Merge ~chad.smith/cloud-init:feature/azure-dhcp-coldplug into cloud-init:master

[Chad Smith]

WIP for discussion

d8c9e65... by Chad Smith on 2018-06-14

revert local test changes

63e40e1... by Chad Smith on 2018-06-25

wip

857c1bc... by Chad Smith on 2018-06-26

revert remove azure unit tests

Unmerged commits

857c1bc... by Chad Smith on 2018-06-26

revert remove azure unit tests

63e40e1... by Chad Smith on 2018-06-25

wip

d8c9e65... by Chad Smith on 2018-06-14

revert local test changes

1bb8aeb... by Chad Smith on 2018-06-14

add maintenance event string lookup for logging

5c146bb... by Chad Smith on 2018-06-14

hook into datasource.maintain_metadata

9967383... by Chad Smith on 2018-06-14

WIP: Azure react to network config changes on each reboot

diff --git a/cloudinit/hotplug.py b/cloudinit/hotplug.py
new file mode 100644
index 0000000..7e4daeb
--- /dev/null
+++ b/cloudinit/hotplug.py
@@ -0,0 +1,17 @@
+# This file is part of cloud-init. See LICENSE file for license information.
+"""Classes and functions related to hotplug and eventing."""
+
+# Maintenance events describing the source generating a maintenance request.
+class MaintenanceEvent(object):
+    NONE = 0x0           # React to no maintenance events
+    BOOT = 0x1           # Any system boot or reboot event
+    DEVICE_ADD = 0x2     # Any new device added
+    DEVICE_REMOVE = 0x4  # Any device removed
+    DEVICE_CHANGE = 0x8  # Any device metadata change
+    ANY = 0xF            # Match any defined MaintenanceEvents
+
+
+MAINTENANCE_EVENT_STR = dict(
+    (attr, getattr(MaintenanceEvent, attr))
+    for attr in MaintenanceEvent.__dict__.keys() if attr.isupper())
+
diff --git a/cloudinit/sources/DataSourceAltCloud.py b/cloudinit/sources/DataSourceAltCloud.py
index 5270fda..dbd79ba 100644
--- a/cloudinit/sources/DataSourceAltCloud.py
+++ b/cloudinit/sources/DataSourceAltCloud.py
@@ -123,7 +123,7 @@ class DataSourceAltCloud(sources.DataSource):
 
         return 'UNKNOWN'
 
-    def _get_data(self):
+    def _get_data(self, clear_cache=False):
         '''
         Description:
             User Data is passed to the launching instance which
diff --git a/cloudinit/sources/DataSourceAzure.py b/cloudinit/sources/DataSourceAzure.py
old mode 100755
new mode 100644
index d2fad9b..996285e
--- a/cloudinit/sources/DataSourceAzure.py
+++ b/cloudinit/sources/DataSourceAzure.py
@@ -18,7 +18,11 @@ import xml.etree.ElementTree as ET
 
 from cloudinit import log as logging
 from cloudinit import net
+<<<<<<< cloudinit/sources/DataSourceAzure.py
 from cloudinit.event import EventType
+=======
+from cloudinit.hotplug import MaintenanceEvent
+>>>>>>> cloudinit/sources/DataSourceAzure.py
 from cloudinit.net.dhcp import EphemeralDHCPv4
 from cloudinit import sources
 from cloudinit.sources.helpers import netlink
@@ -56,6 +60,7 @@ DEFAULT_FS = 'ext4'
 AZURE_CHASSIS_ASSET_TAG = '7783-7084-3265-9085-8269-3286-77'
 REPROVISION_MARKER_FILE = "/var/lib/cloud/data/poll_imds"
 REPORTED_READY_MARKER_FILE = "/var/lib/cloud/data/reported_ready"
+<<<<<<< cloudinit/sources/DataSourceAzure.py
 AGENT_SEED_DIR = '/var/lib/waagent'
 
