# Copyright 2013 Rackspace, Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import collections
import importlib.metadata
import ipaddress
import random
import socket
import threading
import time
from urllib import parse as urlparse
import eventlet
from ironic_lib import exception as lib_exc
from ironic_lib import mdns
from oslo_concurrency import processutils
from oslo_config import cfg
from oslo_log import log
from ironic_python_agent.api import app
from ironic_python_agent import config
from ironic_python_agent import encoding
from ironic_python_agent import errors
from ironic_python_agent.extensions import base
from ironic_python_agent import hardware
from ironic_python_agent import inspector
from ironic_python_agent import ironic_api_client
from ironic_python_agent import netutils
from ironic_python_agent import utils
LOG = log.getLogger(__name__)
# Time(in seconds) to wait for any of the interfaces to be up
# before lookup of the node is attempted
NETWORK_WAIT_TIMEOUT = 60
# Time(in seconds) to wait before reattempt
NETWORK_WAIT_RETRY = 5
cfg.CONF.import_group('metrics', 'ironic_lib.metrics_utils')
cfg.CONF.import_group('metrics_statsd', 'ironic_lib.metrics_statsd')
Host = collections.namedtuple('Host', ['hostname', 'port'])
def _time():
"""Wraps time.time() for simpler testing."""
return time.time()
[docs]
class IronicPythonAgentStatus(encoding.Serializable):
"""Represents the status of an agent."""
serializable_fields = ('started_at', 'version')
def __init__(self, started_at, version):
self.started_at = started_at
self.version = version
def _with_jitter(value, min_multiplier, max_multiplier):
interval_multiplier = random.uniform(min_multiplier, max_multiplier)
return value * interval_multiplier
[docs]
class IronicPythonAgentHeartbeater(threading.Thread):
"""Thread that periodically heartbeats to Ironic."""
# If we could wait at most N seconds between heartbeats, we will instead
# wait r x N seconds, where r is a random value between these multipliers.
min_jitter_multiplier = 0.3
max_jitter_multiplier = 0.6
# Error retry between 5 and 10 seconds, at least 12 retries with
# the default ramdisk_heartbeat_timeout of 300 and the worst case interval
# jitter of 0.6.
min_heartbeat_interval = 5
min_error_jitter_multiplier = 1.0
max_error_jitter_multiplier = 2.0
def __init__(self, agent):
"""Initialize the heartbeat thread.
:param agent: an :class:`ironic_python_agent.agent.IronicPythonAgent`
instance.
"""
super(IronicPythonAgentHeartbeater, self).__init__()
self.agent = agent
self.stop_event = threading.Event()
self.api = agent.api_client
self.interval = 0
self.heartbeat_forced = False
self.previous_heartbeat = 0
[docs]
def run(self):
"""Start the heartbeat thread."""
# The first heartbeat happens immediately
LOG.info('Starting heartbeater')
self.agent.set_agent_advertise_addr()
while self._run_next():
eventlet.sleep(0)
def _run_next(self):
# The logic here makes sure we don't wait exactly 5 seconds more or
# less regardless of the current interval since it may cause a
# thundering herd problem when a lot of agents are heartbeating.
# Essentially, if the next heartbeat is due in 2 seconds, don't wait 5.
# But if the next one is scheduled in 2 minutes, do wait 5 to account
# for forced heartbeats.
wait = min(
self.min_heartbeat_interval,
# This operation checks how much of the initially planned interval
# we have still left. Compare with 0 in case we overshoot the goal.
max(0, self.interval - (_time() - self.previous_heartbeat)),
)
if self.stop_event.wait(wait):
return False # done
if self._heartbeat_expected():
self.do_heartbeat()
return True
def _heartbeat_expected(self):
elapsed = _time() - self.previous_heartbeat
# Normal heartbeating
if elapsed >= self.interval:
return True
# Forced heartbeating, but once in 5 seconds
if self.heartbeat_forced and elapsed > self.min_heartbeat_interval:
return True
[docs]
def do_heartbeat(self):
"""Send a heartbeat to Ironic."""
try:
self.api.heartbeat(
uuid=self.agent.get_node_uuid(),
advertise_address=self.agent.advertise_address,
advertise_protocol=self.agent.advertise_protocol,
generated_cert=self.agent.generated_cert,
)
except Exception as exc:
if isinstance(exc, errors.HeartbeatConflictError):
LOG.warning('conflict error sending heartbeat to %s',
self.agent.api_urls)
else:
LOG.exception('error sending heartbeat to %s',
self.agent.api_urls)
self.interval = _with_jitter(self.min_heartbeat_interval,
self.min_error_jitter_multiplier,
self.max_error_jitter_multiplier)
else:
LOG.debug('heartbeat successful')
self.heartbeat_forced = False
self.interval = _with_jitter(self.agent.heartbeat_timeout,
self.min_jitter_multiplier,
self.max_jitter_multiplier)
self.previous_heartbeat = _time()
LOG.info('sleeping before next heartbeat, interval: %s', self.interval)
[docs]
def force_heartbeat(self):
self.heartbeat_forced = True
[docs]
def stop(self):
"""Stop the heartbeat thread."""
