diff --git a/scripts/edgeconfig.py b/scripts/edgeconfig.py
index 7034f6c..8131335 100644
--- a/scripts/edgeconfig.py
+++ b/scripts/edgeconfig.py
@@ -11,9 +11,10 @@
 from __future__ import absolute_import
 
 import argparse
-import nbhelper
 import os
 
+import nbhelper
+
 from ruamel.yaml import YAML
 
 # main function that calls other functions
diff --git a/scripts/inventory.py b/scripts/inventory.py
new file mode 100644
index 0000000..26edcdd
--- /dev/null
+++ b/scripts/inventory.py
@@ -0,0 +1,61 @@
+#!/usr/bin/env python3
+
+# SPDX-FileCopyrightText: © 2021 Open Networking Foundation <support@opennetworking.org>
+# SPDX-License-Identifier: Apache-2.0
+
+# inventory.py
+# create an inventory file for a site, in YAML format
+# currently aether specific
+
+import nbhelper
+from ruamel import yaml
+
+if __name__ == "__main__":
+
+    extra_args = {
+        "--generic": {
+            "action": "store_true",
+            "help": "Use generic output, instead of Aether-specific",
+        },
+    }
+
+    args = nbhelper.initialize(extra_args)
+    tenant = nbhelper.Tenant()
+
+    routers = {}
+    servers = {}
+    switches = {}
+
+    for device in tenant.get_devices():
+
+        dev_name = device.data["name"]
+
+        dev_vars = {
+            "ansible_host": str(device.primary_ip),
+        }
+
+        if device.data.device_role.slug == "router":
+            routers[dev_name] = dev_vars
+
+        elif device.data.device_role.slug == "server":
+            servers[dev_name] = dev_vars
+
+        elif device.data.device_role.slug == "switch":
+            switches[dev_name] = dev_vars
+
+    if args.generic:
+        groups = {
+            "routers": {"hosts": routers},
+            "servers": {"hosts": servers},
+            "switches": {"hosts": switches},
+        }
+    else:
+        groups = {
+            "aethermgmt": {"hosts": routers},
+            "aethercompute": {"hosts": servers},
+            "aetherfabric": {"hosts": switches},
+        }
+
+    yaml_out = {"all": {"children": groups}}
+
+    print(yaml.safe_dump(yaml_out, indent=2))
diff --git a/scripts/nbhelper/__init__.py b/scripts/nbhelper/__init__.py
index 7755623..85acea5 100644
--- a/scripts/nbhelper/__init__.py
+++ b/scripts/nbhelper/__init__.py
@@ -1,3 +1,6 @@
+# SPDX-FileCopyrightText: © 2021 Open Networking Foundation <support@opennetworking.org>
+# SPDX-License-Identifier: Apache-2.0
+
 from .utils import initialize
 from .tenant import Tenant
 from .device import Device, VirtualMachine
diff --git a/scripts/nbhelper/container.py b/scripts/nbhelper/container.py
index 397ee32..0e728a1 100644
--- a/scripts/nbhelper/container.py
+++ b/scripts/nbhelper/container.py
@@ -1,4 +1,5 @@
 import netaddr
+from .utils import logger
 
 
 class Singleton(type):
@@ -10,7 +11,7 @@
         return cls._instances[cls]
 
 
-class Container(object):
+class Container:
     def __init__(self):
         self.instances = dict()
 
@@ -36,16 +37,19 @@
         for instance in self.instances.values():
             if "dns" in list(map(str, instance.services)):
                 return instance
+        return None
 
     def getDHCPServer(self):
         for instance in self.instances.values():
             if "tftp" in list(map(str, instance.services)):
                 return instance
+        return None
 
     def getNTPServer(self):
         for instance in self.instances.values():
             if "ntp" in list(map(str, instance.services)):
                 return instance
+        return None
 
     def getRouters(self):
         """ Get a list of Devices/VMs which type is Router """
@@ -72,6 +76,7 @@
                         prefix.subnet
                     ):
                         return str(netaddr.IPNetwork(address).ip)
+        return None
 
 
 class DeviceContainer(AssignedObjectContainer, metaclass=Singleton):
@@ -87,9 +92,6 @@
 class PrefixContainer(Container, metaclass=Singleton):
     # PrefixContainer holds all prefixes fetch from Netbox, prefix(str) as key
 
