예제 #1
0
def _main_greenlet(config):
    """
    The root of our tree of greenlets.  Responsible for restarting
    its children if desired.
    """
    try:
        _log.info("Connecting to etcd to get our configuration.")
        hosts_ipset_v4 = IpsetActor(HOSTS_IPSET_V4)

        etcd_api = EtcdAPI(config, hosts_ipset_v4)
        etcd_api.start()
        # Ask the EtcdAPI to fill in the global config object before we
        # proceed.  We don't yet support config updates.
        config_loaded = etcd_api.load_config(async=False)
        config_loaded.wait()

        _log.info("Main greenlet: Configuration loaded, starting remaining "
                  "actors...")
        v4_filter_updater = IptablesUpdater("filter", ip_version=4)
        v4_nat_updater = IptablesUpdater("nat", ip_version=4)
        v4_ipset_mgr = IpsetManager(IPV4)
        v4_masq_manager = MasqueradeManager(IPV4, v4_nat_updater)
        v4_rules_manager = RulesManager(4, v4_filter_updater, v4_ipset_mgr)
        v4_dispatch_chains = DispatchChains(config, 4, v4_filter_updater)
        v4_ep_manager = EndpointManager(config,
                                        IPV4,
                                        v4_filter_updater,
                                        v4_dispatch_chains,
                                        v4_rules_manager)

        v6_filter_updater = IptablesUpdater("filter", ip_version=6)
        v6_ipset_mgr = IpsetManager(IPV6)
        v6_rules_manager = RulesManager(6, v6_filter_updater, v6_ipset_mgr)
        v6_dispatch_chains = DispatchChains(config, 6, v6_filter_updater)
        v6_ep_manager = EndpointManager(config,
                                        IPV6,
                                        v6_filter_updater,
                                        v6_dispatch_chains,
                                        v6_rules_manager)

        update_splitter = UpdateSplitter(config,
                                         [v4_ipset_mgr, v6_ipset_mgr],
                                         [v4_rules_manager, v6_rules_manager],
                                         [v4_ep_manager, v6_ep_manager],
                                         [v4_filter_updater,
                                          v6_filter_updater],
                                         v4_masq_manager)
        iface_watcher = InterfaceWatcher(update_splitter)

        _log.info("Starting actors.")
        hosts_ipset_v4.start()
        update_splitter.start()

        v4_filter_updater.start()
        v4_nat_updater.start()
        v4_ipset_mgr.start()
        v4_masq_manager.start()
        v4_rules_manager.start()
        v4_dispatch_chains.start()
        v4_ep_manager.start()

        v6_filter_updater.start()
        v6_ipset_mgr.start()
        v6_rules_manager.start()
        v6_dispatch_chains.start()
        v6_ep_manager.start()

        iface_watcher.start()

        top_level_actors = [
            hosts_ipset_v4,
            update_splitter,

            v4_nat_updater,
            v4_filter_updater,
            v4_nat_updater,
            v4_ipset_mgr,
            v4_masq_manager,
            v4_rules_manager,
            v4_dispatch_chains,
            v4_ep_manager,

            v6_filter_updater,
            v6_ipset_mgr,
            v6_rules_manager,
            v6_dispatch_chains,
            v6_ep_manager,

            iface_watcher,
            etcd_api,
        ]

        monitored_items = [actor.greenlet for actor in top_level_actors]

        # Install the global rules before we start polling for updates.
        _log.info("Installing global rules.")
        install_global_rules(config, v4_filter_updater, v6_filter_updater,
                             v4_nat_updater)

        # Start polling for updates. These kicks make the actors poll
        # indefinitely.
        _log.info("Starting polling for interface and etcd updates.")
        f = iface_watcher.watch_interfaces(async=True)
        monitored_items.append(f)
        etcd_api.start_watch(update_splitter, async=True)

        # Register a SIG_USR handler to trigger a diags dump.
        def dump_top_level_actors(log):
            for a in top_level_actors:
                # The output will include queue length and the like.
                log.info("%s", a)
        futils.register_diags("Top-level actors", dump_top_level_actors)
        try:
            gevent.signal(signal.SIGUSR1, functools.partial(futils.dump_diags))
        except AttributeError:
            # It doesn't matter too much if we fail to do this.
            _log.warning("Unable to install diag dump handler")
            pass

