sysconfig: refactor sysconfig to accept distro specific templates paths

Multiple distros use sysconfig format but have different content
and paths to certain files.  Update distros to specify these
template paths in their renderer_configs dictionary.

12 files changed, 1029 insertions, 635 deletions

diff --git a/cloudinit/cmd/devel/net_convert.py b/cloudinit/cmd/devel/net_convert.py
index 271dc5ed..a0f58a0a 100755
--- a/cloudinit/cmd/devel/net_convert.py
+++ b/cloudinit/cmd/devel/net_convert.py
@@ -10,6 +10,7 @@ import yaml
 from cloudinit.sources.helpers import openstack
 from cloudinit.sources import DataSourceAzure as azure
 
+from cloudinit import distros
 from cloudinit.net import eni, netplan, network_state, sysconfig
 from cloudinit import log
 
@@ -36,6 +37,11 @@ def get_parser(parser=None):
                         metavar="PATH",
                         help="directory to place output in",
                         required=True)
+    parser.add_argument("-D", "--distro",
+                        choices=[item for sublist in
+                                 distros.OSFAMILIES.values()
+                                 for item in sublist],
+                        required=True)
     parser.add_argument("-m", "--mac",
                         metavar="name,mac",
                         action='append',
@@ -96,14 +102,20 @@ def handle_args(name, args):
         sys.stderr.write('\n'.join([
             "", "Internal State",
             yaml.dump(ns, default_flow_style=False, indent=4), ""]))
+    distro_cls = distros.fetch(args.distro)
+    distro = distro_cls(args.distro, {}, None)
+    config = {}
     if args.output_kind == "eni":
         r_cls = eni.Renderer
+        config = distro.renderer_configs.get('eni')
     elif args.output_kind == "netplan":
         r_cls = netplan.Renderer
+        config = distro.renderer_configs.get('netplan')
     else:
         r_cls = sysconfig.Renderer
+        config = distro.renderer_configs.get('sysconfig')
 
-    r = r_cls()
+    r = r_cls(config=config)
     sys.stderr.write(''.join([
         "Read input format '%s' from '%s'.\n" % (
             args.kind, args.network_data.name),
diff --git a/cloudinit/distros/__init__.py b/cloudinit/distros/__init__.py
index fde054e9..d9101ce6 100755
--- a/cloudinit/distros/__init__.py
+++ b/cloudinit/distros/__init__.py
@@ -91,7 +91,7 @@ class Distro(object):
         LOG.debug("Selected renderer '%s' from priority list: %s",
                   name, priority)
         renderer = render_cls(config=self.renderer_configs.get(name))
-        renderer.render_network_config(network_config=network_config)
+        renderer.render_network_config(network_config)
         return []
 
     def _find_tz_file(self, tz):
diff --git a/cloudinit/distros/opensuse.py b/cloudinit/distros/opensuse.py
index 9f90e95e..1fe896aa 100644
--- a/cloudinit/distros/opensuse.py
+++ b/cloudinit/distros/opensuse.py
@@ -28,13 +28,23 @@ class Distro(distros.Distro):
     hostname_conf_fn = '/etc/HOSTNAME'
     init_cmd = ['service']
     locale_conf_fn = '/etc/sysconfig/language'
-    network_conf_fn = '/etc/sysconfig/network'
+    network_conf_fn = '/etc/sysconfig/network/config'
     network_script_tpl = '/etc/sysconfig/network/ifcfg-%s'
     resolve_conf_fn = '/etc/resolv.conf'
     route_conf_tpl = '/etc/sysconfig/network/ifroute-%s'
     systemd_hostname_conf_fn = '/etc/hostname'
     systemd_locale_conf_fn = '/etc/locale.conf'
     tz_local_fn = '/etc/localtime'
+    renderer_configs = {
+        'sysconfig': {
+            'control': 'etc/sysconfig/network/config',
+            'iface_templates': '%(base)s/network/ifcfg-%(name)s',
+            'route_templates': {
+                'ipv4': '%(base)s/network/ifroute-%(name)s',
+                'ipv6': '%(base)s/network/ifroute-%(name)s',
+            }
+        }
+    }
 
     def __init__(self, name, cfg, paths):
         distros.Distro.__init__(self, name, cfg, paths)
@@ -208,6 +218,9 @@ class Distro(distros.Distro):
                                             nameservers, searchservers)
         return dev_names
 
+    def _write_network_config(self, netconfig):
+        return self._supported_write_network_config(netconfig)
+
     @property
     def preferred_ntp_clients(self):
         """The preferred ntp client is dependent on the version."""
diff --git a/cloudinit/distros/rhel.py b/cloudinit/distros/rhel.py
index 1fecb619..ff513438 100644
--- a/cloudinit/distros/rhel.py
+++ b/cloudinit/distros/rhel.py
@@ -39,6 +39,16 @@ class Distro(distros.Distro):
     resolve_conf_fn = "/etc/resolv.conf"
     tz_local_fn = "/etc/localtime"
     usr_lib_exec = "/usr/libexec"
+    renderer_configs = {
+        'sysconfig': {
+            'control': 'etc/sysconfig/network',
+            'iface_templates': '%(base)s/network-scripts/ifcfg-%(name)s',
+            'route_templates': {
+                'ipv4': '%(base)s/network-scripts/route-%(name)s',
+                'ipv6': '%(base)s/network-scripts/route6-%(name)s'
+            }
+        }
+    }
 
     def __init__(self, name, cfg, paths):
         distros.Distro.__init__(self, name, cfg, paths)
diff --git a/cloudinit/net/eni.py b/cloudinit/net/eni.py
index 80be2429..c6f631a9 100644
--- a/cloudinit/net/eni.py
+++ b/cloudinit/net/eni.py
@@ -480,7 +480,7 @@ class Renderer(renderer.Renderer):
 
         return '\n\n'.join(['\n'.join(s) for s in sections]) + "\n"
 
-    def render_network_state(self, network_state, target=None):
+    def render_network_state(self, network_state, templates=None, target=None):
         fpeni = util.target_path(target, self.eni_path)
         util.ensure_dir(os.path.dirname(fpeni))
         header = self.eni_header if self.eni_header else ""
diff --git a/cloudinit/net/netplan.py b/cloudinit/net/netplan.py
index 6352e78c..bc1087f9 100644
--- a/cloudinit/net/netplan.py
+++ b/cloudinit/net/netplan.py
@@ -189,7 +189,7 @@ class Renderer(renderer.Renderer):
         self._postcmds = config.get('postcmds', False)
         self.clean_default = config.get('clean_default', True)
 
-    def render_network_state(self, network_state, target):
+    def render_network_state(self, network_state, templates=None, target=None):
         # check network state for version
         # if v2, then extract network_state.config
         # else render_v2_from_state
diff --git a/cloudinit/net/renderer.py b/cloudinit/net/renderer.py
index 57652e27..5f32e90f 100644
--- a/cloudinit/net/renderer.py
+++ b/cloudinit/net/renderer.py
@@ -45,11 +45,14 @@ class Renderer(object):
         return content.getvalue()
 
     @abc.abstractmethod
-    def render_network_state(self, network_state, target=None):
+    def render_network_state(self, network_state, templates=None,
+                             target=None):
         """Render network state."""
 
-    def render_network_config(self, network_config, target=None):
+    def render_network_config(self, network_config, templates=None,
+                              target=None):
         return self.render_network_state(
-            network_state=parse_net_config_data(network_config), target=target)
+            network_state=parse_net_config_data(network_config),
+            templates=templates, target=target)
 
 # vi: ts=4 expandtab
diff --git a/cloudinit/net/sysconfig.py b/cloudinit/net/sysconfig.py
index 3d719238..66e970e0 100644
--- a/cloudinit/net/sysconfig.py
+++ b/cloudinit/net/sysconfig.py
@@ -91,19 +91,20 @@ class ConfigMap(object):
 class Route(ConfigMap):
     """Represents a route configuration."""
 
-    route_fn_tpl_ipv4 = '%(base)s/network-scripts/route-%(name)s'
-    route_fn_tpl_ipv6 = '%(base)s/network-scripts/route6-%(name)s'
-
-    def __init__(self, route_name, base_sysconf_dir):
+    def __init__(self, route_name, base_sysconf_dir,
+                 ipv4_tpl, ipv6_tpl):
         super(Route, self).__init__()
         self.last_idx = 1
         self.has_set_default_ipv4 = False
         self.has_set_default_ipv6 = False
         self._route_name = route_name
         self._base_sysconf_dir = base_sysconf_dir
+        self.route_fn_tpl_ipv4 = ipv4_tpl
+        self.route_fn_tpl_ipv6 = ipv6_tpl
 
     def copy(self):
-        r = Route(self._route_name, self._base_sysconf_dir)
+        r = Route(self._route_name, self._base_sysconf_dir,
+                  self.route_fn_tpl_ipv4, self.route_fn_tpl_ipv6)
         r._conf = self._conf.copy()
         r.last_idx = self.last_idx
         r.has_set_default_ipv4 = self.has_set_default_ipv4
@@ -169,18 +170,22 @@ class Route(ConfigMap):
 class NetInterface(ConfigMap):
     """Represents a sysconfig/networking-script (and its config + children)."""
 
-    iface_fn_tpl = '%(base)s/network-scripts/ifcfg-%(name)s'
-
     iface_types = {
         'ethernet': 'Ethernet',
         'bond': 'Bond',
         'bridge': 'Bridge',
     }
 
-    def __init__(self, iface_name, base_sysconf_dir, kind='ethernet'):
+    def __init__(self, iface_name, base_sysconf_dir, templates,
+                 kind='ethernet'):
         super(NetInterface, self).__init__()
         self.children = []
-        self.routes = Route(iface_name, base_sysconf_dir)
+        self.templates = templates
+        route_tpl = self.templates.get('route_templates')
+        self.routes = Route(iface_name, base_sysconf_dir,
+                            ipv4_tpl=route_tpl.get('ipv4'),
+                            ipv6_tpl=route_tpl.get('ipv6'))
+        self.iface_fn_tpl = self.templates.get('iface_templates')
         self.kind = kind
 
         self._iface_name = iface_name
@@ -213,7 +218,8 @@ class NetInterface(ConfigMap):
                                      'name': self.name})
 
     def copy(self, copy_children=False, copy_routes=False):
-        c = NetInterface(self.name, self._base_sysconf_dir, kind=self._kind)
+        c = NetInterface(self.name, self._base_sysconf_dir,
+                         self.templates, kind=self._kind)
         c._conf = self._conf.copy()
         if copy_children:
             c.children = list(self.children)
@@ -251,6 +257,8 @@ class Renderer(renderer.Renderer):
         ('bridge_bridgeprio', 'PRIO'),
     ])
 
+    templates = {}
+
     def __init__(self, config=None):
         if not config:
             config = {}
@@ -261,6 +269,11 @@ class Renderer(renderer.Renderer):
         nm_conf_path = 'etc/NetworkManager/conf.d/99-cloud-init.conf'
         self.networkmanager_conf_path = config.get('networkmanager_conf_path',
                                                    nm_conf_path)
+        self.templates = {
+            'control': config.get('control'),
+            'iface_templates': config.get('iface_templates'),
+            'route_templates': config.get('route_templates'),
+        }
 
     @classmethod
     def _render_iface_shared(cls, iface, iface_cfg):
@@ -512,7 +525,7 @@ class Renderer(renderer.Renderer):
         return content_str
 
     @staticmethod
-    def _render_networkmanager_conf(network_state):
+    def _render_networkmanager_conf(network_state, templates=None):
         content = networkmanager_conf.NetworkManagerConf("")
 
         # If DNS server information is provided, configure
@@ -556,14 +569,17 @@ class Renderer(renderer.Renderer):
             cls._render_subnet_routes(iface_cfg, route_cfg, iface_subnets)
 