-    def get(self, instance_id, name_segments=1):
-        return super().get(instance_id)
-
     def all(self):
         return self.instances.values()
 
@@ -221,7 +223,8 @@
                             #         "eno1": {
                             #             "mgmtOnly": False,
                             #             "macaddr": "ca:fe:ba:be:11:11",
-                            #             "ipaddr": [IPAddress("10.32.4.129"), IPAddress("10.32.4.130")]
+                            #             "ipaddr": [IPAddress("10.32.4.129"),
+                            #                        IPAddress("10.32.4.130")]
                             #         }
                             #    }
                             #  "mgmtswitch1": ...
@@ -242,14 +245,24 @@
                             ]
                             interfaceDict.setdefault("mgmtOnly", False)
 
-                            # Use interface["mac_address"] as the default value, but if the mac_address
-                            #  is None, that means we are dealing with a virtual interfaces
-                            #  so we can get the linked interface's mac_address instead
+                            # Use interface["mac_address"] as the default value, but if the
+                            # mac_address is None, that means we are dealing with a virtual
+                            # interfaces so we can get the linked interface's mac_address instead
 
-                            interfaceDict.setdefault(
-                                "mac_address", interface["mac_address"] or
-                                device.interfaces[interface["instance"].label]["mac_address"]
-                            )
+                            try:
+                                interfaceDict.setdefault(
+                                    "mac_address",
+                                    interface["mac_address"]
+                                    or device.interfaces[interface["instance"].label][
+                                        "mac_address"
+                                    ],
+                                )
+                            except KeyError:
+                                logger.error(
+                                    "Problem with MAC address on interface %s",
+                                    interface,
+                                )
+
                             interfaceDict.setdefault("ip_addresses", list())
                             interfaceDict["ip_addresses"].append(address)
 
diff --git a/scripts/nbhelper/device.py b/scripts/nbhelper/device.py
index 94b03df..32a2075 100644
--- a/scripts/nbhelper/device.py
+++ b/scripts/nbhelper/device.py
@@ -4,12 +4,11 @@
 # SPDX-License-Identifier: Apache-2.0
 
 # device.py
-#
 
+import sys
 import netaddr
 
-from .utils import logger, clean_name_dns
-from .network import Prefix
+from .utils import logger
 from .container import DeviceContainer, VirtualMachineContainer, PrefixContainer
 
 
@@ -40,7 +39,7 @@
     objects = dict()
 
     def __init__(self, data):
-        from .utils import netboxapi, netbox_config
+        from .utils import netboxapi
 
         self.data = data
         self.nbapi = netboxapi
@@ -49,6 +48,7 @@
         self.id = self.data.id
         self.tenant = None
         self.primary_ip = None
+        self.primary_iface = None
 
         # In Netbox, we use FQDN as the Device name, but in the script,
         # we use the first segment to be the name of device.
@@ -108,8 +108,12 @@
             # ipam.ip_addresses doesn't have primary tag,
             # the primary tag is only available is only in the Device.
             # So we need to compare address to check which one is primary ip
-            if address.address == self.primary_ip.address:
-                interface["isPrimary"] = True
+            try:
+                if address.address == self.primary_ip.address:
+                    interface["isPrimary"] = True
+                    self.primary_iface = interface
+            except AttributeError:
+                logger.error("Error with primary address for device %s", self.fullname)
 
             # mgmt_only = False is a hack for VirtualMachine type
             if self.__class__ == VirtualMachine:
@@ -181,7 +185,7 @@
                 self.netplan_config["ethernets"].setdefault(intfName, {})
                 self.netplan_config["ethernets"][intfName].setdefault(
                     "addresses", []
-                ).append(address)
+                ).extend(interface["addresses"])
 
         # If the current selected device is a Server
         elif isinstance(self, Device) and self.data.device_role.name == "Server":
@@ -233,7 +237,9 @@
                     for dest_addr in destination.split(","):
 