LOG.info('stopping heartbeater')
self.stop_event.set()
return self.join()
[docs]
class IronicPythonAgent(base.ExecuteCommandMixin):
"""Class for base agent functionality."""
[docs]
@classmethod
def from_config(cls, conf):
return cls(conf.api_url,
Host(hostname=conf.advertise_host,
port=conf.advertise_port),
Host(hostname=conf.listen_host,
port=conf.listen_port),
conf.ip_lookup_attempts,
conf.ip_lookup_sleep,
conf.network_interface,
conf.lookup_timeout,
conf.lookup_interval,
False,
conf.agent_token,
conf.hardware_initialization_delay,
conf.advertise_protocol)
def __init__(self, api_url, advertise_address, listen_address,
ip_lookup_attempts, ip_lookup_sleep, network_interface,
lookup_timeout, lookup_interval, standalone, agent_token,
hardware_initialization_delay=0, advertise_protocol='http'):
super(IronicPythonAgent, self).__init__()
if bool(cfg.CONF.keyfile) != bool(cfg.CONF.certfile):
LOG.warning("Only one of 'keyfile' and 'certfile' options is "
"defined in config file. Its value will be ignored.")
self.ext_mgr = base.init_ext_manager(self)
if (not api_url or api_url == 'mdns') and not standalone:
try:
api_url, params = mdns.get_endpoint('baremetal')
except lib_exc.ServiceLookupFailure:
if api_url:
# mDNS explicitly requested, report failure.
raise
else:
# implicit fallback to mDNS, do not fail (maybe we're only
# running inspection).
LOG.warning('Could not get baremetal endpoint from mDNS, '
'will not heartbeat')
else:
config.override(params)
if api_url:
self.api_urls = list(filter(None, api_url.split(',')))
else:
self.api_urls = None
if self.api_urls:
self.api_client = ironic_api_client.APIClient(self.api_urls)
self.heartbeater = IronicPythonAgentHeartbeater(self)
self.listen_address = listen_address
self.advertise_address = advertise_address
self.advertise_protocol = advertise_protocol
self.version = importlib.metadata.version('ironic-python-agent')
self.api = app.Application(self, cfg.CONF)
self.heartbeat_timeout = None
self.started_at = None
self.node = None
# lookup timeout in seconds
self.lookup_timeout = lookup_timeout
self.lookup_interval = lookup_interval
self.ip_lookup_attempts = ip_lookup_attempts
self.ip_lookup_sleep = ip_lookup_sleep
self.network_interface = network_interface
self.standalone = standalone
self.hardware_initialization_delay = hardware_initialization_delay
# IPA will stop serving requests and exit after this is set to False
self.serve_api = True
# Together with serve_api, this option allows locking down the system
# before IPA stops.
self.lockdown = False
self.agent_token = agent_token
# Allows this to be turned on by the conductor while running,
# in the event of long running ramdisks where the conductor
# got upgraded somewhere along the way.
self.agent_token_required = cfg.CONF.agent_token_required
self.generated_cert = None
[docs]
def get_status(self):
"""Retrieve a serializable status.
:returns: a :class:`ironic_python_agent.agent.IronicPythonAgent`
instance describing the agent's status.
"""
return IronicPythonAgentStatus(
started_at=self.started_at,
version=self.version
)
[docs]
def validate_agent_token(self, token):
# We did not get a token, i.e. None and
# we've previously seen a token, which is
# a mid-cluster upgrade case with long-running ramdisks.
if (not token and self.agent_token
and not self.agent_token_required):
# TODO(TheJulia): Rip this out during or after the V cycle.
LOG.warning('Agent token for requests are not required '
'by the conductor, yet we received a token. '
'Cluster may be mid-upgrade. Support to '
'not fail in this condition will be removed in '
'the Victoria development cycle.')