     @classmethod
-    def _render_sysconfig(cls, base_sysconf_dir, network_state):
+    def _render_sysconfig(cls, base_sysconf_dir, network_state,
+                          templates=None):
         '''Given state, return /etc/sysconfig files + contents'''
+        if not templates:
+            templates = cls.templates
         iface_contents = {}
         for iface in network_state.iter_interfaces():
             if iface['type'] == "loopback":
                 continue
             iface_name = iface['name']
-            iface_cfg = NetInterface(iface_name, base_sysconf_dir)
+            iface_cfg = NetInterface(iface_name, base_sysconf_dir, templates)
             cls._render_iface_shared(iface, iface_cfg)
             iface_contents[iface_name] = iface_cfg
         cls._render_physical_interfaces(network_state, iface_contents)
@@ -578,17 +594,21 @@ class Renderer(renderer.Renderer):
                     if iface_cfg:
                         contents[iface_cfg.path] = iface_cfg.to_string()
             if iface_cfg.routes:
-                contents[iface_cfg.routes.path_ipv4] = \
-                    iface_cfg.routes.to_string("ipv4")
-                contents[iface_cfg.routes.path_ipv6] = \
-                    iface_cfg.routes.to_string("ipv6")
+                for cpath, proto in zip([iface_cfg.routes.path_ipv4,
+                                         iface_cfg.routes.path_ipv6],
+                                        ["ipv4", "ipv6"]):
+                    if cpath not in contents:
+                        contents[cpath] = iface_cfg.routes.to_string(proto)
         return contents
 
-    def render_network_state(self, network_state, target=None):
+    def render_network_state(self, network_state, templates=None, target=None):
+        if not templates:
+            templates = self.templates
         file_mode = 0o644
         base_sysconf_dir = util.target_path(target, self.sysconf_dir)
         for path, data in self._render_sysconfig(base_sysconf_dir,
-                                                 network_state).items():
+                                                 network_state,
+                                                 templates=templates).items():
             util.write_file(path, data, file_mode)
         if self.dns_path:
             dns_path = util.target_path(target, self.dns_path)
@@ -598,7 +618,8 @@ class Renderer(renderer.Renderer):
         if self.networkmanager_conf_path:
             nm_conf_path = util.target_path(target,
                                             self.networkmanager_conf_path)
-            nm_conf_content = self._render_networkmanager_conf(network_state)
+            nm_conf_content = self._render_networkmanager_conf(network_state,
+                                                               templates)
             if nm_conf_content:
                 util.write_file(nm_conf_path, nm_conf_content, file_mode)
         if self.netrules_path:
@@ -606,13 +627,16 @@ class Renderer(renderer.Renderer):
             netrules_path = util.target_path(target, self.netrules_path)
             util.write_file(netrules_path, netrules_content, file_mode)
 
-        # always write /etc/sysconfig/network configuration
-        sysconfig_path = util.target_path(target, "etc/sysconfig/network")
-        netcfg = [_make_header(), 'NETWORKING=yes']
-        if network_state.use_ipv6:
-            netcfg.append('NETWORKING_IPV6=yes')
-            netcfg.append('IPV6_AUTOCONF=no')
-        util.write_file(sysconfig_path, "\n".join(netcfg) + "\n", file_mode)
+        sysconfig_path = util.target_path(target, templates.get('control'))
+        # Distros configuring /etc/sysconfig/network as a file e.g. Centos
+        if sysconfig_path.endswith('network'):
+            util.ensure_dir(os.path.dirname(sysconfig_path))
+            netcfg = [_make_header(), 'NETWORKING=yes']
+            if network_state.use_ipv6:
+                netcfg.append('NETWORKING_IPV6=yes')
+                netcfg.append('IPV6_AUTOCONF=no')
+            util.write_file(sysconfig_path,
+                            "\n".join(netcfg) + "\n", file_mode)
 
 
 def available(target=None):
diff --git a/cloudinit/tests/helpers.py b/cloudinit/tests/helpers.py
index de24e25d..9a21426e 100644
--- a/cloudinit/tests/helpers.py
+++ b/cloudinit/tests/helpers.py
@@ -16,9 +16,9 @@ import six
 import unittest2
 
 try:
-    from contextlib import ExitStack
+    from contextlib import ExitStack, contextmanager
 except ImportError:
-    from contextlib2 import ExitStack
+    from contextlib2 import ExitStack, contextmanager
 
 try:
     from configparser import ConfigParser
@@ -326,6 +326,13 @@ class FilesystemMockingTestCase(ResourceUsingTestCase):
         self.patchOS(root)
         return root
 
+    @contextmanager
+    def reRooted(self, root=None):
+        try:
+            yield self.reRoot(root)
+        finally:
+            self.patched_funcs.close()
+
 
 class HttprettyTestCase(CiTestCase):
     # necessary as http_proxy gets in the way of httpretty
diff --git a/tests/unittests/test_datasource/test_configdrive.py b/tests/unittests/test_datasource/test_configdrive.py
index 68400f22..7e6fcbbf 100644
--- a/tests/unittests/test_datasource/test_configdrive.py
+++ b/tests/unittests/test_datasource/test_configdrive.py
@@ -642,7 +642,7 @@ class TestConvertNetworkData(CiTestCase):
             routes)
         eni_renderer = eni.Renderer()
         eni_renderer.render_network_state(
-            network_state.parse_net_config_data(ncfg), self.tmp)
+            network_state.parse_net_config_data(ncfg), target=self.tmp)
         with open(os.path.join(self.tmp, "etc",
                                "network", "interfaces"), 'r') as f:
             eni_rendering = f.read()
@@ -664,7 +664,7 @@ class TestConvertNetworkData(CiTestCase):
         eni_renderer = eni.Renderer()
 
         eni_renderer.render_network_state(
-            network_state.parse_net_config_data(ncfg), self.tmp)
+            network_state.parse_net_config_data(ncfg), target=self.tmp)
         with open(os.path.join(self.tmp, "etc",
                                "network", "interfaces"), 'r') as f:
             eni_rendering = f.read()
@@ -695,7 +695,7 @@ class TestConvertNetworkData(CiTestCase):
                                           known_macs=KNOWN_MACS)
         eni_renderer = eni.Renderer()
         eni_renderer.render_network_state(
-            network_state.parse_net_config_data(ncfg), self.tmp)
+            network_state.parse_net_config_data(ncfg), target=self.tmp)
         with open(os.path.join(self.tmp, "etc",
                                "network", "interfaces"), 'r') as f:
             eni_rendering = f.read()
diff --git a/tests/unittests/test_distros/test_netconfig.py b/tests/unittests/test_distros/test_netconfig.py
index 7765e408..740fb76c 100644
--- a/tests/unittests/test_distros/test_netconfig.py
+++ b/tests/unittests/test_distros/test_netconfig.py
@@ -2,24 +2,19 @@
 
 import os
 from six import StringIO
-import stat
 from textwrap import dedent
 
 try:
     from unittest import mock
 except ImportError:
     import mock
-try:
-    from contextlib import ExitStack
-except ImportError:
-    from contextlib2 import ExitStack
 
 from cloudinit import distros
 from cloudinit.distros.parsers.sys_conf import SysConf
 from cloudinit import helpers
-from cloudinit.net import eni
 from cloudinit import settings
-from cloudinit.tests.helpers import FilesystemMockingTestCase
+from cloudinit.tests.helpers import (
+    FilesystemMockingTestCase, dir2dict, populate_dir)
 from cloudinit import util
 
 
@@ -82,7 +77,7 @@ V1_NET_CFG = {'config': [{'name': 'eth0',
                           'type': 'physical'}],
               'version': 1}
 
-V1_NET_CFG_OUTPUT = """
+V1_NET_CFG_OUTPUT = """\
 # This file is generated from information provided by
 # the datasource.  Changes to it will not persist across an instance.
 # To disable cloud-init's network configuration capabilities, write a file
@@ -116,7 +111,7 @@ V1_NET_CFG_IPV6 = {'config': [{'name': 'eth0',
                    'version': 1}
 
 
-V1_TO_V2_NET_CFG_OUTPUT = """
+V1_TO_V2_NET_CFG_OUTPUT = """\
 # This file is generated from information provided by
 # the datasource.  Changes to it will not persist across an instance.
 # To disable cloud-init's network configuration capabilities, write a file
@@ -145,7 +140,7 @@ V2_NET_CFG = {
 }
 
 
-V2_TO_V2_NET_CFG_OUTPUT = """
+V2_TO_V2_NET_CFG_OUTPUT = """\
 # This file is generated from information provided by
 # the datasource.  Changes to it will not persist across an instance.
 # To disable cloud-init's network configuration capabilities, write a file
@@ -176,21 +171,10 @@ class WriteBuffer(object):
         return self.buffer.getvalue()
 
 
-class TestNetCfgDistro(FilesystemMockingTestCase):
-
-    frbsd_ifout = """\
-hn0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
-        options=51b<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWTAGGING,TSO4,LRO>
-        ether 00:15:5d:4c:73:00
-        inet6 fe80::215:5dff:fe4c:7300%hn0 prefixlen 64 scopeid 0x2
-        inet 10.156.76.127 netmask 0xfffffc00 broadcast 10.156.79.255
-        nd6 options=23<PERFORMNUD,ACCEPT_RTADV,AUTO_LINKLOCAL>
-        media: Ethernet autoselect (10Gbase-T <full-duplex>)
-        status: active
-"""
+class TestNetCfgDistroBase(FilesystemMockingTestCase):
 
     def setUp(self):
-        super(TestNetCfgDistro, self).setUp()
+        super(TestNetCfgDistroBase, self).setUp()
         self.add_patch('cloudinit.util.system_is_snappy', 'm_snappy')
         self.add_patch('cloudinit.util.system_info', 'm_sysinfo')
         self.m_sysinfo.return_value = {'dist': ('Distro', '99.1', 'Codename')}
@@ -204,144 +188,6 @@ hn0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
         paths = helpers.Paths({})
         return cls(dname, cfg.get('system_info'), paths)
 