                         # If interface address is in destination subnet, we don't need this route
-                        if netaddr.IPNetwork(address).ip in netaddr.IPNetwork(dest_addr):
+                        if netaddr.IPNetwork(address).ip in netaddr.IPNetwork(
+                            dest_addr
+                        ):
                             continue
 
                         new_route = {
@@ -298,7 +304,8 @@
                 }
             )
 
-        # Only management server needs to be configured the whitelist netrange of internal interface
+        # Only management server needs to be configured the whitelist netrange of
+        # internal interface
         if self.data.device_role.name == "Router":
 
             ret["interface_subnets"] = dict()
@@ -329,8 +336,13 @@
                         if prefix.subnet not in ret["interface_subnets"][intfName]:
                             ret["interface_subnets"][intfName].append(prefix.subnet)
                         for neighbor in prefix.neighbor:
-                            if neighbor.subnet not in ret["interface_subnets"][intfName]:
-                                ret["interface_subnets"][intfName].append(neighbor.subnet)
+                            if (
+                                neighbor.subnet
+                                not in ret["interface_subnets"][intfName]
+                            ):
+                                ret["interface_subnets"][intfName].append(
+                                    neighbor.subnet
+                                )
 
             for prefix in PrefixContainer().all():
 
@@ -361,8 +373,6 @@
         if self.extra_config:
             return self.extra_config
 
-        primary_ip = self.data.primary_ip.address if self.data.primary_ip else None
-
         service_names = list(map(lambda x: x.name, self.services))
 
         if "dns" in service_names:
diff --git a/scripts/nbhelper/network.py b/scripts/nbhelper/network.py
index 3a51219..9b5d824 100644
--- a/scripts/nbhelper/network.py
+++ b/scripts/nbhelper/network.py
@@ -10,7 +10,6 @@
 
 from .utils import logger, check_name_dns
 from .container import PrefixContainer
-from .container import DeviceContainer, VirtualMachineContainer
 
 
 class Prefix:
@@ -71,7 +70,6 @@
                     if self not in prefix.neighbor:
                         prefix.neighbor.append(self)
 
-
     def build_prefix(self):
         """
         find ip information for items (devices/vms, reserved_ips, dhcp_range) in prefix
diff --git a/scripts/nbhelper/service.py b/scripts/nbhelper/service.py
index 1ad992c..fe78a9f 100644
--- a/scripts/nbhelper/service.py
+++ b/scripts/nbhelper/service.py
@@ -4,12 +4,9 @@
 # SPDX-License-Identifier: Apache-2.0
 
 # service.py
-#
 
-import re
 import netaddr
 
-from .utils import logger, AttrDict
 from .container import ServiceInfoContainer
 
 
@@ -66,7 +63,7 @@
             for host in domain["hosts"]:
                 if ip_address == host["ip_addr"]:
                     return f"{host['name']}.{domainName}."
-
+        return ""
 
     dnsForwardZoneConfigs = dict()
 
@@ -91,7 +88,9 @@
         if ntpServer:
             forwardZoneConfig["cname"]["ntp"] = getDomainNameByIP(ntpServer["address"])
         if dhcpServer:
-            forwardZoneConfig["cname"]["tftp"] = getDomainNameByIP(dhcpServer["address"])
+            forwardZoneConfig["cname"]["tftp"] = getDomainNameByIP(
+                dhcpServer["address"]
+            )
         if dnsServer:
             forwardZoneConfig["cname"]["ns"] = getDomainNameByIP(dnsServer["address"])
             forwardZoneConfig["ns"].append(getDomainNameByIP(dnsServer["address"]))
@@ -126,7 +125,7 @@
         if o1 == 10:
             o2 = o3 = o4 = 0
             cidr_plen = 8
-        elif (o1 == 172 and o2 >= 16 and o2 <= 31) or (o1 == 192 and o2 == 168):
+        elif (o1 == 172 and 16 <= o2 <= 31) or (o1 == 192 and o2 == 168):
             o3 = o4 = 0
             cidr_plen = 16
 
diff --git a/scripts/nbhelper/tenant.py b/scripts/nbhelper/tenant.py
index 4d529a7..a4d4048 100644
--- a/scripts/nbhelper/tenant.py
+++ b/scripts/nbhelper/tenant.py
@@ -6,7 +6,9 @@
 # tenant.py
 # The tenant abstract object of Netbox Object - Tenant
 
