net: allow for NetworkManager configuration for NetworkManager net renderer

cloudinit/net/network_manager.py

@@ -17,6 +17,7 @@
 from cloudinit import subp, util
 from cloudinit.net import is_ipv6_address, renderer, subnet_is_ipv6
 from cloudinit.net.network_state import NetworkState
+from cloudinit.net.sysconfig import NM_CONF_PATH, disable_nm_dns_handling
 
 NM_RUN_DIR = "/etc/NetworkManager"
 NM_LIB_DIR = "/usr/lib/NetworkManager"
@@ -350,7 +351,7 @@ class Renderer(renderer.Renderer):
 
     def __init__(self, config=None):
         self.connections = {}
-        self.config = config
+        self.config = {} if not config else config
 
     def get_conn(self, con_id):
         return self.connections[con_id]
@@ -389,17 +390,31 @@ def render_network_state(
         # Select EUI64 to be used by default by NM for creating the address
         # for use with RFC4862 IPv6 Stateless Address Autoconfiguration.
         util.write_file(
-            cloud_init_nm_conf_filename(target), NM_IPV6_ADDR_GEN_CONF, 0o600
+            cloud_init_nm_ip6_addr_gen_conf_filename(target),
+            NM_IPV6_ADDR_GEN_CONF,
+            0o600,
         )
 
+        nm_conf_filename = self.config.get(
+            "networkmanager_conf_path", NM_CONF_PATH
+        )
+
+        nm_conf_content = disable_nm_dns_handling(network_state, templates)
+        if nm_conf_content:
+            util.write_file(
+                f"{target}/{nm_conf_filename}",
+                nm_conf_content,
+                0o600,
+            )
+
 
 def conn_filename(con_id, target=None):
     target_con_dir = subp.target_path(target, NM_RUN_DIR)
     con_file = f"cloud-init-{con_id}.nmconnection"
     return f"{target_con_dir}/system-connections/{con_file}"
 
 
-def cloud_init_nm_conf_filename(target=None):
+def cloud_init_nm_ip6_addr_gen_conf_filename(target=None):
     target_con_dir = subp.target_path(target, NM_RUN_DIR)
     conf_file = "30-cloud-init-ip6-addr-gen-mode.conf"
     return f"{target_con_dir}/conf.d/{conf_file}"

cloudinit/net/sysconfig.py

@@ -36,6 +36,7 @@
     "TencentOS",
     "virtuozzo",
 ]
+NM_CONF_PATH = "etc/NetworkManager/conf.d/99-cloud-init.conf"
 
 
 def _make_header(sep="#"):
@@ -67,6 +68,21 @@ def _quote_value(value):
         return value
 
 
+def disable_nm_dns_handling(network_state, templates=None):
+    content = networkmanager_conf.NetworkManagerConf("")
+
+    # If DNS server information is provided, configure
+    # NetworkManager to not manage dns, so that /etc/resolv.conf
+    # does not get clobbered.
+    if network_state.dns_nameservers:
+        content.set_section_keypair("main", "dns", "none")
+
+    if len(content) == 0:
+        return None
+    out = "".join([_make_header(), "\n", "\n".join(content.write()), "\n"])
+    return out
+
+
 class ConfigMap:
     """Sysconfig like dictionary object."""
 
@@ -374,9 +390,8 @@ def __init__(self, config=None):
             "netrules_path", "etc/udev/rules.d/70-persistent-net.rules"
         )
         self.dns_path = config.get("dns_path", "etc/resolv.conf")
-        nm_conf_path = "etc/NetworkManager/conf.d/99-cloud-init.conf"
         self.networkmanager_conf_path = config.get(
-            "networkmanager_conf_path", nm_conf_path
+            "networkmanager_conf_path", NM_CONF_PATH
         )
         self.templates = {
             "control": config.get("control"),
@@ -846,21 +861,6 @@ def _render_dns(network_state, existing_dns_path=None):
             content_str = header + "\n" + content_str
         return content_str
 
-    @staticmethod
-    def _render_networkmanager_conf(network_state, templates=None):
-        content = networkmanager_conf.NetworkManagerConf("")
-
-        # If DNS server information is provided, configure
-        # NetworkManager to not manage dns, so that /etc/resolv.conf
-        # does not get clobbered.
-        if network_state.dns_nameservers:
-            content.set_section_keypair("main", "dns", "none")
-
-        if len(content) == 0:
-            return None
-        out = "".join([_make_header(), "\n", "\n".join(content.write()), "\n"])
-        return out
-
     @classmethod
     def _render_bridge_interfaces(cls, network_state, iface_contents, flavor):
         bridge_key_map = {
@@ -1006,9 +1006,7 @@ def render_network_state(
             nm_conf_path = subp.target_path(
                 target, self.networkmanager_conf_path
             )
-            nm_conf_content = self._render_networkmanager_conf(
-                network_state, templates
-            )
+            nm_conf_content = disable_nm_dns_handling(network_state, templates)
             if nm_conf_content:
                 util.write_file(nm_conf_path, nm_conf_content, file_mode)
         if self.netrules_path:

tests/unittests/test_net.py

@@ -5887,6 +5887,16 @@ class TestNetworkManagerRendering(CiTestCase):
                 """
         ),
     }
+    expected_nm_conf_d = {
+        "99-cloud-init.conf": textwrap.dedent(
+            """\
+                # Created by cloud-init automatically, do not edit.
+                #
+                [main]
+                dns = none
+                """
+        ),
+    }
 
     def _get_renderer(self):
         return network_manager.Renderer()
@@ -6109,7 +6119,9 @@ 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], self.expected_conf_d, found
+            entry[self.expected_name],
+            {**self.expected_conf_d, **self.expected_nm_conf_d},
+            found,
         )
         self.assertNotIn(
             "WARNING: Network config: ignoring eth0.101 device-level mtu",
@@ -6120,14 +6132,18 @@ def test_small_config_v1(self):
         entry = NETWORK_CONFIGS["small_v1"]
         found = self._render_and_read(network_config=yaml.load(entry["yaml"]))
         self._compare_files_to_expected(
-            entry[self.expected_name], self.expected_conf_d, found
+            entry[self.expected_name],
+            {**self.expected_conf_d, **self.expected_nm_conf_d},
+            found,
         )
 
     def test_small_config_v2(self):
         entry = NETWORK_CONFIGS["small_v2"]
         found = self._render_and_read(network_config=yaml.load(entry["yaml"]))
         self._compare_files_to_expected(
-            entry[self.expected_name], self.expected_conf_d, found
+            entry[self.expected_name],
+            {**self.expected_conf_d, **self.expected_nm_conf_d},
+            found,
         )
 
     def test_v4_and_v6_static_config(self):