-    def test_simple_write_ub(self):
-        ub_distro = self._get_distro('ubuntu')
-        with ExitStack() as mocks:
-            write_bufs = {}
-
-            def replace_write(filename, content, mode=0o644, omode="wb"):
-                buf = WriteBuffer()
-                buf.mode = mode
-                buf.omode = omode
-                buf.write(content)
-                write_bufs[filename] = buf
-
-            mocks.enter_context(
-                mock.patch.object(util, 'write_file', replace_write))
-            mocks.enter_context(
-                mock.patch.object(os.path, 'isfile', return_value=False))
-
-            ub_distro.apply_network(BASE_NET_CFG, False)
-
-            self.assertEqual(len(write_bufs), 1)
-            eni_name = '/etc/network/interfaces.d/50-cloud-init.cfg'
-            self.assertIn(eni_name, write_bufs)
-            write_buf = write_bufs[eni_name]
-            self.assertEqual(str(write_buf).strip(), BASE_NET_CFG.strip())
-            self.assertEqual(write_buf.mode, 0o644)
-
-    def test_apply_network_config_eni_ub(self):
-        ub_distro = self._get_distro('ubuntu')
-        with ExitStack() as mocks:
-            write_bufs = {}
-
-            def replace_write(filename, content, mode=0o644, omode="wb"):
-                buf = WriteBuffer()
-                buf.mode = mode
-                buf.omode = omode
-                buf.write(content)
-                write_bufs[filename] = buf
-
-            # eni availability checks
-            mocks.enter_context(
-                mock.patch.object(util, 'which', return_value=True))
-            mocks.enter_context(
-                mock.patch.object(eni, 'available', return_value=True))
-            mocks.enter_context(
-                mock.patch.object(util, 'ensure_dir'))
-            mocks.enter_context(
-                mock.patch.object(util, 'write_file', replace_write))
-            mocks.enter_context(
-                mock.patch.object(os.path, 'isfile', return_value=False))
-            mocks.enter_context(
-                mock.patch("cloudinit.net.eni.glob.glob",
-                           return_value=[]))
-
-            ub_distro.apply_network_config(V1_NET_CFG, False)
-
-            self.assertEqual(len(write_bufs), 2)
-            eni_name = '/etc/network/interfaces.d/50-cloud-init.cfg'
-            self.assertIn(eni_name, write_bufs)
-            write_buf = write_bufs[eni_name]
-            self.assertEqual(str(write_buf).strip(), V1_NET_CFG_OUTPUT.strip())
-            self.assertEqual(write_buf.mode, 0o644)
-
-    def test_apply_network_config_v1_to_netplan_ub(self):
-        renderers = ['netplan']
-        devlist = ['eth0', 'lo']
-        ub_distro = self._get_distro('ubuntu', renderers=renderers)
-        with ExitStack() as mocks:
-            write_bufs = {}
-
-            def replace_write(filename, content, mode=0o644, omode="wb"):
-                buf = WriteBuffer()
-                buf.mode = mode
-                buf.omode = omode
-                buf.write(content)
-                write_bufs[filename] = buf
-
-            mocks.enter_context(
-                mock.patch.object(util, 'which', return_value=True))
-            mocks.enter_context(
-                mock.patch.object(util, 'write_file', replace_write))
-            mocks.enter_context(
-                mock.patch.object(util, 'ensure_dir'))
-            mocks.enter_context(
-                mock.patch.object(util, 'subp', return_value=(0, 0)))
-            mocks.enter_context(
-                mock.patch.object(os.path, 'isfile', return_value=False))
-            mocks.enter_context(
-                mock.patch("cloudinit.net.netplan.get_devicelist",
-                           return_value=devlist))
-
-            ub_distro.apply_network_config(V1_NET_CFG, False)
-
-            self.assertEqual(len(write_bufs), 1)
-            netplan_name = '/etc/netplan/50-cloud-init.yaml'
-            self.assertIn(netplan_name, write_bufs)
-            write_buf = write_bufs[netplan_name]
-            self.assertEqual(str(write_buf).strip(),
-                             V1_TO_V2_NET_CFG_OUTPUT.strip())
-            self.assertEqual(write_buf.mode, 0o644)
-
-    def test_apply_network_config_v2_passthrough_ub(self):
-        renderers = ['netplan']
-        devlist = ['eth0', 'lo']
-        ub_distro = self._get_distro('ubuntu', renderers=renderers)
-        with ExitStack() as mocks:
-            write_bufs = {}
-
-            def replace_write(filename, content, mode=0o644, omode="wb"):
-                buf = WriteBuffer()
-                buf.mode = mode
-                buf.omode = omode
-                buf.write(content)
-                write_bufs[filename] = buf
-
-            mocks.enter_context(
-                mock.patch.object(util, 'which', return_value=True))
-            mocks.enter_context(
-                mock.patch.object(util, 'write_file', replace_write))
-            mocks.enter_context(
-                mock.patch.object(util, 'ensure_dir'))
-            mocks.enter_context(
-                mock.patch.object(util, 'subp', return_value=(0, 0)))
-            mocks.enter_context(
-                mock.patch.object(os.path, 'isfile', return_value=False))
-            # FreeBSD does not have '/sys/class/net' file,
-            # so we need mock here.
-            mocks.enter_context(
-                mock.patch.object(os, 'listdir', return_value=devlist))
-            ub_distro.apply_network_config(V2_NET_CFG, False)
-
-            self.assertEqual(len(write_bufs), 1)
-            netplan_name = '/etc/netplan/50-cloud-init.yaml'
-            self.assertIn(netplan_name, write_bufs)
-            write_buf = write_bufs[netplan_name]
-            self.assertEqual(str(write_buf).strip(),
-                             V2_TO_V2_NET_CFG_OUTPUT.strip())
-            self.assertEqual(write_buf.mode, 0o644)
-
     def assertCfgEquals(self, blob1, blob2):
         b1 = dict(SysConf(blob1.strip().splitlines()))
         b2 = dict(SysConf(blob2.strip().splitlines()))
@@ -353,6 +199,20 @@ hn0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
         for (k, v) in b1.items():
             self.assertEqual(v, b2[k])
 
+
+class TestNetCfgDistroFreebsd(TestNetCfgDistroBase):
+
+    frbsd_ifout = """\
+hn0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
+        options=51b<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWTAGGING,TSO4,LRO>
+        ether 00:15:5d:4c:73:00
+        inet6 fe80::215:5dff:fe4c:7300%hn0 prefixlen 64 scopeid 0x2
+        inet 10.156.76.127 netmask 0xfffffc00 broadcast 10.156.79.255
+        nd6 options=23<PERFORMNUD,ACCEPT_RTADV,AUTO_LINKLOCAL>
+        media: Ethernet autoselect (10Gbase-T <full-duplex>)
+        status: active
+"""
+
     @mock.patch('cloudinit.distros.freebsd.Distro.get_ifconfig_list')
     @mock.patch('cloudinit.distros.freebsd.Distro.get_ifconfig_ifname_out')
     def test_get_ip_nic_freebsd(self, ifname_out, iflist):
@@ -376,349 +236,33 @@ hn0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
         res = frbsd_distro.generate_fallback_config()
         self.assertIsNotNone(res)
 
-    def test_simple_write_rh(self):
-        rh_distro = self._get_distro('rhel')
-
-        write_bufs = {}
-
-        def replace_write(filename, content, mode=0o644, omode="wb"):
-            buf = WriteBuffer()
-            buf.mode = mode
-            buf.omode = omode
-            buf.write(content)
-            write_bufs[filename] = buf
-
-        with ExitStack() as mocks:
-            mocks.enter_context(
-                mock.patch.object(util, 'write_file', replace_write))
-            mocks.enter_context(
-                mock.patch.object(util, 'load_file', return_value=''))
-            mocks.enter_context(
-                mock.patch.object(os.path, 'isfile', return_value=False))
-
-            rh_distro.apply_network(BASE_NET_CFG, False)
-
-            self.assertEqual(len(write_bufs), 4)
-            self.assertIn('/etc/sysconfig/network-scripts/ifcfg-lo',
-                          write_bufs)
-            write_buf = write_bufs['/etc/sysconfig/network-scripts/ifcfg-lo']
-            expected_buf = '''
-DEVICE="lo"
-ONBOOT=yes
-'''
-            self.assertCfgEquals(expected_buf, str(write_buf))
-            self.assertEqual(write_buf.mode, 0o644)
-
-            self.assertIn('/etc/sysconfig/network-scripts/ifcfg-eth0',
-                          write_bufs)
-            write_buf = write_bufs['/etc/sysconfig/network-scripts/ifcfg-eth0']
-            expected_buf = '''
-DEVICE="eth0"
-BOOTPROTO="static"
-NETMASK="255.255.255.0"
-IPADDR="192.168.1.5"
-ONBOOT=yes
-GATEWAY="192.168.1.254"
-BROADCAST="192.168.1.0"
-'''
-            self.assertCfgEquals(expected_buf, str(write_buf))
-            self.assertEqual(write_buf.mode, 0o644)
-
-            self.assertIn('/etc/sysconfig/network-scripts/ifcfg-eth1',
-                          write_bufs)
-            write_buf = write_bufs['/etc/sysconfig/network-scripts/ifcfg-eth1']
-            expected_buf = '''
-DEVICE="eth1"
-BOOTPROTO="dhcp"
-ONBOOT=yes
-'''
-            self.assertCfgEquals(expected_buf, str(write_buf))
-            self.assertEqual(write_buf.mode, 0o644)
-
-            self.assertIn('/etc/sysconfig/network', write_bufs)
-            write_buf = write_bufs['/etc/sysconfig/network']
-            expected_buf = '''
-# Created by cloud-init v. 0.7
-NETWORKING=yes
-'''
-            self.assertCfgEquals(expected_buf, str(write_buf))
-            self.assertEqual(write_buf.mode, 0o644)
-
-    def test_apply_network_config_rh(self):
-        renderers = ['sysconfig']
-        rh_distro = self._get_distro('rhel', renderers=renderers)
-
-        write_bufs = {}
-
-        def replace_write(filename, content, mode=0o644, omode="wb"):
-            buf = WriteBuffer()
-            buf.mode = mode
-            buf.omode = omode
-            buf.write(content)
-            write_bufs[filename] = buf
-
-        with ExitStack() as mocks:
-            # sysconfig availability checks
-            mocks.enter_context(
-                mock.patch.object(util, 'which', return_value=True))
-            mocks.enter_context(
-                mock.patch.object(util, 'write_file', replace_write))
-            mocks.enter_context(
-                mock.patch.object(util, 'load_file', return_value=''))
-            mocks.enter_context(
-                mock.patch.object(os.path, 'isfile', return_value=True))
-
-            rh_distro.apply_network_config(V1_NET_CFG, False)
-
-            self.assertEqual(len(write_bufs), 5)
-
-            # eth0
-            self.assertIn('/etc/sysconfig/network-scripts/ifcfg-eth0',
-                          write_bufs)
-            write_buf = write_bufs['/etc/sysconfig/network-scripts/ifcfg-eth0']
-            expected_buf = '''
-# Created by cloud-init on instance boot automatically, do not edit.
-#
-BOOTPROTO=none
-DEFROUTE=yes
-DEVICE=eth0
-GATEWAY=192.168.1.254
-IPADDR=192.168.1.5
-NETMASK=255.255.255.0
-NM_CONTROLLED=no
-ONBOOT=yes
-TYPE=Ethernet
-USERCTL=no
-'''
-            self.assertCfgEquals(expected_buf, str(write_buf))
-            self.assertEqual(write_buf.mode, 0o644)
-
-            # eth1
-            self.assertIn('/etc/sysconfig/network-scripts/ifcfg-eth1',
-                          write_bufs)
-            write_buf = write_bufs['/etc/sysconfig/network-scripts/ifcfg-eth1']
-            expected_buf = '''
-# Created by cloud-init on instance boot automatically, do not edit.
-#
-BOOTPROTO=dhcp
-DEVICE=eth1
-NM_CONTROLLED=no
-ONBOOT=yes
-TYPE=Ethernet
-USERCTL=no
-'''
-            self.assertCfgEquals(expected_buf, str(write_buf))
-            self.assertEqual(write_buf.mode, 0o644)
-
-            self.assertIn('/etc/sysconfig/network', write_bufs)
-            write_buf = write_bufs['/etc/sysconfig/network']
-            expected_buf = '''
-# Created by cloud-init v. 0.7
-NETWORKING=yes
-'''
-            self.assertCfgEquals(expected_buf, str(write_buf))
-            self.assertEqual(write_buf.mode, 0o644)
-
-    def test_write_ipv6_rhel(self):
-        rh_distro = self._get_distro('rhel')
-
-        write_bufs = {}
-
-        def replace_write(filename, content, mode=0o644, omode="wb"):
-            buf = WriteBuffer()
-            buf.mode = mode
-            buf.omode = omode
-            buf.write(content)
-            write_bufs[filename] = buf
-
-        with ExitStack() as mocks:
-            mocks.enter_context(
-                mock.patch.object(util, 'write_file', replace_write))
-            mocks.enter_context(
-                mock.patch.object(util, 'load_file', return_value=''))
-            mocks.enter_context(
-                mock.patch.object(os.path, 'isfile', return_value=False))
-            rh_distro.apply_network(BASE_NET_CFG_IPV6, False)
-
-            self.assertEqual(len(write_bufs), 4)
-            self.assertIn('/etc/sysconfig/network-scripts/ifcfg-lo',
-                          write_bufs)
-            write_buf = write_bufs['/etc/sysconfig/network-scripts/ifcfg-lo']
-            expected_buf = '''
-DEVICE="lo"
-ONBOOT=yes
-'''
-            self.assertCfgEquals(expected_buf, str(write_buf))
-            self.assertEqual(write_buf.mode, 0o644)
-
-            self.assertIn('/etc/sysconfig/network-scripts/ifcfg-eth0',
-                          write_bufs)
-            write_buf = write_bufs['/etc/sysconfig/network-scripts/ifcfg-eth0']
-            expected_buf = '''
-DEVICE="eth0"
-BOOTPROTO="static"
-NETMASK="255.255.255.0"
-IPADDR="192.168.1.5"
-ONBOOT=yes
-GATEWAY="192.168.1.254"
-BROADCAST="192.168.1.0"
-IPV6INIT=yes
-IPV6ADDR="2607:f0d0:1002:0011::2"
-IPV6_DEFAULTGW="2607:f0d0:1002:0011::1"
-'''
-            self.assertCfgEquals(expected_buf, str(write_buf))
-            self.assertEqual(write_buf.mode, 0o644)
-            self.assertIn('/etc/sysconfig/network-scripts/ifcfg-eth1',
-                          write_bufs)
-            write_buf = write_bufs['/etc/sysconfig/network-scripts/ifcfg-eth1']
-            expected_buf = '''
-DEVICE="eth1"
-BOOTPROTO="static"
-NETMASK="255.255.255.0"
-IPADDR="192.168.1.6"
-ONBOOT=no
-GATEWAY="192.168.1.254"
-BROADCAST="192.168.1.0"
-IPV6INIT=yes
-IPV6ADDR="2607:f0d0:1002:0011::3"
-IPV6_DEFAULTGW="2607:f0d0:1002:0011::1"
-'''
-            self.assertCfgEquals(expected_buf, str(write_buf))
-            self.assertEqual(write_buf.mode, 0o644)
-
-            self.assertIn('/etc/sysconfig/network', write_bufs)
-            write_buf = write_bufs['/etc/sysconfig/network']
-            expected_buf = '''
-# Created by cloud-init v. 0.7
-NETWORKING=yes
-NETWORKING_IPV6=yes
-IPV6_AUTOCONF=no
-'''
-            self.assertCfgEquals(expected_buf, str(write_buf))
-            self.assertEqual(write_buf.mode, 0o644)
-
-    def test_apply_network_config_ipv6_rh(self):
-        renderers = ['sysconfig']
-        rh_distro = self._get_distro('rhel', renderers=renderers)
-
-        write_bufs = {}
-
-        def replace_write(filename, content, mode=0o644, omode="wb"):
-            buf = WriteBuffer()
-            buf.mode = mode
-            buf.omode = omode
-            buf.write(content)
-            write_bufs[filename] = buf
-
-        with ExitStack() as mocks:
-            mocks.enter_context(
-                mock.patch.object(util, 'which', return_value=True))
-            mocks.enter_context(
-                mock.patch.object(util, 'write_file', replace_write))
-            mocks.enter_context(
-                mock.patch.object(util, 'load_file', return_value=''))
-            mocks.enter_context(
-                mock.patch.object(os.path, 'isfile', return_value=True))
-
-            rh_distro.apply_network_config(V1_NET_CFG_IPV6, False)
-
-            self.assertEqual(len(write_bufs), 5)
-
-            self.assertIn('/etc/sysconfig/network-scripts/ifcfg-eth0',
-                          write_bufs)
-            write_buf = write_bufs['/etc/sysconfig/network-scripts/ifcfg-eth0']
-            expected_buf = '''
-# Created by cloud-init on instance boot automatically, do not edit.
-#
-BOOTPROTO=none
-DEFROUTE=yes
-DEVICE=eth0
-IPV6ADDR=2607:f0d0:1002:0011::2/64
-IPV6INIT=yes
-IPV6_DEFAULTGW=2607:f0d0:1002:0011::1
-NM_CONTROLLED=no
-ONBOOT=yes
-TYPE=Ethernet
-USERCTL=no
-'''
-            self.assertCfgEquals(expected_buf, str(write_buf))
-            self.assertEqual(write_buf.mode, 0o644)
-            self.assertIn('/etc/sysconfig/network-scripts/ifcfg-eth1',
-                          write_bufs)
-            write_buf = write_bufs['/etc/sysconfig/network-scripts/ifcfg-eth1']
-            expected_buf = '''
-# Created by cloud-init on instance boot automatically, do not edit.
-#
-BOOTPROTO=dhcp
-DEVICE=eth1
-NM_CONTROLLED=no
-ONBOOT=yes
-TYPE=Ethernet
-USERCTL=no
-'''
-            self.assertCfgEquals(expected_buf, str(write_buf))
-            self.assertEqual(write_buf.mode, 0o644)
-
-            self.assertIn('/etc/sysconfig/network', write_bufs)
-            write_buf = write_bufs['/etc/sysconfig/network']
-            expected_buf = '''
-# Created by cloud-init v. 0.7
-NETWORKING=yes
-NETWORKING_IPV6=yes
-IPV6_AUTOCONF=no
-'''
-            self.assertCfgEquals(expected_buf, str(write_buf))
-            self.assertEqual(write_buf.mode, 0o644)
-
     def test_simple_write_freebsd(self):
         fbsd_distro = self._get_distro('freebsd')
 
