def get_metadata_from_imds(fallback_nic, retries):
"""Query Azure's network metadata service, returning a dictionary.
If network is not up, setup ephemeral dhcp on fallback_nic to talk to the
IMDS. For more info on IMDS:
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
network in order to query IMDS.
@param retries: The number of retries of the IMDS_URL.
@return: A dict of instance metadata containing compute and network
info.
"""
kwargs = {
'logfunc': LOG.debug,
'msg': 'Crawl of Azure Instance Metadata Service (IMDS)',
'func': _get_metadata_from_imds,
'args': (retries, )
}
if net.is_up(fallback_nic):
return util.log_time(**kwargs)
else:
with EphemeralDHCPv4(fallback_nic):
return util.log_time(**kwargs)
def test_is_up_false(self):
"""is_up is False if sys/net/devname/operstate is 'down' or invalid."""
for state in ['down', 'incomprehensible']:
write_file(os.path.join(self.sysdir, 'eth0', 'operstate'), state)
self.assertFalse(net.is_up('eth0'))
def test_is_up_true(self):
"""is_up is True if sys/net/devname/operstate is 'up' or 'unknown'."""
for state in ['up', 'unknown']:
write_file(os.path.join(self.sysdir, 'eth0', 'operstate'), state)
self.assertTrue(net.is_up('eth0'))
def crawl_metadata(self):
"""Walk all instance metadata sources returning a dict on success.
@return: A dictionary of any metadata content for this instance.
@raise: InvalidMetaDataException when the expected metadata service is
unavailable, broken or disabled.
"""
crawled_data = {}
# 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
ddir = self.ds_cfg['data_dir']
candidates = [self.seed_dir]
if os.path.isfile(REPROVISION_MARKER_FILE):
candidates.insert(0, "IMDS")
candidates.extend(list_possible_azure_ds_devs())
if ddir:
candidates.append(ddir)
found = None
reprovision = False
for cdev in candidates:
try:
if cdev == "IMDS":
ret = None
reprovision = True
elif cdev.startswith("/dev/"):
if util.is_FreeBSD():
ret = util.mount_cb(cdev,
load_azure_ds_dir,
mtype="udf",
sync=False)
else:
ret = util.mount_cb(cdev, load_azure_ds_dir)
else:
ret = load_azure_ds_dir(cdev)
except NonAzureDataSource:
continue
except BrokenAzureDataSource as exc:
msg = 'BrokenAzureDataSource: %s' % exc
raise sources.InvalidMetaDataException(msg)
except util.MountFailedError:
LOG.warning("%s was not mountable", cdev)
continue
perform_reprovision = reprovision or self._should_reprovision(ret)
if perform_reprovision:
if util.is_FreeBSD():
msg = "Free BSD is not supported for PPS VMs"
LOG.error(msg)
raise sources.InvalidMetaDataException(msg)
ret = self._reprovision()
imds_md = get_metadata_from_imds(self.fallback_interface,
retries=10)
(md, userdata_raw, cfg, files) = ret
self.seed = cdev
crawled_data.update({
'cfg':
cfg,
'files':
files,
'metadata':
util.mergemanydict([md, {
'imds': imds_md
}]),
'userdata_raw':
userdata_raw
})
found = cdev
LOG.debug("found datasource in %s", cdev)
break
if not found:
raise sources.InvalidMetaDataException('No Azure metadata found')
if found == ddir:
LOG.debug("using files cached in %s", ddir)
seed = _get_random_seed()
if seed:
crawled_data['metadata']['random_seed'] = seed
crawled_data['metadata']['instance-id'] = util.read_dmi_data(
'system-uuid')
if perform_reprovision:
LOG.info("Reporting ready to Azure after getting ReprovisionData")
use_cached_ephemeral = (net.is_up(self.fallback_interface) and
getattr(self, '_ephemeral_dhcp_ctx', None))
if use_cached_ephemeral:
self._report_ready(lease=self._ephemeral_dhcp_ctx.lease)
self._ephemeral_dhcp_ctx.clean_network() # Teardown ephemeral
else:
with EphemeralDHCPv4() as lease:
self._report_ready(lease=lease)
return crawled_data
def is_up(self, devname: DeviceName) -> bool:
return net.is_up(devname)
def test_is_up_false(self):
"""is_up is False if sys/net/devname/operstate is 'down' or invalid."""
for state in ['down', 'incomprehensible']:
write_file(os.path.join(self.sysdir, 'eth0', 'operstate'), state)
self.assertFalse(net.is_up('eth0'))
def test_is_up_true(self):
"""is_up is True if sys/net/devname/operstate is 'up' or 'unknown'."""
for state in ['up', 'unknown']:
write_file(os.path.join(self.sysdir, 'eth0', 'operstate'), state)
self.assertTrue(net.is_up('eth0'))