# Tell the API everything is okay.
return True
return self.agent_token == token
def _get_route_source(self, dest):
"""Get the IP address to send packages to destination."""
try:
out, _err = utils.execute('ip', 'route', 'get', dest)
except (EnvironmentError, processutils.ProcessExecutionError) as e:
LOG.warning('Cannot get route to host %(dest)s: %(err)s',
{'dest': dest, 'err': e})
return
try:
source = out.strip().split('\n')[0].split('src')[1].split()[0]
except IndexError:
LOG.warning('No route to host %(dest)s, route record: %(rec)s',
{'dest': dest, 'rec': out})
return
try:
if ipaddress.ip_address(source).is_link_local:
LOG.info('Ignoring link-local source to %(dest)s: %(rec)s',
{'dest': dest, 'rec': out})
return
except ValueError as exc:
LOG.warning('Invalid IP address %(addr)s returned as a route '
'to host %(dest)s: %(err)s',
{'dest': dest, 'addr': source, 'err': exc})
return source
def _find_routable_addr(self):
ips = set()
for api_url in self.api_urls:
ironic_host = urlparse.urlparse(api_url).hostname
# Try resolving it in case it's not an IP address
try:
addrs = socket.getaddrinfo(ironic_host, 0)
except socket.gaierror:
LOG.debug('Could not resolve %s, maybe no DNS', ironic_host)
ips.add(ironic_host)
continue
ips.update(addr for _, _, _, _, (addr, *_) in addrs)
for attempt in range(self.ip_lookup_attempts):
for ironic_host in ips:
found_ip = self._get_route_source(ironic_host)
if found_ip:
return found_ip
time.sleep(self.ip_lookup_sleep)
[docs]
def set_agent_advertise_addr(self):
"""Set advertised IP address for the agent, if not already set.
If agent's advertised IP address is still default (None), try to
find a better one. If the agent's network interface is None, replace
that as well.
:raises: LookupAgentIPError if an IP address could not be found
"""
if self.advertise_address.hostname is not None:
return
found_ip = None
if self.network_interface is not None:
# TODO(dtantsur): deprecate this
found_ip = hardware.dispatch_to_managers('get_ipv4_addr',
self.network_interface)
else:
found_ip = self._find_routable_addr()
if found_ip:
self.advertise_address = Host(hostname=found_ip,
port=self.advertise_address.port)
else:
raise errors.LookupAgentIPError('Agent could not find a valid IP '
'address.')
[docs]
def get_node_uuid(self):
"""Get UUID for Ironic node.
If the agent has not yet heartbeated to Ironic, it will not have
the UUID and this will raise an exception.
:returns: A string containing the UUID for the Ironic node.
:raises: UnknownNodeError if UUID is unknown.
"""
if self.node is None or 'uuid' not in self.node:
raise errors.UnknownNodeError()
return self.node['uuid']
[docs]
def list_command_results(self):
"""Get a list of command results.
:returns: list of :class:`ironic_python_agent.extensions.base.
BaseCommandResult` objects.
"""
return list(self.command_results.values())
[docs]
def get_command_result(self, result_id):
"""Get a specific command result by ID.
:returns: a :class:`ironic_python_agent.extensions.base.
BaseCommandResult` object.
:raises: RequestedObjectNotFoundError if command with the given ID
is not found.
"""
try:
return self.command_results[result_id]
except KeyError:
raise errors.RequestedObjectNotFoundError('Command Result',
result_id)
[docs]
def force_heartbeat(self):
if not self.standalone:
self.heartbeater.force_heartbeat()
def _wait_for_interface(self):
"""Wait until at least one interface is up."""
wait_till = time.time() + NETWORK_WAIT_TIMEOUT
while time.time() < wait_till:
interfaces = hardware.dispatch_to_managers(
'list_network_interfaces')
if not any(ifc.mac_address for ifc in interfaces):
LOG.debug('Network is not up yet. '
'No valid interfaces found, retrying ...')
time.sleep(NETWORK_WAIT_RETRY)
else:
break
else:
LOG.warning("No valid network interfaces found. "
"Node lookup will probably fail.")
def _start_auto_tls(self):
# NOTE(dtantsur): if listen_tls is True, assume static TLS
# configuration and don't auto-generate anything.
if cfg.CONF.listen_tls or not cfg.CONF.enable_auto_tls:
LOG.debug('Automated TLS is disabled')
return None, None
if not self.api_urls or not self.api_client.supports_auto_tls():
LOG.warning('Ironic does not support automated TLS')
return None, None
self.set_agent_advertise_addr()
LOG.info('Generating TLS parameters automatically for IP %s',
self.advertise_address.hostname)
tls_info = hardware.dispatch_to_managers(
'generate_tls_certificate', self.advertise_address.hostname)
self.generated_cert = tls_info.text
self.advertise_protocol = 'https'
return tls_info.path, tls_info.private_key_path
[docs]
def serve_ipa_api(self):
"""Serve the API until an extension terminates it."""
cert_file, key_file = self._start_auto_tls()
self.api.start(cert_file, key_file)
if not self.standalone and self.api_urls:
# Don't start heartbeating until the server is listening
self.heartbeater.start()
try:
while self.serve_api:
eventlet.sleep(0.1)
except KeyboardInterrupt:
LOG.info('Caught keyboard interrupt, exiting')
self.api.stop()
[docs]
def process_lookup_data(self, content):
"""Update agent configuration from lookup data."""