-from .utils import logger, netboxapi
+import sys
+
+from .utils import logger
 from .device import Device, VirtualMachine
 from .network import Prefix
 
@@ -58,9 +60,9 @@
         """
 
         for machine in self.devices + self.vms:
-            if name and machine.name == name:
-                return machine
-            elif machine.data["device_role"]["name"] == "Router":
+            if (name and machine.name == name) or machine.data["device_role"][
+                "name"
+            ] == "Router":
                 return machine
 
         ret_msg = (
@@ -71,10 +73,12 @@
         logger.error(ret_msg, name)
         sys.exit(1)
 
-    def get_devices(self, device_types=["server", "router"]):
+    def get_devices(self, device_types=None):
         """
         Get all devices (Router + Server) belong to this Tenant
         """
+        if not device_types:
+            device_types = ["server", "router"]
 
         if not device_types:
             return self.devices + self.vms
diff --git a/scripts/nbhelper/utils.py b/scripts/nbhelper/utils.py
index 5614ba9..d44bc96 100644
--- a/scripts/nbhelper/utils.py
+++ b/scripts/nbhelper/utils.py
@@ -6,11 +6,13 @@
 # utils.py
 # The utility functions shared among nbhelper objects
 
-import re
-import logging
 import argparse
-import pynetbox
+import logging
+import re
+import sys
+
 import requests
+import pynetbox
 
 from ruamel import yaml
 
@@ -36,7 +38,7 @@
 
     for require_args in ["api_endpoint", "token", "tenant_name"]:
         if not netbox_config.get(require_args):
-            logger.error("The require argument: %s was not set. Stop." % require_args)
+            logger.error("The require argument: %s was not set. Stop.", require_args)
             sys.exit(1)
 
     netboxapi = pynetbox.api(
@@ -53,7 +55,7 @@
     return args
 
 
-def parse_cli_args(extra_args={}):
+def parse_cli_args(extra_args):
     """
     parse CLI arguments.  Can add extra arguments with a option:kwargs dict
     """
@@ -115,5 +117,5 @@
 