        # Wait for something to fail.
        _log.info("All top-level actors started, waiting on failures...")
        stopped_greenlets_iter = gevent.iwait(monitored_items)

        stopped_greenlet = next(stopped_greenlets_iter)
        try:
            stopped_greenlet.get()
        except Exception:
            _log.exception("Greenlet failed: %s", stopped_greenlet)
            raise
        else:
            _log.error("Greenlet %s unexpectedly returned.", stopped_greenlet)
            raise AssertionError("Greenlet unexpectedly returned")
    except:
        _log.exception("Exception killing main greenlet")
        raise
예제 #2
0
def _main_greenlet(config):
    """
    The root of our tree of greenlets.  Responsible for restarting
    its children if desired.
    """
    try:
        _log.info("Connecting to etcd to get our configuration.")
        hosts_ipset_v4 = IpsetActor(HOSTS_IPSET_V4)

        etcd_api = EtcdAPI(config, hosts_ipset_v4)
        etcd_api.start()
        # Ask the EtcdAPI to fill in the global config object before we
        # proceed.  We don't yet support config updates.
        config_loaded = etcd_api.load_config(async=False)
        config_loaded.wait()

        # Ensure the Kernel's global options are correctly configured for
        # Calico.
        devices.configure_global_kernel_config()

        _log.info("Main greenlet: Configuration loaded, starting remaining "
                  "actors...")
        v4_filter_updater = IptablesUpdater("filter", ip_version=4,
                                            config=config)
        v4_nat_updater = IptablesUpdater("nat", ip_version=4, config=config)
        v4_ipset_mgr = IpsetManager(IPV4)
        v4_masq_manager = MasqueradeManager(IPV4, v4_nat_updater)
        v4_rules_manager = RulesManager(4, v4_filter_updater, v4_ipset_mgr)
        v4_dispatch_chains = DispatchChains(config, 4, v4_filter_updater)
        v4_ep_manager = EndpointManager(config,
                                        IPV4,
                                        v4_filter_updater,
                                        v4_dispatch_chains,
                                        v4_rules_manager,
                                        etcd_api.status_reporter)

        v6_raw_updater = IptablesUpdater("raw", ip_version=6, config=config)
        v6_filter_updater = IptablesUpdater("filter", ip_version=6,
                                            config=config)
        v6_ipset_mgr = IpsetManager(IPV6)
        v6_rules_manager = RulesManager(6, v6_filter_updater, v6_ipset_mgr)
        v6_dispatch_chains = DispatchChains(config, 6, v6_filter_updater)
        v6_ep_manager = EndpointManager(config,
                                        IPV6,
                                        v6_filter_updater,
                                        v6_dispatch_chains,
                                        v6_rules_manager,
                                        etcd_api.status_reporter)

        update_splitter = UpdateSplitter(config,
                                         [v4_ipset_mgr, v6_ipset_mgr],
                                         [v4_rules_manager, v6_rules_manager],
                                         [v4_ep_manager, v6_ep_manager],
                                         [v4_filter_updater,
                                          v6_filter_updater,
                                          v6_raw_updater,
                                          v4_nat_updater],
                                         v4_masq_manager)
        iface_watcher = InterfaceWatcher(update_splitter)

        _log.info("Starting actors.")
        hosts_ipset_v4.start()
        update_splitter.start()

        v4_filter_updater.start()
        v4_nat_updater.start()
        v4_ipset_mgr.start()
        v4_masq_manager.start()
        v4_rules_manager.start()
        v4_dispatch_chains.start()
        v4_ep_manager.start()

        v6_raw_updater.start()
        v6_filter_updater.start()
        v6_ipset_mgr.start()
        v6_rules_manager.start()
        v6_dispatch_chains.start()
        v6_ep_manager.start()

        iface_watcher.start()

        top_level_actors = [
            hosts_ipset_v4,
            update_splitter,

            v4_nat_updater,
            v4_filter_updater,
            v4_nat_updater,
            v4_ipset_mgr,
            v4_masq_manager,
            v4_rules_manager,
            v4_dispatch_chains,
            v4_ep_manager,

            v6_raw_updater,
            v6_filter_updater,
            v6_ipset_mgr,
            v6_rules_manager,
            v6_dispatch_chains,
            v6_ep_manager,

            iface_watcher,
            etcd_api,
        ]

        monitored_items = [actor.greenlet for actor in top_level_actors]