-        write_bufs = {}
+        rc_conf = '/etc/rc.conf'
         read_bufs = {
-            '/etc/rc.conf': '',
-            '/etc/resolv.conf': '',
+            rc_conf: 'initial-rc-conf-not-validated',
+            '/etc/resolv.conf': 'initial-resolv-conf-not-validated',
         }
 
-        def replace_write(filename, content, mode=0o644, omode="wb"):
-            buf = WriteBuffer()
-            buf.mode = mode
-            buf.omode = omode
-            buf.write(content)
-            write_bufs[filename] = buf
-
-        def replace_read(fname, read_cb=None, quiet=False):
-            if fname not in read_bufs:
-                if fname in write_bufs:
-                    return str(write_bufs[fname])
-                raise IOError("%s not found" % fname)
-            else:
-                if fname in write_bufs:
-                    return str(write_bufs[fname])
-                return read_bufs[fname]
-
-        with ExitStack() as mocks:
-            mocks.enter_context(
-                mock.patch.object(util, 'subp', return_value=('vtnet0', '')))
-            mocks.enter_context(
-                mock.patch.object(os.path, 'exists', return_value=False))
-            mocks.enter_context(
-                mock.patch.object(util, 'write_file', replace_write))
-            mocks.enter_context(
-                mock.patch.object(util, 'load_file', replace_read))
-
-            fbsd_distro.apply_network(BASE_NET_CFG, False)
-
-            self.assertIn('/etc/rc.conf', write_bufs)
-            write_buf = write_bufs['/etc/rc.conf']
-            expected_buf = '''
-ifconfig_vtnet0="192.168.1.5 netmask 255.255.255.0"
-ifconfig_vtnet1="DHCP"
-defaultrouter="192.168.1.254"
-'''
-            self.assertCfgEquals(expected_buf, str(write_buf))
-            self.assertEqual(write_buf.mode, 0o644)
-
-    def test_apply_network_config_fallback(self):
+        tmpd = self.tmp_dir()
+        populate_dir(tmpd, read_bufs)
+        with self.reRooted(tmpd):
+            with mock.patch("cloudinit.distros.freebsd.util.subp",
+                            return_value=('vtnet0', '')):
+                fbsd_distro.apply_network(BASE_NET_CFG, False)
+                results = dir2dict(tmpd)
+
+        self.assertIn(rc_conf, results)
+        self.assertCfgEquals(
+            dedent('''\
+                ifconfig_vtnet0="192.168.1.5 netmask 255.255.255.0"
+                ifconfig_vtnet1="DHCP"
+                defaultrouter="192.168.1.254"
+                '''), results[rc_conf])
+        self.assertEqual(0o644, get_mode(rc_conf, tmpd))
+
+    def test_apply_network_config_fallback_freebsd(self):
         fbsd_distro = self._get_distro('freebsd')
 
         # a weak attempt to verify that we don't have an implementation
@@ -735,68 +279,324 @@ defaultrouter="192.168.1.254"
                         "subnets": [{"type": "dhcp"}]}],
             'version': 1}
 
-        write_bufs = {}
+        rc_conf = '/etc/rc.conf'
         read_bufs = {
-            '/etc/rc.conf': '',
-            '/etc/resolv.conf': '',
+            rc_conf: 'initial-rc-conf-not-validated',
+            '/etc/resolv.conf': 'initial-resolv-conf-not-validated',
         }
 
-        def replace_write(filename, content, mode=0o644, omode="wb"):
-            buf = WriteBuffer()
-            buf.mode = mode
-            buf.omode = omode
-            buf.write(content)
-            write_bufs[filename] = buf
-
-        def replace_read(fname, read_cb=None, quiet=False):
-            if fname not in read_bufs:
-                if fname in write_bufs:
-                    return str(write_bufs[fname])
-                raise IOError("%s not found" % fname)
-            else:
-                if fname in write_bufs:
-                    return str(write_bufs[fname])
-                return read_bufs[fname]
-
-        with ExitStack() as mocks:
-            mocks.enter_context(
-                mock.patch.object(util, 'subp', return_value=('vtnet0', '')))
-            mocks.enter_context(
-                mock.patch.object(os.path, 'exists', return_value=False))
-            mocks.enter_context(
-                mock.patch.object(util, 'write_file', replace_write))
-            mocks.enter_context(
-                mock.patch.object(util, 'load_file', replace_read))
-
-            fbsd_distro.apply_network_config(mynetcfg, bring_up=False)
-
-            self.assertIn('/etc/rc.conf', write_bufs)
-            write_buf = write_bufs['/etc/rc.conf']
-            expected_buf = '''
-ifconfig_vtnet0="DHCP"
-'''
-            self.assertCfgEquals(expected_buf, str(write_buf))
-            self.assertEqual(write_buf.mode, 0o644)
+        tmpd = self.tmp_dir()
+        populate_dir(tmpd, read_bufs)
+        with self.reRooted(tmpd):
+            with mock.patch("cloudinit.distros.freebsd.util.subp",
+                            return_value=('vtnet0', '')):
+                fbsd_distro.apply_network_config(mynetcfg, bring_up=False)
+                results = dir2dict(tmpd)
 
-    def test_simple_write_opensuse(self):
-        """Opensuse network rendering writes appropriate sysconfg files."""
-        tmpdir = self.tmp_dir()
-        self.patchOS(tmpdir)
-        self.patchUtils(tmpdir)
-        distro = self._get_distro('opensuse')
+        self.assertIn(rc_conf, results)
+        self.assertCfgEquals('ifconfig_vtnet0="DHCP"', results[rc_conf])
+        self.assertEqual(0o644, get_mode(rc_conf, tmpd))
 
-        distro.apply_network(BASE_NET_CFG, False)
 