 class AttrDict(dict):
     def __init__(self, *args, **kwargs):
-        super(AttrDict, self).__init__(*args, **kwargs)
+        super().__init__(*args, **kwargs)
         self.__dict__ = self
diff --git a/scripts/netbox_hosts.py b/scripts/netbox_hosts.py
deleted file mode 100644
index e968e8e..0000000
--- a/scripts/netbox_hosts.py
+++ /dev/null
@@ -1,432 +0,0 @@
-#!/usr/bin/env python3
-
-# SPDX-FileCopyrightText: © 2020 Open Networking Foundation <support@opennetworking.org>
-# SPDX-License-Identifier: Apache-2.0
-
-# TODO:
-#  Fix issues where IPMI given primary IP for a node
-
-from __future__ import absolute_import
-
-import argparse
-import json
-import logging
-import netaddr
-import re
-import ssl
-import urllib.parse
-import urllib.request
-from ruamel import yaml
-
-# create shared logger
-logging.basicConfig()
-logger = logging.getLogger("nbht")
-
-# global dict of jsonpath expressions -> compiled jsonpath parsers, as
-# reparsing expressions in each loop results in 100x longer execution time
-jpathexpr = {}
-
-# headers to pass, set globally
-headers = []
-
-# settings
-settings = {}
-
-# cached data from API
-devices = {}
-interfaces = {}
-
-
-def parse_nb_args():
-    """
-    parse CLI arguments
-    """
-
-    parser = argparse.ArgumentParser(description="NetBox Host Descriptions")
-
-    # Positional args
-    parser.add_argument(
-        "settings",
-        type=argparse.FileType("r"),
-        help="YAML ansible inventory file w/netbox info",
-    )
-
-    parser.add_argument(
-        "--debug", action="store_true", help="Print additional debugging information"
-    )
-
-    return parser.parse_args()
-
-
-def json_api_get(
-    url,
-    headers,
-    data=None,
-    trim_prefix=False,
-    allow_failure=False,
-    validate_certs=False,
-):
-    """
-    Call JSON API endpoint, return data as a dict
-    """
-
-    logger.debug("json_api_get url: %s", url)
-
-    # if data included, encode it as JSON
-    if data:
-        data_enc = str(json.dumps(data)).encode("utf-8")
-
-        request = urllib.request.Request(url, data=data_enc, method="POST")
-        request.add_header("Content-Type", "application/json; charset=UTF-8")
-    else:
-        request = urllib.request.Request(url)
-
-    # add headers tuples
-    for header in headers:
-        request.add_header(*header)
-
-    try:
-
-        if validate_certs:
-            response = urllib.request.urlopen(request)
-
-        else:
-            ctx = ssl.create_default_context()
-            ctx.check_hostname = False
-            ctx.verify_mode = ssl.CERT_NONE
-
-            response = urllib.request.urlopen(request, context=ctx)
-
-    except urllib.error.HTTPError:
-        # asking for data that doesn't exist results in a 404, just return nothing
-        if allow_failure:
-            return None
-        logger.exception("Server encountered an HTTPError at URL: '%s'", url)
-    except urllib.error.URLError:
-        logger.exception("An URLError occurred at URL: '%s'", url)
-    else:
-        # docs: https://docs.python.org/3/library/json.html
-        jsondata = response.read()
-        logger.debug("API response: %s", jsondata)
-
-    try:
-        data = json.loads(jsondata)
-    except json.decoder.JSONDecodeError:
-        # allow return of no data
-        if allow_failure:
-            return None
-        logger.exception("Unable to decode JSON")
-    else:
-        logger.debug("JSON decoded: %s", data)
-
-    return data
-
-
-def create_dns_zone(extension, devs):
-    # Checks for dns entries
-
-    a_recs = {}  # PTR records created by inverting this
-    cname_recs = {}
-    srv_recs = {}
-    ns_recs = []
-    txt_recs = {}
-
-    # scan through devs and look for dns_name, if not, make from name and
-    # extension
-    for name, value in devs.items():
-
-        # add DNS entries for every DHCP host if there's a DHCP range
-        # DHCP addresses are of the form dhcp###.extension
-        if name == "prefix_dhcp":
-            for ip in netaddr.IPNetwork(value["dhcp_range"]).iter_hosts():
-                a_recs["dhcp%03d" % (ip.words[3])] = str(ip)
-
-            continue
-
-        # require DNS names to only use ASCII characters
-        # (alphanumeric, lowercase, with dash/period)