        # Install the global rules before we start polling for updates.
        _log.info("Installing global rules.")
        install_global_rules(config, v4_filter_updater, v6_filter_updater,
                             v4_nat_updater, v6_raw_updater)

        # Start polling for updates. These kicks make the actors poll
        # indefinitely.
        _log.info("Starting polling for interface and etcd updates.")
        f = iface_watcher.watch_interfaces(async=True)
        monitored_items.append(f)
        etcd_api.start_watch(update_splitter, async=True)

        # Register a SIG_USR handler to trigger a diags dump.
        def dump_top_level_actors(log):
            for a in top_level_actors:
                # The output will include queue length and the like.
                log.info("%s", a)
        futils.register_diags("Top-level actors", dump_top_level_actors)
        futils.register_process_statistics()
        try:
            gevent.signal(signal.SIGUSR1, functools.partial(futils.dump_diags))
        except AttributeError:
            # It doesn't matter too much if we fail to do this.
            _log.warning("Unable to install diag dump handler")
            pass

        # Wait for something to fail.
        _log.info("All top-level actors started, waiting on failures...")
        stopped_greenlets_iter = gevent.iwait(monitored_items)

        stopped_greenlet = next(stopped_greenlets_iter)
        try:
            stopped_greenlet.get()
        except Exception:
            _log.exception("Greenlet failed: %s", stopped_greenlet)
            raise
        else:
            _log.error("Greenlet %s unexpectedly returned.", stopped_greenlet)
            raise AssertionError("Greenlet unexpectedly returned")
    except:
        _log.exception("Exception killing main greenlet")
        raise
예제 #3
0
파일: felix.py 프로젝트: tjtunnell/calico
def _main_greenlet(config):
    """
    The root of our tree of greenlets.  Responsible for restarting
    its children if desired.
    """
    try:
        _log.info("Connecting to etcd to get our configuration.")
        hosts_ipset_v4 = IpsetActor(HOSTS_IPSET_V4)

        etcd_api = EtcdAPI(config, hosts_ipset_v4)
        etcd_api.start()
        # Ask the EtcdAPI to fill in the global config object before we
        # proceed.  We don't yet support config updates.
        config_loaded = etcd_api.load_config(async=False)
        config_loaded.wait()

        # Ensure the Kernel's global options are correctly configured for
        # Calico.
        devices.configure_global_kernel_config()

        _log.info("Main greenlet: Configuration loaded, starting remaining " "actors...")

        monitored_items = []
        if config.PROM_METRICS_ENABLED:
            httpd = HTTPServer(("0.0.0.0", config.PROM_METRICS_PORT), MetricsHandler)
            stats_server = gevent.Greenlet(httpd.serve_forever)
            stats_server.start()
            monitored_items.append(stats_server)

        v4_filter_updater = IptablesUpdater("filter", ip_version=4, config=config)
        v4_nat_updater = IptablesUpdater("nat", ip_version=4, config=config)
        v4_ipset_mgr = IpsetManager(IPV4, config)
        v4_masq_manager = MasqueradeManager(IPV4, v4_nat_updater)
        v4_rules_manager = RulesManager(config, 4, v4_filter_updater, v4_ipset_mgr)
        v4_dispatch_chains = DispatchChains(config, 4, v4_filter_updater)
        v4_fip_manager = FloatingIPManager(config, 4, v4_nat_updater)
        v4_ep_manager = EndpointManager(
            config,
            IPV4,
            v4_filter_updater,
            v4_dispatch_chains,
            v4_rules_manager,
            v4_fip_manager,
            etcd_api.status_reporter,
        )

        cleanup_updaters = [v4_filter_updater, v4_nat_updater]
        cleanup_ip_mgrs = [v4_ipset_mgr]
        update_splitter_args = [v4_ipset_mgr, v4_rules_manager, v4_ep_manager, v4_masq_manager, v4_nat_updater]

