diff options
Diffstat (limited to 'cloudinit/sources/DataSourceAzure.py')
| -rw-r--r-- | cloudinit/sources/DataSourceAzure.py | 326 |
1 files changed, 28 insertions, 298 deletions
diff --git a/cloudinit/sources/DataSourceAzure.py b/cloudinit/sources/DataSourceAzure.py index 9dac4c6b..b7d3e5a3 100644 --- a/cloudinit/sources/DataSourceAzure.py +++ b/cloudinit/sources/DataSourceAzure.py @@ -6,7 +6,6 @@ import base64 import crypt -import functools import os import os.path import re @@ -16,8 +15,6 @@ from pathlib import Path from time import sleep, time from typing import Any, Dict, List, Optional -import requests - from cloudinit import dmi from cloudinit import log as logging from cloudinit import net, sources, ssh_util, subp, util @@ -29,6 +26,7 @@ from cloudinit.net.dhcp import ( ) from cloudinit.net.ephemeral import EphemeralDHCPv4 from cloudinit.reporting import events +from cloudinit.sources.azure import imds from cloudinit.sources.helpers import netlink from cloudinit.sources.helpers.azure import ( DEFAULT_WIRESERVER_ENDPOINT, @@ -49,7 +47,7 @@ from cloudinit.sources.helpers.azure import ( report_diagnostic_event, report_failure_to_fabric, ) -from cloudinit.url_helper import UrlError, readurl, retry_on_url_exc +from cloudinit.url_helper import UrlError LOG = logging.getLogger(__name__) @@ -63,34 +61,6 @@ DEFAULT_FS = "ext4" AGENT_SEED_DIR = "/var/lib/waagent" DEFAULT_PROVISIONING_ISO_DEV = "/dev/sr0" -# In the event where the IMDS primary server is not -# available, it takes 1s to fallback to the secondary one -IMDS_TIMEOUT_IN_SECONDS = 2 -IMDS_URL = "http://169.254.169.254/metadata" -IMDS_VER_MIN = "2019-06-01" -IMDS_VER_WANT = "2021-08-01" -IMDS_EXTENDED_VER_MIN = "2021-03-01" -IMDS_RETRY_CODES = ( - 404, # not found (yet) - 410, # gone / unavailable (yet) - 429, # rate-limited/throttled - 500, # server error -) -imds_readurl_exception_callback = functools.partial( - retry_on_url_exc, - retry_codes=IMDS_RETRY_CODES, - retry_instances=( - requests.ConnectionError, - requests.Timeout, - ), -) - - -class MetadataType(Enum): - ALL = "{}/instance".format(IMDS_URL) - NETWORK = "{}/instance/network".format(IMDS_URL) - REPROVISION_DATA = "{}/reprovisiondata".format(IMDS_URL) - class PPSType(Enum): NONE = "None" @@ -593,10 +563,9 @@ class DataSourceAzure(sources.DataSource): except NoDHCPLeaseError: pass + imds_md = {} if self._is_ephemeral_networking_up(): - imds_md = self.get_imds_data_with_api_fallback(retries=10) - else: - imds_md = {} + imds_md = self.get_metadata_from_imds() if not imds_md and ovf_source is None: msg = "No OVF or IMDS available" @@ -619,7 +588,7 @@ class DataSourceAzure(sources.DataSource): md, userdata_raw, cfg, files = self._reprovision() # fetch metadata again as it has changed after reprovisioning - imds_md = self.get_imds_data_with_api_fallback(retries=10) + imds_md = self.get_metadata_from_imds() # Report errors if IMDS network configuration is missing data. self.validate_imds_network_metadata(imds_md=imds_md) @@ -710,6 +679,17 @@ class DataSourceAzure(sources.DataSource): return crawled_data + @azure_ds_telemetry_reporter + def get_metadata_from_imds(self) -> Dict: + try: + return imds.fetch_metadata_with_api_fallback() + except (UrlError, ValueError) as error: + report_diagnostic_event( + "Ignoring IMDS metadata due to: %s" % error, + logger_func=LOG.warning, + ) + return {} + def clear_cached_attrs(self, attr_defaults=()): """Reset any cached class attributes to defaults.""" super(DataSourceAzure, self).clear_cached_attrs(attr_defaults) @@ -795,54 +775,6 @@ class DataSourceAzure(sources.DataSource): ) return True - @azure_ds_telemetry_reporter - def get_imds_data_with_api_fallback( - self, - *, - retries: int, - md_type: MetadataType = MetadataType.ALL, - exc_cb=imds_readurl_exception_callback, - infinite: bool = False, - ) -> dict: - """Fetch metadata from IMDS using IMDS_VER_WANT API version. - - Falls back to IMDS_VER_MIN version if IMDS returns a 400 error code, - indicating that IMDS_VER_WANT is unsupported. - - :return: Parsed metadata dictionary or empty dict on error. - """ - LOG.info("Attempting IMDS api-version: %s", IMDS_VER_WANT) - try: - return get_metadata_from_imds( - retries=retries, - md_type=md_type, - api_version=IMDS_VER_WANT, - exc_cb=exc_cb, - infinite=infinite, - ) - except UrlError as error: - LOG.info("UrlError with IMDS api-version: %s", IMDS_VER_WANT) - # Fall back if HTTP code is 400, otherwise return empty dict. - if error.code != 400: - return {} - - log_msg = "Fall back to IMDS api-version: {}".format(IMDS_VER_MIN) - report_diagnostic_event(log_msg, logger_func=LOG.info) - try: - return get_metadata_from_imds( - retries=retries, - md_type=md_type, - api_version=IMDS_VER_MIN, - exc_cb=exc_cb, - infinite=infinite, - ) - except UrlError as error: - report_diagnostic_event( - "Failed to fetch IMDS metadata: %s" % error, - logger_func=LOG.error, - ) - return {} - def get_instance_id(self): if not self.metadata or "instance-id" not in self.metadata: return self._iid() @@ -1052,82 +984,18 @@ class DataSourceAzure(sources.DataSource): primary nic, then we also get the expected total nic count from IMDS. IMDS will process the request and send a response only for primary NIC. """ - is_primary = False - expected_nic_count = -1 - imds_md = None - metadata_poll_count = 0 - metadata_logging_threshold = 1 - expected_errors_count = 0 - # For now, only a VM's primary NIC can contact IMDS and WireServer. If # DHCP fails for a NIC, we have no mechanism to determine if the NIC is # primary or secondary. In this case, retry DHCP until successful. self._setup_ephemeral_networking(iface=ifname, timeout_minutes=20) - # Retry polling network metadata for a limited duration only when the - # calls fail due to network unreachable error or timeout. - # This is because the platform drops packets going towards IMDS - # when it is not a primary nic. If the calls fail due to other issues - # like 410, 503 etc, then it means we are primary but IMDS service - # is unavailable at the moment. Retry indefinitely in those cases - # since we cannot move on without the network metadata. In the future, - # all this will not be necessary, as a new dhcp option would tell - # whether the nic is primary or not. - def network_metadata_exc_cb(msg, exc): - nonlocal expected_errors_count, metadata_poll_count - nonlocal metadata_logging_threshold - - metadata_poll_count = metadata_poll_count + 1 - - # Log when needed but back off exponentially to avoid exploding - # the log file. - if metadata_poll_count >= metadata_logging_threshold: - metadata_logging_threshold *= 2 - report_diagnostic_event( - "Ran into exception when attempting to reach %s " - "after %d polls." % (msg, metadata_poll_count), - logger_func=LOG.error, - ) - - if isinstance(exc, UrlError): - report_diagnostic_event( - "poll IMDS with %s failed. Exception: %s and code: %s" - % (msg, exc.cause, exc.code), - logger_func=LOG.error, - ) - - # Retry up to a certain limit for both timeout and network - # unreachable errors. - if exc.cause and isinstance( - exc.cause, (requests.Timeout, requests.ConnectionError) - ): - expected_errors_count = expected_errors_count + 1 - return expected_errors_count <= 10 - return True - # Primary nic detection will be optimized in the future. The fact that # primary nic is being attached first helps here. Otherwise each nic # could add several seconds of delay. - try: - imds_md = self.get_imds_data_with_api_fallback( - retries=0, - md_type=MetadataType.NETWORK, - exc_cb=network_metadata_exc_cb, - infinite=True, - ) - except Exception as e: - LOG.warning( - "Failed to get network metadata using nic %s. Attempt to " - "contact IMDS failed with error %s. Assuming this is not the " - "primary nic.", - ifname, - e, - ) - + imds_md = self.get_metadata_from_imds() if imds_md: # Only primary NIC will get a response from IMDS. LOG.info("%s is the primary nic", ifname) - is_primary = True # Set the expected nic count based on the response received. expected_nic_count = len(imds_md["interface"]) @@ -1135,11 +1003,16 @@ class DataSourceAzure(sources.DataSource): "Expected nic count: %d" % expected_nic_count, logger_func=LOG.info, ) - else: - # If we are not the primary nic, then clean the dhcp context. - self._teardown_ephemeral_networking() + return True, expected_nic_count - return is_primary, expected_nic_count + # If we are not the primary nic, then clean the dhcp context. + LOG.warning( + "Failed to fetch IMDS metadata using nic %s. " + "Assuming this is not the primary nic.", + ifname, + ) + self._teardown_ephemeral_networking() + return False, -1 @azure_ds_telemetry_reporter def _wait_for_hot_attached_primary_nic(self, nl_sock): @@ -1229,54 +1102,11 @@ class DataSourceAzure(sources.DataSource): def _poll_imds(self): """Poll IMDS for the new provisioning data until we get a valid response. Then return the returned JSON object.""" - url = "{}?api-version={}".format( - MetadataType.REPROVISION_DATA.value, IMDS_VER_MIN - ) - headers = {"Metadata": "true"} nl_sock = None report_ready = bool( not