-        # _'s are used in SRV/TXT records, but in general use aren't recommended
-        dns_name = re.sub("[^a-z0-9.-]", "-", name.lower(), 0, re.ASCII)
-
-        # Add as an A record (and inverse, PTR record), only if it's a new name
-        if dns_name not in a_recs:
-            a_recs[dns_name] = value["ip4"]
-        else:
-            # most likely a data entry error
-            logger.warning(
-                "Duplicate DNS name '%s' for devices at IP: '%s' and '%s', ignoring",
-                dns_name,
-                a_recs[dns_name],
-                value["ip4"],
-            )
-            continue
-
-        # if a DNS name is given as a part of the IP address, it's viewed as a CNAME
-        if value["dns_name"]:
-
-            if re.search("%s$" % extension, value["dns_name"]):
-
-                # strip off the extension, and add as a CNAME
-                dns_cname = value["dns_name"].split(".%s" % extension)[0]
-
-            elif "." in value["dns_name"]:
-                logger.warning(
-                    "Device '%s' has a IP assigned DNS name '%s' outside "
-                    + "the prefix extension: '%s', ignoring",
-                    name,
-                    value["dns_name"],
-                    extension,
-                )
-                continue
-
-            else:
-                dns_cname = value["dns_name"]
-
-            if dns_cname == dns_name:
-                logger.warning(
-                    "DNS Name field '%s' is identical to device name '%s', ignoring",
-                    value["dns_name"],
-                    dns_name,
-                )
-            else:
-                cname_recs[dns_cname] = "%s.%s." % (dns_name, extension)
-
-        # Add services as cnames, and possibly ns records
-        for svc in value["services"]:
-
-            # only add service if it uses the IP of the host
-            if value["ip4"] in svc["ip4s"]:
-                cname_recs[svc["name"]] = "%s.%s." % (dns_name, extension)
-
-            if svc["port"] == 53 and svc["protocol"] == "udp":
-                ns_recs.append("%s.%s." % (dns_name, extension))
-
-    return {
-        "a": a_recs,
-        "cname": cname_recs,
-        "ns": ns_recs,
-        "srv": srv_recs,
-        "txt": txt_recs,
-    }
-
-
-def create_dhcp_subnet(devs):
-    # makes DHCP subnet information
-
-    hosts = {}
-
-    for name, value in devs.items():
-
-        # has a MAC address, and it's not null
-        if "macaddr" in value and value["macaddr"]:
-
-            hosts[value["ip4"]] = {
-                "name": name,
-                "macaddr": value["macaddr"],
-            }
-
-    return hosts
-
-
-def get_device_services(device_id, filters=""):
-
-    # get services info
-    url = "%s%s" % (
-        settings["api_endpoint"],
-        "api/ipam/services/?device_id=%s%s" % (device_id, filters),
-    )
-
-    raw_svcs = json_api_get(url, headers, validate_certs=settings["validate_certs"])
-
-    services = []
-
-    for rsvc in raw_svcs["results"]:
-
-        svc = {}
-
-        svc["name"] = rsvc["name"]
-        svc["description"] = rsvc["description"]
-        svc["port"] = rsvc["port"]
-        svc["protocol"] = rsvc["protocol"]["value"]
-        svc["ip4s"] = []
-
-        for ip in rsvc["ipaddresses"]:
-            svc["ip4s"].append(str(netaddr.IPNetwork(ip["address"]).ip))
-
-        services.append(svc)
-
-    return services
-
-
-def get_interface_mac_addr(interface_id):
-    # return a mac addres, or None if undefined
-
-    # get the interface info
-    url = "%s%s" % (settings["api_endpoint"], "api/dcim/interfaces/%s/" % interface_id)
-
-    iface = json_api_get(url, headers, validate_certs=settings["validate_certs"])
-
-    if iface["mac_address"]:
-        return iface["mac_address"]
-
-    return None
-
-
-def get_device_interfaces(device_id, filters=""):
-
-    url = "%s%s" % (
-        settings["api_endpoint"],
-        "api/dcim/interfaces/?device_id=%s%s" % (device_id, filters),
-    )
-
-    logger.debug("raw_ifaces_url: %s", url)
-
-    raw_ifaces = json_api_get(url, headers, validate_certs=settings["validate_certs"])
-
-    logger.debug("raw_ifaces: %s", raw_ifaces)
-
-    ifaces = []