-        lo_path = os.path.join(tmpdir, 'etc/sysconfig/network/ifcfg-lo')
-        eth0_path = os.path.join(tmpdir, 'etc/sysconfig/network/ifcfg-eth0')
-        eth1_path = os.path.join(tmpdir, 'etc/sysconfig/network/ifcfg-eth1')
+class TestNetCfgDistroUbuntuEni(TestNetCfgDistroBase):
+
+    def setUp(self):
+        super(TestNetCfgDistroUbuntuEni, self).setUp()
+        self.distro = self._get_distro('ubuntu', renderers=['eni'])
+
+    def eni_path(self):
+        return '/etc/network/interfaces.d/50-cloud-init.cfg'
+
+    def _apply_and_verify_eni(self, apply_fn, config, expected_cfgs=None,
+                              bringup=False):
+        if not expected_cfgs:
+            raise ValueError('expected_cfg must not be None')
+
+        tmpd = None
+        with mock.patch('cloudinit.net.eni.available') as m_avail:
+            m_avail.return_value = True
+            with self.reRooted(tmpd) as tmpd:
+                apply_fn(config, bringup)
+
+        results = dir2dict(tmpd)
+        for cfgpath, expected in expected_cfgs.items():
+            print("----------")
+            print(expected)
+            print("^^^^ expected | rendered VVVVVVV")
+            print(results[cfgpath])
+            print("----------")
+            self.assertEqual(expected, results[cfgpath])
+            self.assertEqual(0o644, get_mode(cfgpath, tmpd))
+
+    def test_simple_write_ub(self):
+        expected_cfgs = {
+            self.eni_path(): BASE_NET_CFG,
+        }
+
+        # ub_distro.apply_network(BASE_NET_CFG, False)
+        self._apply_and_verify_eni(self.distro.apply_network,
+                                   BASE_NET_CFG,
+                                   expected_cfgs=expected_cfgs.copy())
+
+    def test_apply_network_config_eni_ub(self):
         expected_cfgs = {
-            lo_path: dedent('''
+            self.eni_path(): V1_NET_CFG_OUTPUT,
+        }
+        # ub_distro.apply_network_config(V1_NET_CFG, False)
+        self._apply_and_verify_eni(self.distro.apply_network_config,
+                                   V1_NET_CFG,
+                                   expected_cfgs=expected_cfgs.copy())
+
+
+class TestNetCfgDistroUbuntuNetplan(TestNetCfgDistroBase):
+    def setUp(self):
+        super(TestNetCfgDistroUbuntuNetplan, self).setUp()
+        self.distro = self._get_distro('ubuntu', renderers=['netplan'])
+        self.devlist = ['eth0', 'lo']
+
+    def _apply_and_verify_netplan(self, apply_fn, config, expected_cfgs=None,
+                                  bringup=False):
+        if not expected_cfgs:
+            raise ValueError('expected_cfg must not be None')
+
+        tmpd = None
+        with mock.patch('cloudinit.net.netplan.available',
+                        return_value=True):
+            with mock.patch("cloudinit.net.netplan.get_devicelist",
+                            return_value=self.devlist):
+                with self.reRooted(tmpd) as tmpd:
+                    apply_fn(config, bringup)
+
+        results = dir2dict(tmpd)
+        for cfgpath, expected in expected_cfgs.items():
+            print("----------")
+            print(expected)
+            print("^^^^ expected | rendered VVVVVVV")
+            print(results[cfgpath])
+            print("----------")
+            self.assertEqual(expected, results[cfgpath])
+            self.assertEqual(0o644, get_mode(cfgpath, tmpd))
+
+    def netplan_path(self):
+            return '/etc/netplan/50-cloud-init.yaml'
+
+    def test_apply_network_config_v1_to_netplan_ub(self):
+        expected_cfgs = {
+            self.netplan_path(): V1_TO_V2_NET_CFG_OUTPUT,
+        }
+
+        # ub_distro.apply_network_config(V1_NET_CFG, False)
+        self._apply_and_verify_netplan(self.distro.apply_network_config,
+                                       V1_NET_CFG,
+                                       expected_cfgs=expected_cfgs.copy())
+
+    def test_apply_network_config_v2_passthrough_ub(self):
+        expected_cfgs = {
+            self.netplan_path(): V2_TO_V2_NET_CFG_OUTPUT,
+        }
+        # ub_distro.apply_network_config(V2_NET_CFG, False)
+        self._apply_and_verify_netplan(self.distro.apply_network_config,
+                                       V2_NET_CFG,
+                                       expected_cfgs=expected_cfgs.copy())
+
+
+class TestNetCfgDistroRedhat(TestNetCfgDistroBase):
+
+    def setUp(self):
+        super(TestNetCfgDistroRedhat, self).setUp()
+        self.distro = self._get_distro('rhel', renderers=['sysconfig'])
+
+    def ifcfg_path(self, ifname):
+        return '/etc/sysconfig/network-scripts/ifcfg-%s' % ifname
+
+    def control_path(self):
+        return '/etc/sysconfig/network'
+
+    def _apply_and_verify(self, apply_fn, config, expected_cfgs=None,
+                          bringup=False):
+        if not expected_cfgs:
+            raise ValueError('expected_cfg must not be None')
+
+        tmpd = None
+        with mock.patch('cloudinit.net.sysconfig.available') as m_avail:
+            m_avail.return_value = True
+            with self.reRooted(tmpd) as tmpd:
+                apply_fn(config, bringup)
+
+        results = dir2dict(tmpd)
+        for cfgpath, expected in expected_cfgs.items():
+            self.assertCfgEquals(expected, results[cfgpath])
+            self.assertEqual(0o644, get_mode(cfgpath, tmpd))
+
+    def test_simple_write_rh(self):
+        expected_cfgs = {
+            self.ifcfg_path('lo'): dedent("""\
+                DEVICE="lo"
+                ONBOOT=yes
+                """),
+            self.ifcfg_path('eth0'): dedent("""\
+                DEVICE="eth0"
+                BOOTPROTO="static"
+                NETMASK="255.255.255.0"
+                IPADDR="192.168.1.5"
+                ONBOOT=yes
+                GATEWAY="192.168.1.254"
+                BROADCAST="192.168.1.0"
+                """),
+            self.ifcfg_path('eth1'): dedent("""\
+                DEVICE="eth1"
+                BOOTPROTO="dhcp"
+                ONBOOT=yes
+                """),
+            self.control_path(): dedent("""\
+                NETWORKING=yes
+                """),
+        }
+        # rh_distro.apply_network(BASE_NET_CFG, False)
+        self._apply_and_verify(self.distro.apply_network,
+                               BASE_NET_CFG,
+                               expected_cfgs=expected_cfgs.copy())
+
+    def test_apply_network_config_rh(self):
+        expected_cfgs = {
+            self.ifcfg_path('eth0'): dedent("""\
+                BOOTPROTO=none
+                DEFROUTE=yes
+                DEVICE=eth0
+                GATEWAY=192.168.1.254
+                IPADDR=192.168.1.5
+                NETMASK=255.255.255.0
+                NM_CONTROLLED=no
+                ONBOOT=yes
+                TYPE=Ethernet
+                USERCTL=no
+                """),
+            self.ifcfg_path('eth1'): dedent("""\
+                BOOTPROTO=dhcp
+                DEVICE=eth1
+                NM_CONTROLLED=no
+                ONBOOT=yes
+                TYPE=Ethernet
+                USERCTL=no
+                """),
+            self.control_path(): dedent("""\
+                NETWORKING=yes
+                """),
+        }
+        # rh_distro.apply_network_config(V1_NET_CFG, False)
+        self._apply_and_verify(self.distro.apply_network_config,
+                               V1_NET_CFG,
+                               expected_cfgs=expected_cfgs.copy())
+
+    def test_write_ipv6_rhel(self):
+        expected_cfgs = {
+            self.ifcfg_path('lo'): dedent("""\
+                DEVICE="lo"
+                ONBOOT=yes
+                """),
+            self.ifcfg_path('eth0'): dedent("""\
+                DEVICE="eth0"
+                BOOTPROTO="static"
+                NETMASK="255.255.255.0"
+                IPADDR="192.168.1.5"
+                ONBOOT=yes
+                GATEWAY="192.168.1.254"
+                BROADCAST="192.168.1.0"
+                IPV6INIT=yes
+                IPV6ADDR="2607:f0d0:1002:0011::2"
+                IPV6_DEFAULTGW="2607:f0d0:1002:0011::1"
+                """),
+            self.ifcfg_path('eth1'): dedent("""\
+                DEVICE="eth1"
+                BOOTPROTO="static"
+                NETMASK="255.255.255.0"
+                IPADDR="192.168.1.6"
+                ONBOOT=no
+                GATEWAY="192.168.1.254"
+                BROADCAST="192.168.1.0"
+                IPV6INIT=yes
+                IPV6ADDR="2607:f0d0:1002:0011::3"
+                IPV6_DEFAULTGW="2607:f0d0:1002:0011::1"
+                """),
+            self.control_path(): dedent("""\
+                NETWORKING=yes
+                NETWORKING_IPV6=yes
+                IPV6_AUTOCONF=no
+                """),
+        }
+        # rh_distro.apply_network(BASE_NET_CFG_IPV6, False)
+        self._apply_and_verify(self.distro.apply_network,
+                               BASE_NET_CFG_IPV6,
+                               expected_cfgs=expected_cfgs.copy())
+
+    def test_apply_network_config_ipv6_rh(self):
+        expected_cfgs = {
+            self.ifcfg_path('eth0'): dedent("""\
+                BOOTPROTO=none
+                DEFROUTE=yes
+                DEVICE=eth0
+                IPV6ADDR=2607:f0d0:1002:0011::2/64
+                IPV6INIT=yes
+                IPV6_DEFAULTGW=2607:f0d0:1002:0011::1
+                NM_CONTROLLED=no
+                ONBOOT=yes
+                TYPE=Ethernet
+                USERCTL=no
+                """),
+            self.ifcfg_path('eth1'): dedent("""\
+                BOOTPROTO=dhcp
+                DEVICE=eth1
+                NM_CONTROLLED=no
+                ONBOOT=yes
+                TYPE=Ethernet
+                USERCTL=no
+                """),
+            self.control_path(): dedent("""\
+                NETWORKING=yes
+                NETWORKING_IPV6=yes
+                IPV6_AUTOCONF=no
+                """),
+            }
+        # rh_distro.apply_network_config(V1_NET_CFG_IPV6, False)
+        self._apply_and_verify(self.distro.apply_network_config,
+                               V1_NET_CFG_IPV6,
+                               expected_cfgs=expected_cfgs.copy())
+
+
+class TestNetCfgDistroOpensuse(TestNetCfgDistroBase):
+
+    def setUp(self):
+        super(TestNetCfgDistroOpensuse, self).setUp()
+        self.distro = self._get_distro('opensuse', renderers=['sysconfig'])
+
+    def ifcfg_path(self, ifname):
+        return '/etc/sysconfig/network/ifcfg-%s' % ifname
+
+    def _apply_and_verify(self, apply_fn, config, expected_cfgs=None,
+                          bringup=False):
+        if not expected_cfgs:
+            raise ValueError('expected_cfg must not be None')
+
+        tmpd = None
+        with mock.patch('cloudinit.net.sysconfig.available') as m_avail:
+            m_avail.return_value = True
+            with self.reRooted(tmpd) as tmpd:
+                apply_fn(config, bringup)
+
+        results = dir2dict(tmpd)
+        for cfgpath, expected in expected_cfgs.items():
+            self.assertCfgEquals(expected, results[cfgpath])
+            self.assertEqual(0o644, get_mode(cfgpath, tmpd))
+
+    def test_simple_write_opensuse(self):
+        """Opensuse network rendering writes appropriate sysconfig files."""
+        expected_cfgs = {
+            self.ifcfg_path('lo'): dedent('''
                 STARTMODE="auto"
                 USERCONTROL="no"
                 FIREWALL="no"
                 '''),
-            eth0_path: dedent('''
+            self.ifcfg_path('eth0'): dedent('''
                 BOOTPROTO="static"
                 BROADCAST="192.168.1.0"
                 GATEWAY="192.168.1.254"
@@ -806,18 +606,77 @@ ifconfig_vtnet0="DHCP"
                 USERCONTROL="no"
                 ETHTOOL_OPTIONS=""
                 '''),
-            eth1_path: dedent('''
+            self.ifcfg_path('eth1'): dedent('''
                 BOOTPROTO="dhcp"
                 STARTMODE="auto"
                 USERCONTROL="no"
                 ETHTOOL_OPTIONS=""
                 ''')
         }
-        for cfgpath in (lo_path, eth0_path, eth1_path):
-            self.assertCfgEquals(
-                expected_cfgs[cfgpath],
-                util.load_file(cfgpath))
-            file_stat = os.stat(cfgpath)
-            self.assertEqual(0o644, stat.S_IMODE(file_stat.st_mode))
+
+        # distro.apply_network(BASE_NET_CFG, False)
+        self._apply_and_verify(self.distro.apply_network,
+                               BASE_NET_CFG,
+                               expected_cfgs=expected_cfgs.copy())
+
+    def test_apply_network_config_opensuse(self):
+        """Opensuse uses apply_network_config and renders sysconfig"""
+        expected_cfgs = {
+            self.ifcfg_path('eth0'): dedent("""\
+                BOOTPROTO=none
+                DEFROUTE=yes
+                DEVICE=eth0
+                GATEWAY=192.168.1.254
+                IPADDR=192.168.1.5
+                NETMASK=255.255.255.0
+                NM_CONTROLLED=no
+                ONBOOT=yes
+                TYPE=Ethernet
+                USERCTL=no
+                """),
+            self.ifcfg_path('eth1'): dedent("""\
+                BOOTPROTO=dhcp
+                DEVICE=eth1
+                NM_CONTROLLED=no
+                ONBOOT=yes
+                TYPE=Ethernet
+                USERCTL=no
+                """),
+        }
+        self._apply_and_verify(self.distro.apply_network_config,
+                               V1_NET_CFG,
+                               expected_cfgs=expected_cfgs.copy())
+
+    def test_apply_network_config_ipv6_opensuse(self):
+        """Opensuse uses apply_network_config and renders sysconfig w/ipv6"""
+        expected_cfgs = {
+            self.ifcfg_path('eth0'): dedent("""\
+                BOOTPROTO=none
+                DEFROUTE=yes
+                DEVICE=eth0
+                IPV6ADDR=2607:f0d0:1002:0011::2/64
+                IPV6INIT=yes
+                IPV6_DEFAULTGW=2607:f0d0:1002:0011::1
+                NM_CONTROLLED=no
+                ONBOOT=yes
+                TYPE=Ethernet
+                USERCTL=no
+            """),
+            self.ifcfg_path('eth1'): dedent("""\
+                BOOTPROTO=dhcp
+                DEVICE=eth1
+                NM_CONTROLLED=no
+                ONBOOT=yes
+                TYPE=Ethernet
+                USERCTL=no
+            """),
+        }
+        self._apply_and_verify(self.distro.apply_network_config,
+                               V1_NET_CFG_IPV6,
+                               expected_cfgs=expected_cfgs.copy())
+
+
+def get_mode(path, target=None):
+    return os.stat(util.target_path(target, path)).st_mode & 0o777
 
