diff --git a/cloudinit/net/__init__.py b/cloudinit/net/__init__.py
index bf21633b1fb..c0888f52702 100644
--- a/cloudinit/net/__init__.py
+++ b/cloudinit/net/__init__.py
@@ -571,7 +571,12 @@ def generate_fallback_config(config_driver=None):
         match = {
             "macaddress": read_sys_net_safe(target_name, "address").lower()
         }
-    cfg = {"dhcp4": True, "set-name": target_name, "match": match}
+    cfg = {
+        "dhcp4": True,
+        "dhcp6": True,
+        "set-name": target_name,
+        "match": match,
+    }
     if config_driver:
         driver = device_driver(target_name)
         if driver:
diff --git a/tests/unittests/net/test_init.py b/tests/unittests/net/test_init.py
index 561d5151d3f..60a44186efa 100644
--- a/tests/unittests/net/test_init.py
+++ b/tests/unittests/net/test_init.py
@@ -261,6 +261,7 @@ def test_generate_fallback_finds_connected_eth_with_mac(self):
                 "eth1": {
                     "match": {"macaddress": mac},
                     "dhcp4": True,
+                    "dhcp6": True,
                     "set-name": "eth1",
                 }
             },
@@ -278,6 +279,7 @@ def test_generate_fallback_finds_dormant_eth_with_mac(self):
                 "eth0": {
                     "match": {"macaddress": mac},
                     "dhcp4": True,
+                    "dhcp6": True,
                     "set-name": "eth0",
                 }
             },
@@ -293,6 +295,7 @@ def test_generate_fallback_finds_eth_by_operstate(self):
             "ethernets": {
                 "eth0": {
                     "dhcp4": True,
+                    "dhcp6": True,
                     "match": {"macaddress": mac},
                     "set-name": "eth0",
                 }
@@ -359,6 +362,7 @@ def is_netfail_master(iface, _driver=None):
             "ethernets": {
                 "ens3": {
                     "dhcp4": True,
+                    "dhcp6": True,
                     "match": {"name": "ens3"},
                     "set-name": "ens3",
                 }
diff --git a/tests/unittests/test_net.py b/tests/unittests/test_net.py
index 3e8f721f098..fbba583c808 100644
--- a/tests/unittests/test_net.py
+++ b/tests/unittests/test_net.py
@@ -4287,6 +4287,7 @@ def test_device_driver_v2(
             "ethernets": {
                 "eth0": {
                     "dhcp4": True,
+                    "dhcp6": True,
                     "set-name": "eth0",
                     "match": {
                         "macaddress": "00:11:22:33:44:55",
@@ -4371,6 +4372,9 @@ def test_device_driver(
 
 auto eth0
 iface eth0 inet dhcp
+
+# control-alias eth0
+iface eth0 inet6 dhcp
 """
         self.assertEqual(expected.lstrip(), contents.lstrip())
 
@@ -4460,6 +4464,9 @@ def test_hv_netvsc_vf_filter(
 
 auto eth1
 iface eth1 inet dhcp
+
+# control-alias eth1
+iface eth1 inet6 dhcp
 """
         self.assertEqual(expected.lstrip(), contents.lstrip())
 
@@ -4683,7 +4690,9 @@ def test_default_generation(
 #
 BOOTPROTO=dhcp
 DEVICE=eth1000
+DHCPV6C=yes
 HWADDR=07-1c-c6-75-a4-be
+IPV6INIT=yes
 NM_CONTROLLED=no
 ONBOOT=yes
 TYPE=Ethernet
@@ -5594,7 +5603,8 @@ def test_default_generation(
             expected_content = """
 # Created by cloud-init automatically, do not edit.
 #
-BOOTPROTO=dhcp4
+BOOTPROTO=dhcp
+DHCLIENT6_MODE=managed
 LLADDR=07-1c-c6-75-a4-be
 STARTMODE=auto
 """.lstrip()
@@ -5976,6 +5986,10 @@ def test_default_generation(
                 method=auto
                 may-fail=false
 
+                [ipv6]
+                method=auto
+                may-fail=false
+
                 """
                 ),
             },
@@ -6240,6 +6254,9 @@ def test_default_generation(
 
 auto eth1000
 iface eth1000 inet dhcp
+
+# control-alias eth1000
+iface eth1000 inet6 dhcp
 """
         self.assertEqual(expected.lstrip(), contents.lstrip())
 
@@ -6299,6 +6316,7 @@ class TestNetplanNetRendering:
                   ethernets:
                     eth1000:
                       dhcp4: true
+                      dhcp6: true
                       match:
                         macaddress: 07-1c-c6-75-a4-be
                       set-name: eth1000
@@ -7798,7 +7816,7 @@ def test_networkd_default_generation(
             Name=eth1000
             MACAddress=07-1c-c6-75-a4-be
             [Network]
-            DHCP=ipv4"""
+            DHCP=yes"""
         ).rstrip(" ")
 
         expected = self.create_conf_dict(expected.splitlines())