-
-    for raw_iface in raw_ifaces["results"]:
-
-        iface = {}
-
-        iface["name"] = raw_iface["name"]
-        iface["macaddr"] = raw_iface["mac_address"]
-        iface["mgmt_only"] = raw_iface["mgmt_only"]
-        iface["description"] = raw_iface["description"]
-
-        if raw_iface["count_ipaddresses"]:
-            url = "%s%s" % (
-                settings["api_endpoint"],
-                "api/ipam/ip-addresses/?interface_id=%s" % raw_iface["id"],
-            )
-
-            raw_ip = json_api_get(
-                url, headers, validate_certs=settings["validate_certs"]
-            )
-
-            iface["ip4"] = str(netaddr.IPNetwork(raw_ip["results"][0]["address"]).ip)
-
-        ifaces.append(iface)
-
-    return ifaces
-
-
-def get_prefix_devices(prefix, filters=""):
-
-    # get all devices in a prefix
-    url = "%s%s" % (
-        settings["api_endpoint"],
-        "api/ipam/ip-addresses/?parent=%s%s" % (prefix, filters),
-    )
-
-    raw_ips = json_api_get(url, headers, validate_certs=settings["validate_certs"])
-
-    logger.debug("raw_ips: %s", raw_ips)
-
-    devs = {}
-
-    for ip in raw_ips["results"]:
-
-        logger.info("ip: %s", ip)
-
-        # if it's a DHCP range, add that range to the dev list as prefix_dhcp
-        if ip["status"]["value"] == "dhcp":
-            devs["prefix_dhcp"] = {"dhcp_range": ip["address"]}
-            continue
-
-        dev = {}
-
-        dev["ip4"] = str(netaddr.IPNetwork(ip["address"]).ip)
-        dev["macaddr"] = get_interface_mac_addr(ip["assigned_object"]["id"])
-
-        ifaces = get_device_interfaces(
-            ip["assigned_object"]["device"]["id"], "&mgmt_only=true"
-        )
-
-        if ifaces and dev["ip4"] == ifaces[0]["ip4"]:  # this is a mgmt IP
-            devname = "%s-%s" % (
-                ip["assigned_object"]["device"]["name"],
-                ifaces[0]["name"],
-            )
-            dev["dns_name"] = ""
-            dev["services"] = []
-
-        else:  # this is a primary IP
-
-            devname = ip["assigned_object"]["device"]["name"]
-            dev["dns_name"] = ip["dns_name"] if "dns_name" in ip else "None"
-            dev["services"] = get_device_services(ip["assigned_object"]["device"]["id"])
-
-        devs[devname] = dev
-
-    return devs
-
-
-def get_prefix_data(prefix):
-
-    # get all devices in a prefix
-    url = "%s%s" % (settings["api_endpoint"], "api/ipam/prefixes/?prefix=%s" % prefix)
-
-    raw_prefix = json_api_get(url, headers, validate_certs=settings["validate_certs"])
-
-    logger.debug("raw_prefix: %s", raw_prefix)
-
-    return raw_prefix["results"][0]
-
-
-# main function that calls other functions
-if __name__ == "__main__":
-
-    args = parse_nb_args()
-
-    # only print log messages if debugging
-    if args.debug:
-        logger.setLevel(logging.DEBUG)
-    else:
-        logger.setLevel(logging.INFO)
-
-    # load settings from yaml file
-    settings = yaml.safe_load(args.settings.read())
-
-    logger.info("settings: %s" % settings)
-
-    # global, so this isn't run multiple times
-    headers = [
-        ("Authorization", "Token %s" % settings["token"]),
-    ]
-
-    # create structure from extracted data
-
-    dns_global = {}
-    dns_zones = {}
-    dhcp_global = {}
-    dhcp_subnets = {}
-
-    for prefix in settings["dns_prefixes"]:
-
-        prefix_data = get_prefix_data(prefix)
-
-        prefix_domain_extension = prefix_data["description"]
-
-        devs = get_prefix_devices(prefix)
-
-        dns_zones[prefix_domain_extension] = create_dns_zone(
-            prefix_domain_extension, devs
-        )
-
-        dns_zones[prefix_domain_extension]["ip_range"] = prefix
-
-        dhcp_subnets[prefix] = create_dhcp_subnet(devs)
-
-    yaml_out = {
-        "dns_global": dns_global,
-        "dns_zones": dns_zones,
-        "dhcp_global": dhcp_global,
-        "dhcp_subnets": dhcp_subnets,
-        "devs": devs,
-        "prefix_data": prefix_data,
-    }
-
-    print(yaml.safe_dump(yaml_out, indent=2))
diff --git a/scripts/pxeconfig.py b/scripts/pxeconfig.py
index 97aedab..fe9e1a7 100644
--- a/scripts/pxeconfig.py
+++ b/scripts/pxeconfig.py
@@ -11,7 +11,6 @@
 from __future__ import absolute_import
 