 # vi: ts=4 expandtab
diff --git a/tests/unittests/test_net.py b/tests/unittests/test_net.py
index 58e5ea14..05d5c72c 100644
--- a/tests/unittests/test_net.py
+++ b/tests/unittests/test_net.py
@@ -1,6 +1,7 @@
 # This file is part of cloud-init. See LICENSE file for license information.
 
 from cloudinit import net
+from cloudinit import distros
 from cloudinit.net import cmdline
 from cloudinit.net import (
     eni, interface_has_own_mac, natural_sort_key, netplan, network_state,
@@ -129,7 +130,40 @@ OS_SAMPLES = [
         'in_macs': {
             'fa:16:3e:ed:9a:59': 'eth0',
         },
-        'out_sysconfig': [
+        'out_sysconfig_opensuse': [
+            ('etc/sysconfig/network/ifcfg-eth0',
+             """
+# Created by cloud-init on instance boot automatically, do not edit.
+#
+BOOTPROTO=none
+DEFROUTE=yes
+DEVICE=eth0
+GATEWAY=172.19.3.254
+HWADDR=fa:16:3e:ed:9a:59
+IPADDR=172.19.1.34
+NETMASK=255.255.252.0
+NM_CONTROLLED=no
+ONBOOT=yes
+TYPE=Ethernet
+USERCTL=no
+""".lstrip()),
+            ('etc/resolv.conf',
+             """
+; Created by cloud-init on instance boot automatically, do not edit.
+;
+nameserver 172.19.0.12
+""".lstrip()),
+            ('etc/NetworkManager/conf.d/99-cloud-init.conf',
+             """
+# Created by cloud-init on instance boot automatically, do not edit.
+#
+[main]
+dns = none
+""".lstrip()),
+            ('etc/udev/rules.d/70-persistent-net.rules',
+             "".join(['SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ',
+                      'ATTR{address}=="fa:16:3e:ed:9a:59", NAME="eth0"\n']))],
+        'out_sysconfig_rhel': [
             ('etc/sysconfig/network-scripts/ifcfg-eth0',
              """
 # Created by cloud-init on instance boot automatically, do not edit.
@@ -162,6 +196,7 @@ dns = none
             ('etc/udev/rules.d/70-persistent-net.rules',
              "".join(['SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ',
                       'ATTR{address}=="fa:16:3e:ed:9a:59", NAME="eth0"\n']))]
+
     },
     {
         'in_data': {
@@ -195,7 +230,42 @@ dns = none
         'in_macs': {
             'fa:16:3e:ed:9a:59': 'eth0',
         },
-        'out_sysconfig': [
+        'out_sysconfig_opensuse': [
+            ('etc/sysconfig/network/ifcfg-eth0',
+             """
+# Created by cloud-init on instance boot automatically, do not edit.
+#
+BOOTPROTO=none
+DEFROUTE=yes
+DEVICE=eth0
+GATEWAY=172.19.3.254
+HWADDR=fa:16:3e:ed:9a:59
+IPADDR=172.19.1.34
+IPADDR1=10.0.0.10
+NETMASK=255.255.252.0
+NETMASK1=255.255.255.0
+NM_CONTROLLED=no
+ONBOOT=yes
+TYPE=Ethernet
+USERCTL=no
+""".lstrip()),
+            ('etc/resolv.conf',
+             """
+; Created by cloud-init on instance boot automatically, do not edit.
+;
+nameserver 172.19.0.12
+""".lstrip()),
+            ('etc/NetworkManager/conf.d/99-cloud-init.conf',
+             """
+# Created by cloud-init on instance boot automatically, do not edit.
+#
+[main]
+dns = none
+""".lstrip()),
+            ('etc/udev/rules.d/70-persistent-net.rules',
+             "".join(['SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ',
+                      'ATTR{address}=="fa:16:3e:ed:9a:59", NAME="eth0"\n']))],
+        'out_sysconfig_rhel': [
             ('etc/sysconfig/network-scripts/ifcfg-eth0',
              """
 # Created by cloud-init on instance boot automatically, do not edit.
@@ -230,6 +300,7 @@ dns = none
             ('etc/udev/rules.d/70-persistent-net.rules',
              "".join(['SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ',
                       'ATTR{address}=="fa:16:3e:ed:9a:59", NAME="eth0"\n']))]
+
     },
     {
         'in_data': {
@@ -283,7 +354,44 @@ dns = none
         'in_macs': {
             'fa:16:3e:ed:9a:59': 'eth0',
         },
-        'out_sysconfig': [
+        'out_sysconfig_opensuse': [
+            ('etc/sysconfig/network/ifcfg-eth0',
+             """
+# Created by cloud-init on instance boot automatically, do not edit.
+#
+BOOTPROTO=none
+DEFROUTE=yes
+DEVICE=eth0
+GATEWAY=172.19.3.254
+HWADDR=fa:16:3e:ed:9a:59
+IPADDR=172.19.1.34
+IPV6ADDR=2001:DB8::10/64
+IPV6ADDR_SECONDARIES="2001:DB9::10/64 2001:DB10::10/64"
+IPV6INIT=yes
+IPV6_DEFAULTGW=2001:DB8::1
+NETMASK=255.255.252.0
+NM_CONTROLLED=no
+ONBOOT=yes
+TYPE=Ethernet
+USERCTL=no
+""".lstrip()),
+            ('etc/resolv.conf',
+             """
+; Created by cloud-init on instance boot automatically, do not edit.
+;
+nameserver 172.19.0.12
+""".lstrip()),
+            ('etc/NetworkManager/conf.d/99-cloud-init.conf',
+             """
+# Created by cloud-init on instance boot automatically, do not edit.
+#
+[main]
+dns = none
+""".lstrip()),
+            ('etc/udev/rules.d/70-persistent-net.rules',
+             "".join(['SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ',
+                      'ATTR{address}=="fa:16:3e:ed:9a:59", NAME="eth0"\n']))],
+        'out_sysconfig_rhel': [
             ('etc/sysconfig/network-scripts/ifcfg-eth0',
              """
 # Created by cloud-init on instance boot automatically, do not edit.
@@ -1154,7 +1262,59 @@ pre-down route del -net 10.0.0.0 netmask 255.0.0.0 gw 11.0.0.1 metric 3 || true
              version: 2
         """),
 
-        'expected_sysconfig': {
+        'expected_sysconfig_opensuse': {
+            'ifcfg-bond0': textwrap.dedent("""\
+        BONDING_MASTER=yes
+        BONDING_OPTS="mode=active-backup xmit_hash_policy=layer3+4 miimon=100"
+        BONDING_SLAVE0=bond0s0
+        BONDING_SLAVE1=bond0s1
+        BOOTPROTO=none
+        DEFROUTE=yes
+        DEVICE=bond0
+        GATEWAY=192.168.0.1
+        MACADDR=aa:bb:cc:dd:e8:ff
+        IPADDR=192.168.0.2
+        IPADDR1=192.168.1.2
+        IPV6ADDR=2001:1::1/92
+        IPV6INIT=yes
+        MTU=9000
+        NETMASK=255.255.255.0
+        NETMASK1=255.255.255.0
+        NM_CONTROLLED=no
+        ONBOOT=yes
+        TYPE=Bond
+        USERCTL=no
+        """),
+            'ifcfg-bond0s0': textwrap.dedent("""\
+        BOOTPROTO=none
+        DEVICE=bond0s0
+        HWADDR=aa:bb:cc:dd:e8:00
+        MASTER=bond0
+        NM_CONTROLLED=no
+        ONBOOT=yes
+        SLAVE=yes
+        TYPE=Ethernet
+        USERCTL=no
+        """),
+            'ifroute-bond0': textwrap.dedent("""\
+        ADDRESS0=10.1.3.0
+        GATEWAY0=192.168.0.3
+        NETMASK0=255.255.255.0
+        """),
+            'ifcfg-bond0s1': textwrap.dedent("""\
+        BOOTPROTO=none
+        DEVICE=bond0s1
+        HWADDR=aa:bb:cc:dd:e8:01
+        MASTER=bond0
+        NM_CONTROLLED=no
+        ONBOOT=yes
+        SLAVE=yes
+        TYPE=Ethernet
+        USERCTL=no
+        """),
+        },
+
+        'expected_sysconfig_rhel': {
             'ifcfg-bond0': textwrap.dedent("""\
         BONDING_MASTER=yes
         BONDING_OPTS="mode=active-backup xmit_hash_policy=layer3+4 miimon=100"
@@ -1527,7 +1687,7 @@ class TestGenerateFallbackConfig(CiTestCase):
         # don't set rulepath so eni writes them
         renderer = eni.Renderer(
             {'eni_path': 'interfaces', 'netrules_path': 'netrules'})
-        renderer.render_network_state(ns, render_dir)
+        renderer.render_network_state(ns, target=render_dir)
 
         self.assertTrue(os.path.exists(os.path.join(render_dir,
                                                     'interfaces')))
@@ -1591,7 +1751,7 @@ iface eth0 inet dhcp
         # don't set rulepath so eni writes them
         renderer = eni.Renderer(
             {'eni_path': 'interfaces', 'netrules_path': 'netrules'})
-        renderer.render_network_state(ns, render_dir)
+        renderer.render_network_state(ns, target=render_dir)
 
         self.assertTrue(os.path.exists(os.path.join(render_dir,
                                                     'interfaces')))
@@ -1682,7 +1842,7 @@ iface eth1 inet dhcp
         self.assertEqual(0, mock_settle.call_count)
 