 # In the event where the IMDS primary server is not
@@ -73,6 +78,9 @@ UBUNTU_EXTENDED_NETWORK_SCRIPTS = [
     '/etc/udev/rules.d/10-net-device-added.rules',
     '/run/network/interfaces.ephemeral.d',
 ]
+=======
+IMDS_URL = "http://169.254.169.254/metadata/"
+>>>>>>> cloudinit/sources/DataSourceAzure.py
 
 
 def find_storvscid_from_sysctl_pnpinfo(sysctl_out, deviceid):
@@ -281,6 +289,12 @@ class DataSourceAzure(sources.DataSource):
     dsname = 'Azure'
     _negotiated = False
     _metadata_imds = sources.UNSET
+<<<<<<< cloudinit/sources/DataSourceAzure.py
+=======
+
+    # Only regenerate network config on system boot for Azure
+    network_maintenance_mask = MaintenanceEvent.BOOT
+>>>>>>> cloudinit/sources/DataSourceAzure.py
 
     def __init__(self, sys_cfg, distro, paths):
         sources.DataSource.__init__(self, sys_cfg, distro, paths)
@@ -373,6 +387,7 @@ class DataSourceAzure(sources.DataSource):
         metadata['public-keys'] = key_value or pubkeys_from_crt_files(fp_files)
         return metadata
 
+<<<<<<< cloudinit/sources/DataSourceAzure.py
     def _get_subplatform(self):
         """Return the subplatform metadata source details."""
         if self.seed.startswith('/dev'):
@@ -390,6 +405,17 @@ class DataSourceAzure(sources.DataSource):
             unavailable, broken or disabled.
         """
         crawled_data = {}
+=======
+
+    @property
+    def region(self):
+        imds_compute_metadata = self.metadata.get('imds', {}).get('compute', {})
+        if imds_compute_metadata:
+            return imds_compute_metadata.get('location')
+        return None
+
+    def _get_data(self, clear_cache=False):
+>>>>>>> cloudinit/sources/DataSourceAzure.py
         # azure removes/ejects the cdrom containing the ovf-env.xml
         # file on reboot.  So, in order to successfully reboot we
         # need to look in the datadir and consider that valid
@@ -434,6 +460,7 @@ class DataSourceAzure(sources.DataSource):
                     LOG.error(msg)
                     raise sources.InvalidMetaDataException(msg)
                 ret = self._reprovision()
+<<<<<<< cloudinit/sources/DataSourceAzure.py
             imds_md = get_metadata_from_imds(
                 self.fallback_interface, retries=10)
             (md, userdata_raw, cfg, files) = ret
@@ -444,6 +471,16 @@ class DataSourceAzure(sources.DataSource):
                 'metadata': util.mergemanydict(
                     [md, {'imds': imds_md}]),
                 'userdata_raw': userdata_raw})
+=======
+            if self._metadata_imds == sources.UNSET:
+                self._metadata_imds = get_metadata_from_imds(
+                    self.fallback_interface, retries=3)
+
+            (md, self.userdata_raw, cfg, files) = ret
+            self.seed = cdev
+            self.metadata = util.mergemanydict([md, {'imds': self._metadata_imds}, DEFAULT_METADATA])
+            self.cfg = util.mergemanydict([cfg, BUILTIN_CLOUD_CONFIG])
+>>>>>>> cloudinit/sources/DataSourceAzure.py
             found = cdev
 