        v6_enabled = os.path.exists("/proc/sys/net/ipv6")
        if v6_enabled:
            v6_raw_updater = IptablesUpdater("raw", ip_version=6, config=config)
            v6_filter_updater = IptablesUpdater("filter", ip_version=6, config=config)
            v6_nat_updater = IptablesUpdater("nat", ip_version=6, config=config)
            v6_ipset_mgr = IpsetManager(IPV6, config)
            v6_rules_manager = RulesManager(config, 6, v6_filter_updater, v6_ipset_mgr)
            v6_dispatch_chains = DispatchChains(config, 6, v6_filter_updater)
            v6_fip_manager = FloatingIPManager(config, 6, v6_nat_updater)
            v6_ep_manager = EndpointManager(
                config,
                IPV6,
                v6_filter_updater,
                v6_dispatch_chains,
                v6_rules_manager,
                v6_fip_manager,
                etcd_api.status_reporter,
            )
            cleanup_updaters.append(v6_filter_updater)
            cleanup_ip_mgrs.append(v6_ipset_mgr)
            update_splitter_args += [v6_ipset_mgr, v6_rules_manager, v6_ep_manager, v6_raw_updater, v6_nat_updater]

        cleanup_mgr = CleanupManager(config, cleanup_updaters, cleanup_ip_mgrs)
        update_splitter_args.append(cleanup_mgr)
        update_splitter = UpdateSplitter(update_splitter_args)
        iface_watcher = InterfaceWatcher(update_splitter)

        _log.info("Starting actors.")
        hosts_ipset_v4.start()
        cleanup_mgr.start()

        v4_filter_updater.start()
        v4_nat_updater.start()
        v4_ipset_mgr.start()
        v4_masq_manager.start()
        v4_rules_manager.start()
        v4_dispatch_chains.start()
        v4_ep_manager.start()
        v4_fip_manager.start()

        if v6_enabled:
            v6_raw_updater.start()
            v6_filter_updater.start()
            v6_ipset_mgr.start()
            v6_nat_updater.start()
            v6_rules_manager.start()
            v6_dispatch_chains.start()
            v6_ep_manager.start()
            v6_fip_manager.start()

        iface_watcher.start()

        top_level_actors = [
            hosts_ipset_v4,
            cleanup_mgr,
            v4_filter_updater,
            v4_nat_updater,
            v4_ipset_mgr,
            v4_masq_manager,
            v4_rules_manager,
            v4_dispatch_chains,
            v4_ep_manager,
            v4_fip_manager,
            iface_watcher,
            etcd_api,
        ]

        if v6_enabled:
            top_level_actors += [
                v6_raw_updater,
                v6_filter_updater,
                v6_nat_updater,
                v6_ipset_mgr,
                v6_rules_manager,
                v6_dispatch_chains,
                v6_ep_manager,
                v6_fip_manager,
            ]

        monitored_items += [actor.greenlet for actor in top_level_actors]

        # Try to ensure that the nf_conntrack_netlink kernel module is present.
        # This works around an issue[1] where the first call to the "conntrack"
        # command fails while waiting for the module to load.
        # [1] https://github.com/projectcalico/calico/issues/986
        load_nf_conntrack()

        # Install the global rules before we start polling for updates.
        _log.info("Installing global rules.")
        install_global_rules(config, v4_filter_updater, v4_nat_updater, ip_version=4)
        if v6_enabled:
            install_global_rules(config, v6_filter_updater, v6_nat_updater, ip_version=6, raw_updater=v6_raw_updater)

        # Start polling for updates. These kicks make the actors poll
        # indefinitely.
        _log.info("Starting polling for interface and etcd updates.")
        f = iface_watcher.watch_interfaces(async=True)
        monitored_items.append(f)
        etcd_api.start_watch(update_splitter, async=True)

        # Register a SIG_USR handler to trigger a diags dump.
        def dump_top_level_actors(log):
            for a in top_level_actors:
                # The output will include queue length and the like.
                log.info("%s", a)

        futils.register_diags("Top-level actors", dump_top_level_actors)
        futils.register_process_statistics()
        try:
            gevent.signal(signal.SIGUSR1, functools.partial(futils.dump_diags))
        except AttributeError:
            # It doesn't matter too much if we fail to do this.
            _log.warning("Unable to install diag dump handler")
            pass