 
-class TestSysConfigRendering(CiTestCase):
+class TestRhelSysConfigRendering(CiTestCase):
 
     with_logs = True
 
@@ -1690,6 +1850,13 @@ class TestSysConfigRendering(CiTestCase):
     header = ('# Created by cloud-init on instance boot automatically, '
               'do not edit.\n#\n')
 
+    expected_name = 'expected_sysconfig'
+
+    def _get_renderer(self):
+        distro_cls = distros.fetch('rhel')
+        return sysconfig.Renderer(
+            config=distro_cls.renderer_configs.get('sysconfig'))
+
     def _render_and_read(self, network_config=None, state=None, dir=None):
         if dir is None:
             dir = self.tmp_dir()
@@ -1701,8 +1868,8 @@ class TestSysConfigRendering(CiTestCase):
         else:
             raise ValueError("Expected data or state, got neither")
 
-        renderer = sysconfig.Renderer()
-        renderer.render_network_state(ns, dir)
+        renderer = self._get_renderer()
+        renderer.render_network_state(ns, target=dir)
         return dir2dict(dir)
 
     def _compare_files_to_expected(self, expected, found):
@@ -1745,8 +1912,8 @@ class TestSysConfigRendering(CiTestCase):
         render_dir = os.path.join(tmp_dir, "render")
         os.makedirs(render_dir)
 
-        renderer = sysconfig.Renderer()
-        renderer.render_network_state(ns, render_dir)
+        renderer = self._get_renderer()
+        renderer.render_network_state(ns, target=render_dir)
 
         render_file = 'etc/sysconfig/network-scripts/ifcfg-eth1000'
         with open(os.path.join(render_dir, render_file)) as fh:
@@ -1797,9 +1964,9 @@ USERCTL=no
         network_cfg = openstack.convert_net_json(net_json, known_macs=macs)
         ns = network_state.parse_net_config_data(network_cfg,
                                                  skip_broken=False)
-        renderer = sysconfig.Renderer()
+        renderer = self._get_renderer()
         with self.assertRaises(ValueError):
-            renderer.render_network_state(ns, render_dir)
+            renderer.render_network_state(ns, target=render_dir)
         self.assertEqual([], os.listdir(render_dir))
 
     def test_multiple_ipv6_default_gateways(self):
@@ -1835,9 +2002,9 @@ USERCTL=no
         network_cfg = openstack.convert_net_json(net_json, known_macs=macs)
         ns = network_state.parse_net_config_data(network_cfg,
                                                  skip_broken=False)
-        renderer = sysconfig.Renderer()
+        renderer = self._get_renderer()
         with self.assertRaises(ValueError):
-            renderer.render_network_state(ns, render_dir)
+            renderer.render_network_state(ns, target=render_dir)
         self.assertEqual([], os.listdir(render_dir))
 
     def test_openstack_rendering_samples(self):
@@ -1849,12 +2016,13 @@ USERCTL=no
                 ex_input, known_macs=ex_mac_addrs)
             ns = network_state.parse_net_config_data(network_cfg,
                                                      skip_broken=False)
-            renderer = sysconfig.Renderer()
+            renderer = self._get_renderer()
             # render a multiple times to simulate reboots
-            renderer.render_network_state(ns, render_dir)
-            renderer.render_network_state(ns, render_dir)
-            renderer.render_network_state(ns, render_dir)
-            for fn, expected_content in os_sample.get('out_sysconfig', []):
+            renderer.render_network_state(ns, target=render_dir)
+            renderer.render_network_state(ns, target=render_dir)
+            renderer.render_network_state(ns, target=render_dir)
+            for fn, expected_content in os_sample.get('out_sysconfig_rhel',
+                                                      []):
                 with open(os.path.join(render_dir, fn)) as fh:
                     self.assertEqual(expected_content, fh.read())
 
@@ -1862,8 +2030,8 @@ USERCTL=no
         ns = network_state.parse_net_config_data(CONFIG_V1_SIMPLE_SUBNET)
         render_dir = self.tmp_path("render")
         os.makedirs(render_dir)
-        renderer = sysconfig.Renderer()
-        renderer.render_network_state(ns, render_dir)
+        renderer = self._get_renderer()
+        renderer.render_network_state(ns, target=render_dir)
         found = dir2dict(render_dir)
         nspath = '/etc/sysconfig/network-scripts/'
         self.assertNotIn(nspath + 'ifcfg-lo', found.keys())
@@ -1888,8 +2056,8 @@ USERCTL=no
         ns = network_state.parse_net_config_data(CONFIG_V1_EXPLICIT_LOOPBACK)
         render_dir = self.tmp_path("render")
         os.makedirs(render_dir)
-        renderer = sysconfig.Renderer()
-        renderer.render_network_state(ns, render_dir)
+        renderer = self._get_renderer()
+        renderer.render_network_state(ns, target=render_dir)
         found = dir2dict(render_dir)
         nspath = '/etc/sysconfig/network-scripts/'
         self.assertNotIn(nspath + 'ifcfg-lo', found.keys())
@@ -1906,33 +2074,331 @@ USERCTL=no
         self.assertEqual(expected, found[nspath + 'ifcfg-eth0'])
 