             LOG.debug("found datasource in %s", cdev)
@@ -562,6 +599,7 @@ class DataSourceAzure(sources.DataSource):
         LOG.debug("Wait for vnetswitch to happen")
         while True:
             try:
+<<<<<<< cloudinit/sources/DataSourceAzure.py
                 # Save our EphemeralDHCPv4 context so we avoid repeated dhcp
                 self._ephemeral_dhcp_ctx = EphemeralDHCPv4()
                 lease = self._ephemeral_dhcp_ctx.obtain_lease()
@@ -590,6 +628,19 @@ class DataSourceAzure(sources.DataSource):
                     return readurl(url, timeout=IMDS_TIMEOUT_IN_SECONDS,
                                    headers=headers, exception_cb=exc_cb,
                                    infinite=True, log_req_resp=False).contents
+=======
+                with EphemeralDHCPv4() as lease:
+                    if report_ready:
+                        path = REPORTED_READY_MARKER_FILE
+                        LOG.info(
+                            "Creating a marker file to report ready: %s", path)
+                        util.write_file(path, "{pid}: {time}\n".format(
+                            pid=os.getpid(), time=time()))
+                        self._report_ready(lease=lease)
+                        report_ready = False
+                    return str(readurl(url, timeout=1, headers=headers,
+                                   exception_cb=exc_cb, infinite=True))
+>>>>>>> cloudinit/sources/DataSourceAzure.py
             except UrlError:
                 # Teardown our EphemeralDHCPv4 context on failure as we retry
                 self._ephemeral_dhcp_ctx.clean_network()
@@ -698,12 +749,56 @@ class DataSourceAzure(sources.DataSource):
            2. Generate a fallback network config that does not include any of
               the blacklisted devices.
         """
+<<<<<<< cloudinit/sources/DataSourceAzure.py
         if not self._network_config or self._network_config == sources.UNSET:
             if self.ds_cfg.get('apply_network_config'):
                 nc_src = self._metadata_imds
             else:
                 nc_src = None
             self._network_config = parse_network_config(nc_src)
+=======
+        blacklist = ['mlx4_core']
+        if not self._network_config:
+            if self._metadata_imds != sources.UNSET:
+                netconfig = {'version': 2, 'ethernets': {}}
+                LOG.debug('Azure: generating network configuration from IMDS')
+                network_metadata = self._metadata_imds['network']
+                for idx, intf in enumerate(network_metadata['interface']):
+                    nicname = 'eth{idx}'.format(idx=idx)
+                    dev_config = {}
+                    for addr4 in intf['ipv4']['ipAddress']:
+                        privateIpv4 = addr4['privateIpAddress']
+                        if privateIpv4:
+                           if dev_config.get('dhcp4', False):
+                               # Append static address config for nic > 1
+                               netPrefix = intf['ipv4']['subnet'][0].get(
+                                   'prefix', '24')
+                               if not dev_config.get('addresses'):
+                                   dev_config['addresses'] = []
+                               dev_config['addresses'].append(
+                                   '{ip}/{prefix}'.format(
+                                       ip=privateIpv4, prefix=netPrefix))
+                           else:
+                               dev_config['dhcp4'] = True
+                    for addr6 in intf['ipv6']['ipAddress']:
+                        privateIpv6 = addr6['privateIpAddress']
+                        if privateIpv6:
+                            dev_config['dhcp6'] = True
+                            break
+                    if dev_config:
+                        mac = ':'.join(re.findall(r'..', intf['macAddress']))
+                        dev_config.update(
+                            {'match': {'macaddress': mac.lower()},
+                             'set-name': nicname})
+                        netconfig['ethernets'][nicname] = dev_config
+            else:
+                LOG.debug('Azure: generating fallback configuration')
+                # generate a network config, blacklist picking mlx4_core devs
+                netconfig = net.generate_fallback_config(
+                    blacklist_drivers=blacklist, config_driver=True)
+
+            self._network_config = netconfig
+>>>>>>> cloudinit/sources/DataSourceAzure.py
         return self._network_config
 
     @property
@@ -1217,6 +1312,7 @@ def load_azure_ds_dir(source_dir):
     return (md, ud, cfg, {'ovf-env.xml': contents})
 
 
+<<<<<<< cloudinit/sources/DataSourceAzure.py
 def parse_network_config(imds_metadata):
     """Convert imds_metadata dictionary to network v2 configuration.
 
@@ -1274,6 +1370,8 @@ def parse_network_config(imds_metadata):
 
 
 @azure_ds_telemetry_reporter
+=======
+>>>>>>> cloudinit/sources/DataSourceAzure.py
 def get_metadata_from_imds(fallback_nic, retries):
     """Query Azure's network metadata service, returning a dictionary.
 
@@ -1282,12 +1380,17 @@ def get_metadata_from_imds(fallback_nic, retries):
         https://docs.microsoft.com/en-us/azure/virtual-machines/windows/instance-metadata-service
 
     @param fallback_nic: String. The name of the nic which requires active
+<<<<<<< cloudinit/sources/DataSourceAzure.py
         network in order to query IMDS.
+=======
+        networ in order to query IMDS.
+>>>>>>> cloudinit/sources/DataSourceAzure.py
     @param retries: The number of retries of the IMDS_URL.
 