        # Wait for something to fail.
        _log.info("All top-level actors started, waiting on failures...")
        stopped_greenlets_iter = gevent.iwait(monitored_items)

        stopped_greenlet = next(stopped_greenlets_iter)
        try:
            stopped_greenlet.get()
        except Exception:
            _log.exception("Greenlet failed: %s", stopped_greenlet)
            raise
        else:
            _log.error("Greenlet %s unexpectedly returned.", stopped_greenlet)
            raise AssertionError("Greenlet unexpectedly returned")
    except:
        _log.exception("Exception killing main greenlet")
        raise
예제 #4
0
def _main_greenlet(config):
    """
    The root of our tree of greenlets.  Responsible for restarting
    its children if desired.
    """
    try:
        _log.info("Connecting to etcd to get our configuration.")
        hosts_ipset_v4 = IpsetActor(HOSTS_IPSET_V4)

        etcd_api = EtcdAPI(config, hosts_ipset_v4)
        etcd_api.start()
        # Ask the EtcdAPI to fill in the global config object before we
        # proceed.  We don't yet support config updates.
        config_loaded = etcd_api.load_config(async=False)
        config_loaded.wait()

        # Ensure the Kernel's global options are correctly configured for
        # Calico.
        devices.configure_global_kernel_config()

        _log.info("Main greenlet: Configuration loaded, starting remaining "
                  "actors...")

        monitored_items = []
        if config.PROM_METRICS_ENABLED:
            httpd = HTTPServer(("0.0.0.0", config.PROM_METRICS_PORT),
                               MetricsHandler)
            stats_server = gevent.Greenlet(httpd.serve_forever)
            stats_server.start()
            monitored_items.append(stats_server)

        v4_filter_updater = IptablesUpdater("filter", ip_version=4,
                                            config=config)
        v4_nat_updater = IptablesUpdater("nat", ip_version=4, config=config)
        v4_ipset_mgr = IpsetManager(IPV4, config)
        v4_masq_manager = MasqueradeManager(IPV4, v4_nat_updater)
        v4_rules_manager = RulesManager(config,
                                        4,
                                        v4_filter_updater,
                                        v4_ipset_mgr)
        v4_dispatch_chains = DispatchChains(config, 4, v4_filter_updater)
        v4_fip_manager = FloatingIPManager(config, 4, v4_nat_updater)
        v4_ep_manager = EndpointManager(config,
                                        IPV4,
                                        v4_filter_updater,
                                        v4_dispatch_chains,
                                        v4_rules_manager,
                                        v4_fip_manager,
                                        etcd_api.status_reporter)

        cleanup_updaters = [v4_filter_updater, v4_nat_updater]
        cleanup_ip_mgrs = [v4_ipset_mgr]
        update_splitter_args = [v4_ipset_mgr,
                                v4_rules_manager,
                                v4_ep_manager,
                                v4_masq_manager,
                                v4_nat_updater]

        v6_enabled = os.path.exists("/proc/sys/net/ipv6")
        if v6_enabled:
            v6_raw_updater = IptablesUpdater("raw", ip_version=6, config=config)
            v6_filter_updater = IptablesUpdater("filter", ip_version=6,
                                                config=config)
            v6_nat_updater = IptablesUpdater("nat", ip_version=6, config=config)
            v6_ipset_mgr = IpsetManager(IPV6, config)
            v6_rules_manager = RulesManager(config,
                                            6,
                                            v6_filter_updater,
                                            v6_ipset_mgr)
            v6_dispatch_chains = DispatchChains(config, 6, v6_filter_updater)
            v6_fip_manager = FloatingIPManager(config, 6, v6_nat_updater)
            v6_ep_manager = EndpointManager(config,
                                            IPV6,
                                            v6_filter_updater,
                                            v6_dispatch_chains,
                                            v6_rules_manager,
                                            v6_fip_manager,
                                            etcd_api.status_reporter)
            cleanup_updaters.append(v6_filter_updater)
            cleanup_ip_mgrs.append(v6_ipset_mgr)
            update_splitter_args += [v6_ipset_mgr,
                                     v6_rules_manager,
                                     v6_ep_manager,
                                     v6_raw_updater,
                                     v6_nat_updater]

        cleanup_mgr = CleanupManager(config, cleanup_updaters, cleanup_ip_mgrs)
        update_splitter_args.append(cleanup_mgr)
        update_splitter = UpdateSplitter(update_splitter_args)
        iface_watcher = InterfaceWatcher(update_splitter)