self.node = content['node']
LOG.info('Lookup succeeded, node UUID is %s',
self.node['uuid'])
hardware.cache_node(self.node)
self.heartbeat_timeout = content['config']['heartbeat_timeout']
# Update config with values from Ironic
config = content.get('config', {})
if config.get('metrics'):
for opt, val in config.items():
setattr(cfg.CONF.metrics, opt, val)
if config.get('metrics_statsd'):
for opt, val in config.items():
setattr(cfg.CONF.metrics_statsd, opt, val)
if config.get('disable_deep_image_inspection') is not None:
cfg.CONF.set_override('disable_deep_image_inspection',
config['disable_deep_image_inspection'])
if config.get('permitted_image_formats') is not None:
cfg.CONF.set_override('permitted_image_formats',
config['permitted_image_formats'])
md5_allowed = config.get('agent_md5_checksum_enable')
if md5_allowed is not None:
cfg.CONF.set_override('md5_enabled', md5_allowed)
if config.get('agent_token_required'):
self.agent_token_required = True
token = config.get('agent_token')
if token:
if len(token) >= 32:
LOG.debug('Agent token recorded as designated by '
'the ironic installation.')
self.agent_token = token
# set with-in the API client.
if not self.standalone:
self.api_client.agent_token = token
elif token == '******':
LOG.warning('The agent token has already been '
'retrieved. IPA may not operate as '
'intended and the deployment may fail '
'depending on settings in the ironic '
'deployment.')
if not self.agent_token and self.agent_token_required:
LOG.error('Ironic is signaling that agent tokens '
'are required, however we do not have '
'a token on file. '
'This is likely **FATAL**.')
else:
LOG.info('An invalid token was received.')
if self.agent_token and not self.standalone:
# Explicitly set the token in our API client before
# starting heartbeat operations.
self.api_client.agent_token = self.agent_token
[docs]
def run(self):
"""Run the Ironic Python Agent."""
LOG.info('Starting ironic-python-agent version: %s',
self.version)
# Get the UUID so we can heartbeat to Ironic. Raises LookupNodeError
# if there is an issue (uncaught, restart agent)
self.started_at = _time()
# Attempt to sync the software clock
utils.sync_clock(ignore_errors=True)
# Cached hw managers at runtime, not load time. See bug 1490008.
hardware.get_managers()
# Operator-settable delay before hardware actually comes up.
# Helps with slow RAID drivers - see bug 1582797.
if self.hardware_initialization_delay > 0:
LOG.info('Waiting %d seconds before proceeding',
self.hardware_initialization_delay)
time.sleep(self.hardware_initialization_delay)
if not self.standalone:
# Inspection should be started before call to lookup, otherwise
# lookup will fail due to unknown MAC.
uuid = None
# We can't try to inspect or heartbeat until we have valid
# interfaces to perform those actions over.
self._wait_for_interface()
if self.api_urls or cfg.CONF.inspection_callback_url:
try:
# Attempt inspection. This may fail, and previously
# an error would be logged.
uuid = inspector.inspect()
except errors.InspectionError as e:
LOG.error('Failed to perform inspection: %s', e)
if self.api_urls:
content = self.api_client.lookup_node(
hardware_info=hardware.list_hardware_info(use_cache=True),
timeout=self.lookup_timeout,
starting_interval=self.lookup_interval,
node_uuid=uuid)
LOG.debug('Received lookup results: %s', content)
self.process_lookup_data(content)
# Save the API url in case we need it later.
hardware.save_api_client(
self.api_client, self.lookup_timeout,
self.lookup_interval)
elif cfg.CONF.inspection_callback_url:
LOG.info('No ipa-api-url configured, Heartbeat and lookup '
'skipped for inspector.')
else:
# NOTE(TheJulia): Once communication flow capability is
# able to be driven solely from the conductor, this is no
# longer a major issue.
LOG.error('Neither ipa-api-url nor inspection_callback_url'
'found, please check your pxe append parameters.')
self.serve_ipa_api()
if not self.standalone and self.api_urls:
self.heartbeater.stop()
if self.lockdown:
self._lockdown_system()
LOG.info('System locked down, looping forever to avoid a service '
'restart')
while True:
time.sleep(100)
def _lockdown_system(self):
LOG.info('Locking down system after the API stopped')
# NOTE(dtantsur): not going through hardware managers here to minimize
# the amount of operations.
for iface in netutils.list_interfaces():
try:
utils.execute('ip', 'link', 'set', iface, 'down')
except Exception as exc:
LOG.warning('Could not bring down interface %s: %s',
iface, exc)