     @return: A dict of instance metadata containing compute and network
         info.
     """
+<<<<<<< cloudinit/sources/DataSourceAzure.py
     kwargs = {'logfunc': LOG.debug,
               'msg': 'Crawl of Azure Instance Metadata Service (IMDS)',
               'func': _get_metadata_from_imds, 'args': (retries,)}
@@ -1313,11 +1416,41 @@ def _get_metadata_from_imds(retries):
     try:
         return util.load_json(str(response))
     except json.decoder.JSONDecodeError:
+=======
+    if net.is_up(fallback_nic):
+        return util.log_time(
+            logfunc=LOG.debug,
+            msg='Crawl of Azure Instance Metadata Service (IMDS)',
+            func=_get_metadata_from_imds, args=(retries,))
+    else:
+        with EphemeralDHCPv4(fallback_nic):
+            return util.log_time(
+                logfunc=LOG.debug,
+                msg='Crawl of Azure Instance Metadata Service (IMDS)',
+                func=_get_metadata_from_imds, args=(retries,))
+
+
+def _get_metadata_from_imds(retries):
+    def retry_on_url_error(msg, exception):
+        if isinstance(exception, UrlError):
+            return True  # Continue retries
+        return False  # Stop retries on all other exceptions, including 404s
+
+    url = IMDS_URL + "instance?api-version=2017-12-01"
+    headers = {"Metadata": "true"}
+    response = readurl(
+        url, timeout=1, headers=headers, retries=3,
+        exception_cb=retry_on_url_error)
+    try:
+        return util.load_json(str(response))
+    except:
+>>>>>>> cloudinit/sources/DataSourceAzure.py
         LOG.warning(
             'Ignoring non-json IMDS instance metadata: %s', str(response))
     return {}
 
 
+<<<<<<< cloudinit/sources/DataSourceAzure.py
 @azure_ds_telemetry_reporter
 def maybe_remove_ubuntu_network_config_scripts(paths=None):
     """Remove Azure-specific ubuntu network config for non-primary nics.
@@ -1372,6 +1505,8 @@ def _is_platform_viable(seed_dir):
         return False
 
 
+=======
+>>>>>>> cloudinit/sources/DataSourceAzure.py
 class BrokenAzureDataSource(Exception):
     pass
 
diff --git a/cloudinit/sources/DataSourceBigstep.py b/cloudinit/sources/DataSourceBigstep.py
index 52fff20..c83cd31 100644
--- a/cloudinit/sources/DataSourceBigstep.py
+++ b/cloudinit/sources/DataSourceBigstep.py
@@ -25,7 +25,7 @@ class DataSourceBigstep(sources.DataSource):
         self.vendordata_raw = ""
         self.userdata_raw = ""
 
-    def _get_data(self, apply_filter=False):
+    def _get_data(self, clear_cache=False, apply_filter=False):
         url = get_url_from_file()
         if url is None:
             return False
diff --git a/cloudinit/sources/DataSourceCloudSigma.py b/cloudinit/sources/DataSourceCloudSigma.py
index 2955d3f..9f71700 100644
--- a/cloudinit/sources/DataSourceCloudSigma.py
+++ b/cloudinit/sources/DataSourceCloudSigma.py
@@ -49,7 +49,7 @@ class DataSourceCloudSigma(sources.DataSource):
         LOG.warning("failed to query dmi data for system product name")
         return False
 
-    def _get_data(self):
+    def _get_data(self, clear_cache=False):
         """
         Metadata is the whole server context and /meta/cloud-config is used
         as userdata.
diff --git a/cloudinit/sources/DataSourceCloudStack.py b/cloudinit/sources/DataSourceCloudStack.py
index f185dc7..f76c63e 100644
--- a/cloudinit/sources/DataSourceCloudStack.py
+++ b/cloudinit/sources/DataSourceCloudStack.py
@@ -109,7 +109,7 @@ class DataSourceCloudStack(sources.DataSource):
     def get_config_obj(self):
         return self.cfg
 
-    def _get_data(self):
+    def _get_data(self, clear_cache=False):
         seed_ret = {}
         if util.read_optional_seed(seed_ret, base=(self.seed_dir + "/")):
             self.userdata_raw = seed_ret['user-data']
diff --git a/cloudinit/sources/DataSourceConfigDrive.py b/cloudinit/sources/DataSourceConfigDrive.py
index 571d30d..be32e67 100644
--- a/cloudinit/sources/DataSourceConfigDrive.py
+++ b/cloudinit/sources/DataSourceConfigDrive.py
@@ -54,7 +54,7 @@ class DataSourceConfigDrive(openstack.SourceMixin, sources.DataSource):
         mstr += "[source=%s]" % (self.source)
         return mstr
 