        _log.info("Starting actors.")
        hosts_ipset_v4.start()
        cleanup_mgr.start()

        v4_filter_updater.start()
        v4_nat_updater.start()
        v4_ipset_mgr.start()
        v4_masq_manager.start()
        v4_rules_manager.start()
        v4_dispatch_chains.start()
        v4_ep_manager.start()
        v4_fip_manager.start()

        if v6_enabled:
            v6_raw_updater.start()
            v6_filter_updater.start()
            v6_ipset_mgr.start()
            v6_nat_updater.start()
            v6_rules_manager.start()
            v6_dispatch_chains.start()
            v6_ep_manager.start()
            v6_fip_manager.start()

        iface_watcher.start()

        top_level_actors = [
            hosts_ipset_v4,
            cleanup_mgr,

            v4_filter_updater,
            v4_nat_updater,
            v4_ipset_mgr,
            v4_masq_manager,
            v4_rules_manager,
            v4_dispatch_chains,
            v4_ep_manager,
            v4_fip_manager,

            iface_watcher,
            etcd_api,
        ]

        if v6_enabled:
            top_level_actors += [
                v6_raw_updater,
                v6_filter_updater,
                v6_nat_updater,
                v6_ipset_mgr,
                v6_rules_manager,
                v6_dispatch_chains,
                v6_ep_manager,
                v6_fip_manager,
            ]

        monitored_items += [actor.greenlet for actor in top_level_actors]

        # Try to ensure that the nf_conntrack_netlink kernel module is present.
        # This works around an issue[1] where the first call to the "conntrack"
        # command fails while waiting for the module to load.
        # [1] https://github.com/projectcalico/calico/issues/986
        load_nf_conntrack()

        # Install the global rules before we start polling for updates.
        _log.info("Installing global rules.")
        install_global_rules(config, v4_filter_updater, v4_nat_updater,
                             ip_version=4)
        if v6_enabled:
            install_global_rules(config, v6_filter_updater, v6_nat_updater,
                                 ip_version=6, raw_updater=v6_raw_updater)

        # Start polling for updates. These kicks make the actors poll
        # indefinitely.
        _log.info("Starting polling for interface and etcd updates.")
        f = iface_watcher.watch_interfaces(async=True)
        monitored_items.append(f)
        etcd_api.start_watch(update_splitter, async=True)

        # Register a SIG_USR handler to trigger a diags dump.
        def dump_top_level_actors(log):
            for a in top_level_actors:
                # The output will include queue length and the like.
                log.info("%s", a)
        futils.register_diags("Top-level actors", dump_top_level_actors)
        futils.register_process_statistics()
        try:
            gevent.signal(signal.SIGUSR1, functools.partial(futils.dump_diags))
        except AttributeError:
            # It doesn't matter too much if we fail to do this.
            _log.warning("Unable to install diag dump handler")
            pass

        # Wait for something to fail.
        _log.info("All top-level actors started, waiting on failures...")
        stopped_greenlets_iter = gevent.iwait(monitored_items)

        stopped_greenlet = next(stopped_greenlets_iter)
        try:
            stopped_greenlet.get()
        except Exception:
            _log.exception("Greenlet failed: %s", stopped_greenlet)
            raise
        else:
            _log.error("Greenlet %s unexpectedly returned.", stopped_greenlet)
            raise AssertionError("Greenlet unexpectedly returned")
    except:
        _log.exception("Exception killing main greenlet")
        raise
예제 #5
0
파일: felix.py 프로젝트: sebgregoire/felix
def _main_greenlet():
    """
    The root of our tree of greenlets.  Responsible for restarting
    its children if desired.
    """
    try:
        _log.info("Connecting to etcd to get our configuration.")
        hosts_ipset_v4 = IpsetActor(HOSTS_IPSET_V4)

        monitored_items = []