     def test_bond_config(self):
+        expected_name = 'expected_sysconfig_rhel'
         entry = NETWORK_CONFIGS['bond']
         found = self._render_and_read(network_config=yaml.load(entry['yaml']))
-        self._compare_files_to_expected(entry['expected_sysconfig'], found)
+        self._compare_files_to_expected(entry[expected_name], found)
+        self._assert_headers(found)
+
+    def test_vlan_config(self):
+        entry = NETWORK_CONFIGS['vlan']
+        found = self._render_and_read(network_config=yaml.load(entry['yaml']))
+        self._compare_files_to_expected(entry[self.expected_name], found)
+        self._assert_headers(found)
+
+    def test_bridge_config(self):
+        entry = NETWORK_CONFIGS['bridge']
+        found = self._render_and_read(network_config=yaml.load(entry['yaml']))
+        self._compare_files_to_expected(entry[self.expected_name], found)
+        self._assert_headers(found)
+
+    def test_manual_config(self):
+        entry = NETWORK_CONFIGS['manual']
+        found = self._render_and_read(network_config=yaml.load(entry['yaml']))
+        self._compare_files_to_expected(entry[self.expected_name], found)
+        self._assert_headers(found)
+
+    def test_all_config(self):
+        entry = NETWORK_CONFIGS['all']
+        found = self._render_and_read(network_config=yaml.load(entry['yaml']))
+        self._compare_files_to_expected(entry[self.expected_name], found)
+        self._assert_headers(found)
+        self.assertNotIn(
+            'WARNING: Network config: ignoring eth0.101 device-level mtu',
+            self.logs.getvalue())
+
+    def test_small_config(self):
+        entry = NETWORK_CONFIGS['small']
+        found = self._render_and_read(network_config=yaml.load(entry['yaml']))
+        self._compare_files_to_expected(entry[self.expected_name], found)
+        self._assert_headers(found)
+
+    def test_v4_and_v6_static_config(self):
+        entry = NETWORK_CONFIGS['v4_and_v6_static']
+        found = self._render_and_read(network_config=yaml.load(entry['yaml']))
+        self._compare_files_to_expected(entry[self.expected_name], found)
+        self._assert_headers(found)
+        expected_msg = (
+            'WARNING: Network config: ignoring iface0 device-level mtu:8999'
+            ' because ipv4 subnet-level mtu:9000 provided.')
+        self.assertIn(expected_msg, self.logs.getvalue())
+
+    def test_dhcpv6_only_config(self):
+        entry = NETWORK_CONFIGS['dhcpv6_only']
+        found = self._render_and_read(network_config=yaml.load(entry['yaml']))
+        self._compare_files_to_expected(entry[self.expected_name], found)
+        self._assert_headers(found)
+
+
+class TestOpenSuseSysConfigRendering(CiTestCase):
+
+    with_logs = True
+
+    scripts_dir = '/etc/sysconfig/network'
+    header = ('# Created by cloud-init on instance boot automatically, '
+              'do not edit.\n#\n')
+
+    expected_name = 'expected_sysconfig'
+
+    def _get_renderer(self):
+        distro_cls = distros.fetch('opensuse')
+        return sysconfig.Renderer(
+            config=distro_cls.renderer_configs.get('sysconfig'))
+
+    def _render_and_read(self, network_config=None, state=None, dir=None):
+        if dir is None:
+            dir = self.tmp_dir()
+
+        if network_config:
+            ns = network_state.parse_net_config_data(network_config)
+        elif state:
+            ns = state
+        else:
+            raise ValueError("Expected data or state, got neither")
+
+        renderer = self._get_renderer()
+        renderer.render_network_state(ns, target=dir)
+        return dir2dict(dir)
+
+    def _compare_files_to_expected(self, expected, found):
+        orig_maxdiff = self.maxDiff
+        expected_d = dict(
+            (os.path.join(self.scripts_dir, k), util.load_shell_content(v))
+            for k, v in expected.items())
+
+        # only compare the files in scripts_dir
+        scripts_found = dict(
+            (k, util.load_shell_content(v)) for k, v in found.items()
+            if k.startswith(self.scripts_dir))
+        try:
+            self.maxDiff = None
+            self.assertEqual(expected_d, scripts_found)
+        finally:
+            self.maxDiff = orig_maxdiff
+
+    def _assert_headers(self, found):
+        missing = [f for f in found
+                   if (f.startswith(self.scripts_dir) and
+                       not found[f].startswith(self.header))]
+        if missing:
+            raise AssertionError("Missing headers in: %s" % missing)
+
+    @mock.patch("cloudinit.net.sys_dev_path")
+    @mock.patch("cloudinit.net.read_sys_net")
+    @mock.patch("cloudinit.net.get_devicelist")
+    def test_default_generation(self, mock_get_devicelist,
+                                mock_read_sys_net,
+                                mock_sys_dev_path):
+        tmp_dir = self.tmp_dir()
+        _setup_test(tmp_dir, mock_get_devicelist,
+                    mock_read_sys_net, mock_sys_dev_path)
+
+        network_cfg = net.generate_fallback_config()
+        ns = network_state.parse_net_config_data(network_cfg,
+                                                 skip_broken=False)
+
+        render_dir = os.path.join(tmp_dir, "render")
+        os.makedirs(render_dir)
+
+        renderer = self._get_renderer()
+        renderer.render_network_state(ns, target=render_dir)
+
+        render_file = 'etc/sysconfig/network/ifcfg-eth1000'
+        with open(os.path.join(render_dir, render_file)) as fh:
+            content = fh.read()
+            expected_content = """
+# Created by cloud-init on instance boot automatically, do not edit.
+#
+BOOTPROTO=dhcp
+DEVICE=eth1000
+HWADDR=07-1C-C6-75-A4-BE
+NM_CONTROLLED=no
+ONBOOT=yes
+TYPE=Ethernet
+USERCTL=no
+""".lstrip()
+            self.assertEqual(expected_content, content)
+
+    def test_multiple_ipv4_default_gateways(self):
+        """ValueError is raised when duplicate ipv4 gateways exist."""
+        net_json = {
+            "services": [{"type": "dns", "address": "172.19.0.12"}],
+            "networks": [{
+                "network_id": "dacd568d-5be6-4786-91fe-750c374b78b4",
+                "type": "ipv4", "netmask": "255.255.252.0",
+                "link": "tap1a81968a-79",
+                "routes": [{
+                    "netmask": "0.0.0.0",
+                    "network": "0.0.0.0",
+                    "gateway": "172.19.3.254",
+                }, {
+                    "netmask": "0.0.0.0",  # A second default gateway
+                    "network": "0.0.0.0",
+                    "gateway": "172.20.3.254",
+                }],
+                "ip_address": "172.19.1.34", "id": "network0"
+            }],
+            "links": [
+                {
+                    "ethernet_mac_address": "fa:16:3e:ed:9a:59",
+                    "mtu": None, "type": "bridge", "id":
+                    "tap1a81968a-79",
+                    "vif_id": "1a81968a-797a-400f-8a80-567f997eb93f"
+                },
+            ],
+        }
+        macs = {'fa:16:3e:ed:9a:59': 'eth0'}
+        render_dir = self.tmp_dir()
+        network_cfg = openstack.convert_net_json(net_json, known_macs=macs)
+        ns = network_state.parse_net_config_data(network_cfg,
+                                                 skip_broken=False)
+        renderer = self._get_renderer()
+        with self.assertRaises(ValueError):
+            renderer.render_network_state(ns, target=render_dir)
+        self.assertEqual([], os.listdir(render_dir))
+
+    def test_multiple_ipv6_default_gateways(self):
+        """ValueError is raised when duplicate ipv6 gateways exist."""
+        net_json = {
+            "services": [{"type": "dns", "address": "172.19.0.12"}],
+            "networks": [{
+                "network_id": "public-ipv6",
+                "type": "ipv6", "netmask": "",
+                "link": "tap1a81968a-79",
+                "routes": [{
+                    "gateway": "2001:DB8::1",
+                    "netmask": "::",
+                    "network": "::"
+                }, {
+                    "gateway": "2001:DB9::1",
+                    "netmask": "::",
+                    "network": "::"
+                }],
+                "ip_address": "2001:DB8::10", "id": "network1"
+            }],
+            "links": [
+                {
+                    "ethernet_mac_address": "fa:16:3e:ed:9a:59",
+                    "mtu": None, "type": "bridge", "id":
+                    "tap1a81968a-79",
+                    "vif_id": "1a81968a-797a-400f-8a80-567f997eb93f"
+                },
+            ],
+        }
+        macs = {'fa:16:3e:ed:9a:59': 'eth0'}
+        render_dir = self.tmp_dir()
+        network_cfg = openstack.convert_net_json(net_json, known_macs=macs)
+        ns = network_state.parse_net_config_data(network_cfg,
+                                                 skip_broken=False)
+        renderer = self._get_renderer()
+        with self.assertRaises(ValueError):
+            renderer.render_network_state(ns, target=render_dir)
+        self.assertEqual([], os.listdir(render_dir))
+
+    def test_openstack_rendering_samples(self):
+        for os_sample in OS_SAMPLES:
+            render_dir = self.tmp_dir()
+            ex_input = os_sample['in_data']
+            ex_mac_addrs = os_sample['in_macs']
+            network_cfg = openstack.convert_net_json(
+                ex_input, known_macs=ex_mac_addrs)
+            ns = network_state.parse_net_config_data(network_cfg,
+                                                     skip_broken=False)
+            renderer = self._get_renderer()
+            # render a multiple times to simulate reboots
+            renderer.render_network_state(ns, target=render_dir)
+            renderer.render_network_state(ns, target=render_dir)
+            renderer.render_network_state(ns, target=render_dir)
+            for fn, expected_content in os_sample.get('out_sysconfig_opensuse',
+                                                      []):
+                with open(os.path.join(render_dir, fn)) as fh:
+                    self.assertEqual(expected_content, fh.read())
+
+    def test_network_config_v1_samples(self):
+        ns = network_state.parse_net_config_data(CONFIG_V1_SIMPLE_SUBNET)
+        render_dir = self.tmp_path("render")
+        os.makedirs(render_dir)
+        renderer = self._get_renderer()
+        renderer.render_network_state(ns, target=render_dir)
+        found = dir2dict(render_dir)
+        nspath = '/etc/sysconfig/network/'
+        self.assertNotIn(nspath + 'ifcfg-lo', found.keys())
+        expected = """\
+# Created by cloud-init on instance boot automatically, do not edit.
+#
+BOOTPROTO=none
+DEFROUTE=yes
+DEVICE=interface0
+GATEWAY=10.0.2.2
+HWADDR=52:54:00:12:34:00
+IPADDR=10.0.2.15
+NETMASK=255.255.255.0
+NM_CONTROLLED=no
+ONBOOT=yes
+TYPE=Ethernet
+USERCTL=no
+"""
+        self.assertEqual(expected, found[nspath + 'ifcfg-interface0'])
+
+    def test_config_with_explicit_loopback(self):
+        ns = network_state.parse_net_config_data(CONFIG_V1_EXPLICIT_LOOPBACK)
+        render_dir = self.tmp_path("render")
+        os.makedirs(render_dir)
+        renderer = self._get_renderer()
+        renderer.render_network_state(ns, target=render_dir)
+        found = dir2dict(render_dir)
+        nspath = '/etc/sysconfig/network/'
+        self.assertNotIn(nspath + 'ifcfg-lo', found.keys())
+        expected = """\
+# Created by cloud-init on instance boot automatically, do not edit.
+#
+BOOTPROTO=dhcp
+DEVICE=eth0
+NM_CONTROLLED=no
+ONBOOT=yes
+TYPE=Ethernet
+USERCTL=no
+"""
+        self.assertEqual(expected, found[nspath + 'ifcfg-eth0'])
+
+    def test_bond_config(self):
+        expected_name = 'expected_sysconfig_opensuse'
+        entry = NETWORK_CONFIGS['bond']
+        found = self._render_and_read(network_config=yaml.load(entry['yaml']))
+        for fname, contents in entry[expected_name].items():
+            print(fname)
+            print(contents)
+            print()
+        print('-- expected ^ | v rendered --')
+        for fname, contents in found.items():
+            print(fname)
+            print(contents)
+            print()
+        self._compare_files_to_expected(entry[expected_name], found)
         self._assert_headers(found)
 
     def test_vlan_config(self):
         entry = NETWORK_CONFIGS['vlan']
         found = self._render_and_read(network_config=yaml.load(entry['yaml']))
-        self._compare_files_to_expected(entry['expected_sysconfig'], found)
+        self._compare_files_to_expected(entry[self.expected_name], found)
         self._assert_headers(found)
 
     def test_bridge_config(self):
         entry = NETWORK_CONFIGS['bridge']
         found = self._render_and_read(network_config=yaml.load(entry['yaml']))
-        self._compare_files_to_expected(entry['expected_sysconfig'], found)
+        self._compare_files_to_expected(entry[self.expected_name], found)
         self._assert_headers(found)
 
     def test_manual_config(self):
         entry = NETWORK_CONFIGS['manual']
         found = self._render_and_read(network_config=yaml.load(entry['yaml']))
-        self._compare_files_to_expected(entry['expected_sysconfig'], found)
+        self._compare_files_to_expected(entry[self.expected_name], found)
         self._assert_headers(found)
 
     def test_all_config(self):
         entry = NETWORK_CONFIGS['all']
         found = self._render_and_read(network_config=yaml.load(entry['yaml']))
-        self._compare_files_to_expected(entry['expected_sysconfig'], found)
+        self._compare_files_to_expected(entry[self.expected_name], found)
         self._assert_headers(found)
         self.assertNotIn(
             'WARNING: Network config: ignoring eth0.101 device-level mtu',
@@ -1941,13 +2407,13 @@ USERCTL=no
     def test_small_config(self):
         entry = NETWORK_CONFIGS['small']
         found = self._render_and_read(network_config=yaml.load(entry['yaml']))
-        self._compare_files_to_expected(entry['expected_sysconfig'], found)
+        self._compare_files_to_expected(entry[self.expected_name], found)
         self._assert_headers(found)
 
     def test_v4_and_v6_static_config(self):
         entry = NETWORK_CONFIGS['v4_and_v6_static']
         found = self._render_and_read(network_config=yaml.load(entry['yaml']))
-        self._compare_files_to_expected(entry['expected_sysconfig'], found)
+        self._compare_files_to_expected(entry[self.expected_name], found)
         self._assert_headers(found)
         expected_msg = (
             'WARNING: Network config: ignoring iface0 device-level mtu:8999'
@@ -1957,7 +2423,7 @@ USERCTL=no
     def test_dhcpv6_only_config(self):
         entry = NETWORK_CONFIGS['dhcpv6_only']
         found = self._render_and_read(network_config=yaml.load(entry['yaml']))
-        self._compare_files_to_expected(entry['expected_sysconfig'], found)
+        self._compare_files_to_expected(entry[self.expected_name], found)
         self._assert_headers(found)
 
 
@@ -1982,7 +2448,7 @@ class TestEniNetRendering(CiTestCase):
 
         renderer = eni.Renderer(
             {'eni_path': 'interfaces', 'netrules_path': None})
-        renderer.render_network_state(ns, render_dir)
+        renderer.render_network_state(ns, target=render_dir)
 
         self.assertTrue(os.path.exists(os.path.join(render_dir,
                                                     'interfaces')))
@@ -2002,7 +2468,7 @@ iface eth1000 inet dhcp
         tmp_dir = self.tmp_dir()
         ns = network_state.parse_net_config_data(CONFIG_V1_EXPLICIT_LOOPBACK)
         renderer = eni.Renderer()
-        renderer.render_network_state(ns, tmp_dir)
+        renderer.render_network_state(ns, target=tmp_dir)
         expected = """\
 auto lo
 iface lo inet loopback
@@ -2038,7 +2504,7 @@ class TestNetplanNetRendering(CiTestCase):
         render_target = 'netplan.yaml'
         renderer = netplan.Renderer(
             {'netplan_path': render_target, 'postcmds': False})
-        renderer.render_network_state(ns, render_dir)
+        renderer.render_network_state(ns, target=render_dir)
 
         self.assertTrue(os.path.exists(os.path.join(render_dir,
                                                     render_target)))
@@ -2143,7 +2609,7 @@ class TestNetplanPostcommands(CiTestCase):
         render_target = 'netplan.yaml'
         renderer = netplan.Renderer(
             {'netplan_path': render_target, 'postcmds': True})
-        renderer.render_network_state(ns, render_dir)
+        renderer.render_network_state(ns, target=render_dir)
 
         mock_netplan_generate.assert_called_with(run=True)
         mock_net_setup_link.assert_called_with(run=True)
@@ -2168,7 +2634,7 @@ class TestNetplanPostcommands(CiTestCase):
                        '/sys/class/net/lo'], capture=True),
         ]
         with mock.patch.object(os.path, 'islink', return_value=True):
-            renderer.render_network_state(ns, render_dir)
+            renderer.render_network_state(ns, target=render_dir)
             mock_subp.assert_has_calls(expected)
 
 
@@ -2363,7 +2829,7 @@ class TestNetplanRoundTrip(CiTestCase):
         renderer = netplan.Renderer(
             config={'netplan_path': netplan_path})
 
-        renderer.render_network_state(ns, target)
+        renderer.render_network_state(ns, target=target)
         return dir2dict(target)
 
     def testsimple_render_bond_netplan(self):
@@ -2453,7 +2919,7 @@ class TestEniRoundTrip(CiTestCase):
         renderer = eni.Renderer(
             config={'eni_path': eni_path, 'netrules_path': netrules_path})
 
-        renderer.render_network_state(ns, dir)
+        renderer.render_network_state(ns, target=dir)
         return dir2dict(dir)
 
     def testsimple_convert_and_render(self):