-    def _get_data(self):
+    def _get_data(self, clear_cache=False):
         found = None
         md = {}
         results = {}
diff --git a/cloudinit/sources/DataSourceDigitalOcean.py b/cloudinit/sources/DataSourceDigitalOcean.py
index e0ef665..25e8c87 100644
--- a/cloudinit/sources/DataSourceDigitalOcean.py
+++ b/cloudinit/sources/DataSourceDigitalOcean.py
@@ -47,7 +47,7 @@ class DataSourceDigitalOcean(sources.DataSource):
     def _get_sysinfo(self):
         return do_helper.read_sysinfo()
 
-    def _get_data(self):
+    def _get_data(self, clear_cache=False):
         (is_do, droplet_id) = self._get_sysinfo()
 
         # only proceed if we know we are on DigitalOcean
diff --git a/cloudinit/sources/DataSourceEc2.py b/cloudinit/sources/DataSourceEc2.py
index 5c017bf..d6984a5 100644
--- a/cloudinit/sources/DataSourceEc2.py
+++ b/cloudinit/sources/DataSourceEc2.py
@@ -73,7 +73,19 @@ class DataSourceEc2(sources.DataSource):
         """Return the cloud name as identified during _get_data."""
         return identify_platform()
 
+<<<<<<< cloudinit/sources/DataSourceEc2.py
     def _get_data(self):
+=======
+    def _get_data(self, clear_cache=False):
+        seed_ret = {}
+        if util.read_optional_seed(seed_ret, base=(self.seed_dir + "/")):
+            self.userdata_raw = seed_ret['user-data']
+            self.metadata = seed_ret['meta-data']
+            LOG.debug("Using seeded ec2 data from %s", self.seed_dir)
+            self._cloud_platform = Platforms.SEEDED
+            return True
+
+>>>>>>> cloudinit/sources/DataSourceEc2.py
         strict_mode, _sleep = read_strict_mode(
             util.get_cfg_by_path(self.sys_cfg, STRICT_ID_PATH,
                                  STRICT_ID_DEFAULT), ("warn", None))
diff --git a/cloudinit/sources/DataSourceGCE.py b/cloudinit/sources/DataSourceGCE.py
index d816262..0fd9c77 100644
--- a/cloudinit/sources/DataSourceGCE.py
+++ b/cloudinit/sources/DataSourceGCE.py
@@ -63,7 +63,7 @@ class DataSourceGCE(sources.DataSource):
             BUILTIN_DS_CONFIG])
         self.metadata_address = self.ds_cfg['metadata_url']
 
-    def _get_data(self):
+    def _get_data(self, clear_cache=False):
         ret = util.log_time(
             LOG.debug, 'Crawl of GCE metadata service',
             read_md, kwargs={'address': self.metadata_address})
diff --git a/cloudinit/sources/DataSourceIBMCloud.py b/cloudinit/sources/DataSourceIBMCloud.py
index 21e6ae6..de6db75 100644
--- a/cloudinit/sources/DataSourceIBMCloud.py
+++ b/cloudinit/sources/DataSourceIBMCloud.py
@@ -136,7 +136,7 @@ class DataSourceIBMCloud(sources.DataSource):
         mstr = "%s [%s %s]" % (root, self.platform, self.source)
         return mstr
 
-    def _get_data(self):
+    def _get_data(self, clear_cache=False):
         results = read_md()
         if results is None:
             return False
diff --git a/cloudinit/sources/DataSourceMAAS.py b/cloudinit/sources/DataSourceMAAS.py
index 61aa6d7..d533d55 100644
--- a/cloudinit/sources/DataSourceMAAS.py
+++ b/cloudinit/sources/DataSourceMAAS.py
@@ -61,7 +61,7 @@ class DataSourceMAAS(sources.DataSource):
         root = sources.DataSource.__str__(self)
         return "%s [%s]" % (root, self.base_url)
 
-    def _get_data(self):
+    def _get_data(self, clear_cache=False):
         mcfg = self.ds_cfg
 
         try:
diff --git a/cloudinit/sources/DataSourceNoCloud.py b/cloudinit/sources/DataSourceNoCloud.py
index 8a9e5dd..6a3535e 100644
--- a/cloudinit/sources/DataSourceNoCloud.py
+++ b/cloudinit/sources/DataSourceNoCloud.py
@@ -35,6 +35,7 @@ class DataSourceNoCloud(sources.DataSource):
         root = sources.DataSource.__str__(self)
         return "%s [seed=%s][dsmode=%s]" % (root, self.seed, self.dsmode)
 