 import nbhelper
-
 from ruamel import yaml
 
 # main function that calls other functions
@@ -28,24 +27,25 @@
     }
 
     args = nbhelper.initialize(extra_args)
-    tenant = nbhelper.NBTenant()
+    tenant = nbhelper.Tenant()
 
     yaml_out = {}
     pxeboot_hosts = []
 
-    prefixes = nbhelper.NBPrefix.all_prefixes()
-    devices = nbhelper.NBDevice.all_objects()
-
-    for dev_id, device in devices.items():
+    for device in tenant.get_devices():
 
         # only pxeboot for servers
-        if device.data["device_role"]["slug"] == "server":
+        if device.data.device_role.slug in ["server", "router"]:
 
             pxe_dev = {}
-            pxe_dev["serial"] = device.data["serial"]
             pxe_dev["hostname"] = device.data["name"]
             pxe_dev["domain"] = args.domain_extension
-            pxe_dev["mac_address"] = device.primary_iface()["mac_address"].lower()
+
+            if device.data["serial"]:
+                pxe_dev["serial"] = device.data["serial"]
+
+            if device.primary_iface["mac_address"]:
+                pxe_dev["mac_address"] = device.primary_iface["mac_address"].lower()
 
             pxeboot_hosts.append(pxe_dev)
 
diff --git a/scripts/tenant_validator.py b/scripts/tenant_validator.py
index 0ce504e..56c6ed7 100644
--- a/scripts/tenant_validator.py
+++ b/scripts/tenant_validator.py
@@ -8,15 +8,15 @@
 
 from __future__ import absolute_import
 
+import argparse
+import logging
 import re
 import sys
-import yaml
-import logging
-import argparse
+
+import netaddr
 import pynetbox
 import requests
-import netaddr
-
+import yaml
 
 logging.basicConfig()
 logger = logging.getLogger("TenentValidator")
@@ -37,7 +37,7 @@
 )
 
 
-class Configuration(object):
+class Configuration:
 
     mapping_dict = {
         logging.ERROR: logger.error,
@@ -67,7 +67,7 @@
     return ("/".join(obj.url.split("/")[-4:-2]),)
 
 
-def validate_vlans(vlans=list()):
+def validate_vlans(vlans=None):
     global misconfs
 
     for vlan in vlans:
@@ -79,7 +79,7 @@
             misconfs.append(Configuration(vlan, "VLAN tenant isn't set"))
 
 
-def validate_prefixes(prefixes=list()):
+def validate_prefixes(prefixes=None):
     global misconfs
 
     tenant_dict = dict()
@@ -154,7 +154,7 @@
 
                     dhcp_range = dhcp_addr[0].address
                     ip_addrs = netboxapi.ipam.ip_addresses.filter(parent=dhcp_range)
-                    ip_addrs = list(filter(lambda ip: ip != dhcp_addr[0], ip_addrs))
+                    ip_addrs = ip_addrs.remove(dhcp_addr[0])
                     if ip_addrs:
                         misconfs.append(
                             Configuration(
@@ -165,7 +165,7 @@
                         )
 
 
-def validate_ip_addresses(ip_addresses=list()):
+def validate_ip_addresses(ip_addresses=None):
     global misconfs
     prefix_dict = dict()
 
@@ -187,7 +187,7 @@
                     )
 
 
-def validate_interfaces(interfaces=list()):
+def validate_interfaces(interfaces=None):
     global misconfs
 
     for interface in interfaces:
@@ -233,7 +233,7 @@
                 )
 
 
-def validate_vrfs(vrfs=list()):
+def validate_vrfs(vrfs=None):
     global misconfs
 
     for vrf in vrfs:
@@ -246,7 +246,7 @@
             misconfs.append(Configuration(vrf, "VRF doesn't have tenant set"))
 
 
-def validate_machines(machines=list()):
+def validate_machines(machines=None):
     global misconfs
 
     tenant_info = dict()
@@ -298,7 +298,7 @@
             )
 
 
-def validate_tenants(tenants=list()):
+def validate_tenants(tenants=None):
     global misconfs
 
     for tenant in tenants:
@@ -322,7 +322,7 @@
 
     tenants = list(netboxapi.tenancy.tenants.filter(name=tenant_name))
     if len(tenants) == 0:
-        logger.critical("Tenant name %s wasn't found in Netbox" % tenant_name)
+        logger.critical("Tenant name %s wasn't found in Netbox", tenant_name)
         sys.exit(1)
     tenant_id = None if len(tenants) != 1 else tenants[0].id