if.host.hostname
+                content += "\thardware ethernet %s;\n" % _if.macaddr
                 content += "\tfixed-address %s.%s;\n" % \
-                    (interface.host.hostname, interface.domain.domain_name)
-                if len(interface.pxe_filename) > 0:
-                    content += "\tfilename \"%s\";\n" % interface.pxe_filename
+                    (_if.host.hostname, _if.domain.domain_name)
+                if len(_if.pxe_filename) > 0:
+                    content += "\tfilename \"%s\";\n" % _if.pxe_filename
                 content += "}\n"
 
         return content
@@ -388,26 +386,18 @@ class Ip4Subnet(models.Model):
         content += ";\n"
 
         for addr in self.ip4address_set.all():
-            if addr.interface_set.count() == 0 and generate_unassigned:
+            """ Get PTR records for each v4 address in subnet """
+            if hasattr(addr, 'interface') and addr.interface.domain:
+                hostname = "%s.%s" % (
+                    addr.interface.host.hostname,
+                    addr.interface.domain.domain_name)
+                content += "%-20s\tIN\tPTR\t%s.\n" % \
+                    (addr.address.split(".")[3], hostname)
+            elif not hasattr(addr, 'interface') and generate_unassigned:
                 content += "%s\tIN\tPTR\t%s.%s\n" % (
                     addr.address,
                     addr.address.split(".")[3],
                     "dhcp.neuf.no.")
-                continue
-
-            for interface in addr.interface_set.all():
-                if interface.domain is None and generate_unassigned:
-                    content += "%s\tIN\tPTR\t%s.%s.\n" % (
-                        addr.address,
-                        addr.address.split(".")[3],
-                        "dhcp.neuf.no")
-
-                else:
-                    hostname = "%s.%s" % (
-                        interface.host.hostname,
-                        interface.domain.domain_name)
-                    content += "%-20s\tIN\tPTR\t%s.\n" % \
-                        (addr.address.split(".")[3], hostname)
 
         return content
 
diff --git a/mdb/tests.py b/mdb/tests.py
index 6c975cf..7581525 100644
--- a/mdb/tests.py
+++ b/mdb/tests.py
@@ -1,6 +1,8 @@
 from django.contrib.auth.models import User
+from django.core.management import call_command
 from django.core.urlresolvers import reverse
-from django.test import TestCase
+from django.test import TestCase, LiveServerTestCase
+from django.utils import six
 from rest_framework.authtoken.models import Token
 from rest_framework.test import APITestCase
 
@@ -36,3 +38,19 @@ class UnitTests(TestCase):
     def test_host_as_pxe_files(self):
         host = Host.objects.first()
         self.assertEqual(len(host.as_pxe_files()), 1)
+
+
+class RunManagementCommands(TestCase):
+    fixtures = ['test_data']
+
+    def test_zone_sync(self):
+        expected_zone_file = ''
+        with six.BytesIO() as f:
+            call_command('zone-sync', debug=True, stdout=f)
+        # TODO check expected_zone_file
+
+    def test_dhcp_sync(self):
+        expected_dhcp_file = ''
+        with six.BytesIO() as f:
+            call_command('dhcp-sync', ('--debug',), stdout=f)
+        # TODO check expected_dhcp_file