+<<<<<<< cloudinit/sources/DataSourceNoCloud.py
     def _get_devices(self, label):
         if util.is_FreeBSD():
             devlist = [
@@ -56,6 +57,9 @@ class DataSourceNoCloud(sources.DataSource):
         return devlist
 
     def _get_data(self):
+=======
+    def _get_data(self, clear_cache=False):
+>>>>>>> cloudinit/sources/DataSourceNoCloud.py
         defaults = {
             "instance-id": "nocloud",
             "dsmode": self.dsmode,
diff --git a/cloudinit/sources/DataSourceNone.py b/cloudinit/sources/DataSourceNone.py
index e625080..65af122 100644
--- a/cloudinit/sources/DataSourceNone.py
+++ b/cloudinit/sources/DataSourceNone.py
@@ -19,7 +19,7 @@ class DataSourceNone(sources.DataSource):
         self.metadata = {}
         self.userdata_raw = ''
 
-    def _get_data(self):
+    def _get_data(self, clear_cache=False):
         # If the datasource config has any provided 'fallback'
         # userdata or metadata, use it...
         if 'userdata_raw' in self.ds_cfg:
diff --git a/cloudinit/sources/DataSourceOVF.py b/cloudinit/sources/DataSourceOVF.py
index 70e7a5c..b3b7608 100644
--- a/cloudinit/sources/DataSourceOVF.py
+++ b/cloudinit/sources/DataSourceOVF.py
@@ -67,7 +67,7 @@ class DataSourceOVF(sources.DataSource):
         root = sources.DataSource.__str__(self)
         return "%s [seed=%s]" % (root, self.seed)
 
-    def _get_data(self):
+    def _get_data(self, clear_cache=False):
         found = []
         md = {}
         ud = ""
diff --git a/cloudinit/sources/DataSourceOpenNebula.py b/cloudinit/sources/DataSourceOpenNebula.py
index 02c9a7b..c8bc4f3 100644
--- a/cloudinit/sources/DataSourceOpenNebula.py
+++ b/cloudinit/sources/DataSourceOpenNebula.py
@@ -44,7 +44,7 @@ class DataSourceOpenNebula(sources.DataSource):
         root = sources.DataSource.__str__(self)
         return "%s [seed=%s][dsmode=%s]" % (root, self.seed, self.dsmode)
 
-    def _get_data(self):
+    def _get_data(self, clear_cache=False):
         defaults = {"instance-id": DEFAULT_IID}
         results = None
         seed = None
diff --git a/cloudinit/sources/DataSourceOpenStack.py b/cloudinit/sources/DataSourceOpenStack.py
index 4a01524..8afc094 100644
--- a/cloudinit/sources/DataSourceOpenStack.py
+++ b/cloudinit/sources/DataSourceOpenStack.py
@@ -115,7 +115,7 @@ class DataSourceOpenStack(openstack.SourceMixin, sources.DataSource):
             self.network_json, known_macs=None)
         return self._network_config
 
-    def _get_data(self):
+    def _get_data(self, clear_cache=False):
         """Crawl metadata, parse and persist that data for this instance.
 
         @return: True when metadata discovered indicates OpenStack datasource.
diff --git a/cloudinit/sources/DataSourceScaleway.py b/cloudinit/sources/DataSourceScaleway.py
index b573b38..76a94db 100644
--- a/cloudinit/sources/DataSourceScaleway.py
+++ b/cloudinit/sources/DataSourceScaleway.py
@@ -190,7 +190,14 @@ class DataSourceScaleway(sources.DataSource):
         self._fallback_interface = None
         self._network_config = None
 
+<<<<<<< cloudinit/sources/DataSourceScaleway.py
     def _crawl_metadata(self):
+=======
+    def _get_data(self, clear_cache=False):
+        if not on_scaleway():
+            return False
+
+>>>>>>> cloudinit/sources/DataSourceScaleway.py
         resp = url_helper.readurl(self.metadata_address,
                                   timeout=self.timeout,
                                   retries=self.retries)
diff --git a/cloudinit/sources/DataSourceSmartOS.py b/cloudinit/sources/DataSourceSmartOS.py
index 32b57cd..58bd235 100644
--- a/cloudinit/sources/DataSourceSmartOS.py
+++ b/cloudinit/sources/DataSourceSmartOS.py
@@ -216,7 +216,7 @@ class DataSourceSmartOS(sources.DataSource):
             os.rename('/'.join([svc_path, 'provisioning']),
                       '/'.join([svc_path, 'provision_success']))
 