        # The parent process sends us communication pipes as FD 3 and 4. Open
        # those as files.  Wrap the resulting files in a FileObject to make
        # them cooperate with gevent.
        pipe_from_parent = FileObject(os.fdopen(3, 'rb', -1), 'rb')
        pipe_to_parent = FileObject(os.fdopen(4, 'wb', -1), 'wb')

        config = Config()
        datastore = DatastoreAPI(config, pipe_from_parent, pipe_to_parent,
                                 hosts_ipset_v4)
        datastore.start()
        monitored_items.append(datastore.greenlet)

        # Ask the DatastoreAPI to fill in the global config object before we
        # proceed.  We don't yet support config updates.
        config_loaded = datastore.load_config(async=False)
        config_loaded.wait()

        # Ensure the Kernel's global options are correctly configured for
        # Calico.
        devices.configure_global_kernel_config(config)

        # Check the commands we require are present.
        futils.check_command_deps()

        _log.info("Main greenlet: Configuration loaded, starting remaining "
                  "actors...")

        if config.PROM_METRICS_ENABLED:
            httpd = HTTPServer(("0.0.0.0", config.PROM_METRICS_DRIVER_PORT),
                               MetricsHandler)
            stats_server = gevent.Greenlet(httpd.serve_forever)
            stats_server.start()
            monitored_items.append(stats_server)

        v4_filter_updater = IptablesUpdater("filter",
                                            ip_version=4,
                                            config=config)
        v4_nat_updater = IptablesUpdater("nat", ip_version=4, config=config)
        v4_ipset_mgr = IpsetManager(IPV4, config)
        v4_masq_manager = MasqueradeManager(IPV4, v4_nat_updater)
        v4_rules_manager = RulesManager(config, 4, v4_filter_updater,
                                        v4_ipset_mgr)
        v4_ep_dispatch_chains = WorkloadDispatchChains(config, 4,
                                                       v4_filter_updater)
        v4_if_dispatch_chains = HostEndpointDispatchChains(
            config, 4, v4_filter_updater)
        v4_fip_manager = FloatingIPManager(config, 4, v4_nat_updater)
        v4_ep_manager = EndpointManager(config, IPV4, v4_filter_updater,
                                        v4_ep_dispatch_chains,
                                        v4_if_dispatch_chains,
                                        v4_rules_manager, v4_fip_manager,
                                        datastore.write_api)

        cleanup_updaters = [v4_filter_updater, v4_nat_updater]
        cleanup_ip_mgrs = [v4_ipset_mgr]
        managers = [
            v4_ipset_mgr, v4_rules_manager, v4_ep_manager, v4_masq_manager,
            v4_nat_updater
        ]

        actors_to_start = [
            hosts_ipset_v4,
            v4_filter_updater,
            v4_nat_updater,
            v4_ipset_mgr,
            v4_masq_manager,
            v4_rules_manager,
            v4_ep_dispatch_chains,
            v4_if_dispatch_chains,
            v4_ep_manager,
            v4_fip_manager,
        ]

        # Determine if ipv6 is enabled using the config option.
        if config.IPV6_SUPPORT == "true":
            v6_enabled = True
            ipv6_reason = None
        elif config.IPV6_SUPPORT == "auto":
            v6_enabled, ipv6_reason = futils.detect_ipv6_supported()
        else:
            v6_enabled = False
            ipv6_reason = "Ipv6Support is 'false'"