os.path.isfile(self._reported_ready_marker_file) ) - self.imds_logging_threshold = 1 - self.imds_poll_counter = 1 dhcp_attempts = 0 - reprovision_data = None - - def exc_cb(msg, exception): - if isinstance(exception, UrlError): - if exception.code in (404, 410): - if self.imds_poll_counter == self.imds_logging_threshold: - # Reducing the logging frequency as we are polling IMDS - self.imds_logging_threshold *= 2 - LOG.debug( - "Backing off logging threshold for the same " - "exception to %d", - self.imds_logging_threshold, - ) - report_diagnostic_event( - "poll IMDS with %s failed. " - "Exception: %s and code: %s" - % (msg, exception.cause, exception.code), - logger_func=LOG.debug, - ) - self.imds_poll_counter += 1 - return True - else: - # If we get an exception while trying to call IMDS, we call - # DHCP and setup the ephemeral network to acquire a new IP. - report_diagnostic_event( - "poll IMDS with %s failed. Exception: %s and code: %s" - % (msg, exception.cause, exception.code), - logger_func=LOG.warning, - ) - return False - - report_diagnostic_event( - "poll IMDS failed with an unexpected exception: %s" - % exception, - logger_func=LOG.warning, - ) - return False if report_ready: # Networking must be up for netlink to detect @@ -1338,6 +1168,7 @@ class DataSourceAzure(sources.DataSource): # Teardown old network configuration. self._teardown_ephemeral_networking() + reprovision_data = None while not reprovision_data: if not self._is_ephemeral_networking_up(): dhcp_attempts += 1 @@ -1352,14 +1183,7 @@ class DataSourceAzure(sources.DataSource): parent=azure_ds_reporter, ): try: - reprovision_data = readurl( - url, - timeout=IMDS_TIMEOUT_IN_SECONDS, - headers=headers, - exception_cb=exc_cb, - infinite=True, - log_req_resp=False, - ).contents + reprovision_data = imds.fetch_reprovision_data() except UrlError: self._teardown_ephemeral_networking() continue @@ -1368,10 +1192,6 @@ class DataSourceAzure(sources.DataSource): "attempted dhcp %d times after reuse" % dhcp_attempts, logger_func=LOG.debug, ) - report_diagnostic_event( - "polled imds %d times after reuse" % self.imds_poll_counter, - logger_func=LOG.debug, - ) return reprovision_data @@ -2089,96 +1909,6 @@ def _generate_network_config_from_fallback_config() -> dict: @azure_ds_telemetry_reporter -def get_metadata_from_imds( - retries, - md_type=MetadataType.ALL, - api_version=IMDS_VER_MIN, - exc_cb=imds_readurl_exception_callback, - infinite=False, -): - """Query Azure's instance metadata service, returning a dictionary. - - For more info on IMDS: - https://docs.microsoft.com/en-us/azure/virtual-machines/windows/instance-metadata-service - - @param retries: The number of retries of the IMDS_URL. - @param md_type: Metadata type for IMDS request. - @param api_version: IMDS api-version to use in the request. - - @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, exc_cb, md_type, api_version, infinite), - } - try: - return util.log_time(**kwargs) - except Exception as e: - report_diagnostic_event( - "exception while getting metadata: %s" % e, - logger_func=LOG.warning, - ) - raise - - -@azure_ds_telemetry_reporter -def _get_metadata_from_imds( - retries, - exc_cb, - md_type=MetadataType.ALL, - api_version=IMDS_VER_MIN, - infinite=False, -): - url = "{}?api-version={}".format(md_type.value, api_version) - headers = {"Metadata": "true"} - - # support for extended metadata begins with 2021-03-01 - if api_version >= IMDS_EXTENDED_VER_MIN and md_type == MetadataType.ALL: - url = url + "&extended=true" - - try: - response = readurl( - url, - timeout=IMDS_TIMEOUT_IN_SECONDS, - headers=headers, - retries=retries, - exception_cb=exc_cb, - infinite=infinite, - ) - except Exception as e: - # pylint:disable=no-member - if isinstance(e, UrlError) and e.code == 400: - raise - else: - report_diagnostic_event( - "Ignoring IMDS instance metadata. " - "Get metadata from IMDS failed: %s" % e, - logger_func=LOG.warning, - ) - return {} - try: - from json.decoder import JSONDecodeError - - json_decode_error = JSONDecodeError - except ImportError: - json_decode_error = ValueError - - try: - return util.load_json(response.contents) - except json_decode_error as e: - report_diagnostic_event( - "Ignoring non-json IMDS instance metadata response: %s. " - "Loading non-json IMDS response failed: %s" - % (response.contents, e), - logger_func=LOG.warning, - ) - return {} - - -@azure_ds_telemetry_reporter def maybe_remove_ubuntu_network_config_scripts(paths=None): """Remove Azure-specific ubuntu network config for non-primary nics. |