-    def _get_data(self):
+    def _get_data(self, clear_cache=False):
         self._init()
 
         md = {}
diff --git a/cloudinit/sources/__init__.py b/cloudinit/sources/__init__.py
index e6966b3..8d3fa64 100644
--- a/cloudinit/sources/__init__.py
+++ b/cloudinit/sources/__init__.py
@@ -19,7 +19,11 @@ from cloudinit.atomic_helper import write_json
 from cloudinit import importer
 from cloudinit import log as logging
 from cloudinit import net
+<<<<<<< cloudinit/sources/__init__.py
 from cloudinit.event import EventType
+=======
+from cloudinit.hotplug import MaintenanceEvent, MAINTENANCE_EVENT_STR
+>>>>>>> cloudinit/sources/__init__.py
 from cloudinit import type_utils
 from cloudinit import user_data as ud
 from cloudinit import util
@@ -158,6 +162,7 @@ class DataSource(object):
     url_timeout = 10    # timeout for each metadata url read attempt
     url_retries = 5     # number of times to retry url upon 404
 
+<<<<<<< cloudinit/sources/__init__.py
     # The datasource defines a set of supported EventTypes during which
     # the datasource can react to changes in metadata and regenerate
     # network configuration on metadata changes.
@@ -180,6 +185,14 @@ class DataSource(object):
     # N-tuple of keypaths or keynames redact from instance-data.json for
     # non-root users
     sensitive_metadata_keys = ('security-credentials',)
+=======
+    # Subclasses can define a mask of supported MaintenanceEvents during
+    # which the datasource will regenerate network_configuration. For example:
+    # network_maintenance_mask = MEvent.BOOT|MEvent.DEVICE_ADD
+
+    # Default behavior, perform no network update for any maintenance event
+    network_maintenance_mask = MaintenanceEvent.NONE
+>>>>>>> cloudinit/sources/__init__.py
 
     def __init__(self, sys_cfg, distro, paths, ud_proc=None):
         self.sys_cfg = sys_cfg
@@ -247,13 +260,31 @@ class DataSource(object):
         if not attr_defaults:
             self._dirty_cache = False
 
-    def get_data(self):
+    def get_data(self, clear_cache=False):
         """Datasources implement _get_data to setup metadata and userdata_raw.
 
         Minimally, the datasource should return a boolean True on success.
+        @param use_cache: Boolean set true to re-use data cache if present.
+           Value of False, will clear any cached data, re-crawling all
+           instance metadata.
         """
+<<<<<<< cloudinit/sources/__init__.py
         self._dirty_cache = True
         return_value = self._get_data()
+=======
+        if clear_cache:
+            if hasattr(self, '_network_config'):
+                # Clear network config property so it is regenerated from md.
+                setattr(self, '_network_config', None)
+            self.userdata = None
+            self.metadata = {}
+            self.userdata_raw = None
+            self.vendordata = None
+            self.vendordata_raw = None
+
+        return_value = self._get_data(clear_cache=clear_cache)
+        json_file = os.path.join(self.paths.run_dir, INSTANCE_JSON_FILE)
+>>>>>>> cloudinit/sources/__init__.py
         if not return_value:
             return return_value
         self.persist_instance_data()
@@ -309,11 +340,18 @@ class DataSource(object):
                    redact_sensitive_keys(processed_data), mode=0o600)
         return True
 
+<<<<<<< cloudinit/sources/__init__.py
     def _get_data(self):
         """Walk metadata sources, process crawled data and save attributes."""
+=======
+    def _get_data(self, clear_cache=False):
+>>>>>>> cloudinit/sources/__init__.py
         raise NotImplementedError(
             'Subclasses of DataSource must implement _get_data which'
-            ' sets self.metadata, vendordata_raw and userdata_raw.')
+            ' sets self.metadata, vendordata_raw and userdata_raw. _get_data'
+            ' must accept an optional clear_cache boolean which will clear'
+            ' any cached metadata, vendordata, userdata etc to ensure a fresh'
+            ' crawl of new metadata')
 
     def get_url_params(self):
         """Return the Datasource's prefered url_read parameters.
@@ -589,6 +627,7 @@ class DataSource(object):
     def get_package_mirror_info(self):
         return self.distro.get_package_mirror_info(data_source=self)
 
+<<<<<<< cloudinit/sources/__init__.py
     def update_metadata(self, source_event_types):
         """Refresh cached metadata if the datasource supports this event.
 