        if v6_enabled:
            v6_raw_updater = IptablesUpdater("raw",
                                             ip_version=6,
                                             config=config)
            v6_filter_updater = IptablesUpdater("filter",
                                                ip_version=6,
                                                config=config)
            v6_nat_updater = IptablesUpdater("nat",
                                             ip_version=6,
                                             config=config)
            v6_ipset_mgr = IpsetManager(IPV6, config)
            v6_rules_manager = RulesManager(config, 6, v6_filter_updater,
                                            v6_ipset_mgr)
            v6_ep_dispatch_chains = WorkloadDispatchChains(
                config, 6, v6_filter_updater)
            v6_if_dispatch_chains = HostEndpointDispatchChains(
                config, 6, v6_filter_updater)
            v6_fip_manager = FloatingIPManager(config, 6, v6_nat_updater)
            v6_ep_manager = EndpointManager(config, IPV6, v6_filter_updater,
                                            v6_ep_dispatch_chains,
                                            v6_if_dispatch_chains,
                                            v6_rules_manager, v6_fip_manager,
                                            datastore.write_api)
            cleanup_updaters.append(v6_filter_updater)
            cleanup_ip_mgrs.append(v6_ipset_mgr)
            managers += [
                v6_ipset_mgr, v6_rules_manager, v6_ep_manager, v6_raw_updater,
                v6_nat_updater
            ]
            actors_to_start += [
                v6_raw_updater,
                v6_filter_updater,
                v6_nat_updater,
                v6_ipset_mgr,
                v6_rules_manager,
                v6_ep_dispatch_chains,
                v6_if_dispatch_chains,
                v6_ep_manager,
                v6_fip_manager,
            ]
        else:
            # Keep the linter happy.
            _log.warn("IPv6 support disabled: %s.", ipv6_reason)
            v6_filter_updater = None
            v6_nat_updater = None
            v6_raw_updater = None
            v6_if_dispatch_chains = None

        cleanup_mgr = CleanupManager(config, cleanup_updaters, cleanup_ip_mgrs)
        managers.append(cleanup_mgr)
        update_splitter = UpdateSplitter(managers)
        iface_watcher = InterfaceWatcher(update_splitter)
        actors_to_start += [
            cleanup_mgr,
            iface_watcher,
        ]

        _log.info("Starting actors.")
        for actor in actors_to_start:
            actor.start()

        monitored_items += [actor.greenlet for actor in actors_to_start]

        # Try to ensure that the nf_conntrack_netlink kernel module is present.
        # This works around an issue[1] where the first call to the "conntrack"
        # command fails while waiting for the module to load.
        # [1] https://github.com/projectcalico/felix/issues/986
        load_nf_conntrack()

        # Install the global rules before we start polling for updates.
        _log.info("Installing global rules.")
        # Dispatch chain needs to make its configuration before we insert the
        # top-level chains.
        v4_if_dispatch_chains.configure_iptables(async=False)
        install_global_rules(config,
                             v4_filter_updater,
                             v4_nat_updater,
                             ip_version=4)
        if v6_enabled:
            # Dispatch chain needs to make its configuration before we insert
            # the top-level chains.
            v6_if_dispatch_chains.configure_iptables(async=False)
            install_global_rules(config,
                                 v6_filter_updater,
                                 v6_nat_updater,
                                 ip_version=6,
                                 raw_updater=v6_raw_updater)

        # Start polling for updates. These kicks make the actors poll
        # indefinitely.
        _log.info("Starting polling for interface and etcd updates.")
        f = iface_watcher.watch_interfaces(async=True)
        monitored_items.append(f)
        datastore.start_watch(update_splitter, async=True)

        # Register a SIG_USR handler to trigger a diags dump.
        def dump_top_level_actors(log):
            for a in actors_to_start:
                # The output will include queue length and the like.
                log.info("%s", a)

        futils.register_diags("Top-level actors", dump_top_level_actors)
        futils.register_process_statistics()
        try:
            gevent.signal(signal.SIGUSR1, functools.partial(futils.dump_diags))
        except AttributeError:
            # It doesn't matter too much if we fail to do this.
            _log.warning("Unable to install diag dump handler")
            pass
        gevent.signal(signal.SIGTERM, functools.partial(shut_down, datastore))
        gevent.signal(signal.SIGINT, functools.partial(shut_down, datastore))

        # Wait for something to fail.
        _log.info("All top-level actors started, waiting on failures...")
        stopped_greenlets_iter = gevent.iwait(monitored_items)

        stopped_greenlet = next(stopped_greenlets_iter)
        try:
            stopped_greenlet.get()
        except Exception:
            _log.exception("Greenlet failed: %s", stopped_greenlet)
            raise
        else:
            _log.error("Greenlet %s unexpectedly returned.", stopped_greenlet)
            raise AssertionError("Greenlet unexpectedly returned")
    except:
        _log.exception("Exception killing main greenlet")
        raise