@@ -624,6 +663,21 @@ class DataSource(object):
                 return True
         LOG.debug("Datasource %s not updated for events: %s", self,
                   ', '.join(source_event_types))
+=======
+    def maintain_metadata(self, maintenance_event):
+        """Update datasource metadata if supported for a maintenance event.
+
+        @param maintenance_event: The source hotplug.MaintenanceEvent type
+            observed to which the datasource reacts.
+
+        @return True if metadata was cleared.
+        """
+        if bool(maintenance_event & self.network_maintenance_mask):
+            LOG.debug(
+               "Re-reading datasource metadata due to maintenance event: '%s'",
+               MAINTENANCE_EVENT_STR.get(maintenance_event, maintenance_event))
+            return self.get_data(clear_cache=True)
+>>>>>>> cloudinit/sources/__init__.py
         return False
 
     def check_instance_id(self, sys_cfg):
@@ -652,7 +706,7 @@ class DataSource(object):
         return default
 
     @property
-    def network_config(self):
+    def network_config(self, regenerate=False):
         return None
 
     @property
diff --git a/cloudinit/sources/tests/test_init.py b/cloudinit/sources/tests/test_init.py
index 6378e98..0fb5480 100644
--- a/cloudinit/sources/tests/test_init.py
+++ b/cloudinit/sources/tests/test_init.py
@@ -34,6 +34,7 @@ class DataSourceTestSubclassNet(DataSource):
     def _get_cloud_name(self):
         return 'SubclassCloudName'
 
+<<<<<<< cloudinit/sources/tests/test_init.py
     def _get_data(self):
         if self._custom_metadata:
             self.metadata = self._custom_metadata
@@ -41,6 +42,12 @@ class DataSourceTestSubclassNet(DataSource):
             self.metadata = {'availability_zone': 'myaz',
                              'local-hostname': 'test-subclass-hostname',
                              'region': 'myregion'}
+=======
+    def _get_data(self, clear_cache=False):
+        self.metadata = {'availability_zone': 'myaz',
+                         'local-hostname': 'test-subclass-hostname',
+                         'region': 'myregion'}
+>>>>>>> cloudinit/sources/tests/test_init.py
         if self._custom_userdata:
             self.userdata_raw = self._custom_userdata
         else:
diff --git a/cloudinit/stages.py b/cloudinit/stages.py
index da7d349..358e67f 100644
--- a/cloudinit/stages.py
+++ b/cloudinit/stages.py
@@ -658,12 +658,19 @@ class Init(object):
 
         if self.datasource is not NULL_DATA_SOURCE:
             if not self.is_new_instance():
+<<<<<<< cloudinit/stages.py
                 if not self.datasource.update_metadata([EventType.BOOT]):
                     LOG.debug(
                         "No network config applied. Neither a new instance"
                         " nor datasource network update on '%s' event",
                         EventType.BOOT)
                     return
+=======
+                if not self.datasource.maintain_metadata(MaintenanceEvent.boot):
+                   LOG.debug(
+                       "No network config applied. Neither a new instance nor datasource per-boot network config")
+            return
+>>>>>>> cloudinit/stages.py
 
         LOG.info("Applying network configuration from %s bringup=%s: %s",
                  src, bring_up, netcfg)
diff --git a/tests/unittests/test_datasource/test_azure.py b/tests/unittests/test_datasource/test_azure.py
index f27ef21..e5df86f 100644
--- a/tests/unittests/test_datasource/test_azure.py
+++ b/tests/unittests/test_datasource/test_azure.py
@@ -1,3 +1,4 @@
+<<<<<<< tests/unittests/test_datasource/test_azure.py
 # This file is part of cloud-init. See LICENSE file for license information.
 
 from cloudinit import distros
@@ -1960,3 +1961,5 @@ class TestRandomSeed(CiTestCase):
         self.assertEqual(deserialized['seed'], result)
 
 # vi: ts=4 expandtab
+=======
+>>>>>>> tests/unittests/test_datasource/test_azure.py