From f54ebeac5b95c7481718e09c4598a86bc1a8dcfb Mon Sep 17 00:00:00 2001 From: Eduardo Otubo Date: Wed, 3 Jul 2019 13:14:53 +0200 Subject: [PATCH] Azure: Return static fallback address as if failed to find endpoint RH-Author: Eduardo Otubo Message-id: <20190703131453.15811-1-otubo@redhat.com> Patchwork-id: 89354 O-Subject: [RHEL-7.8 cloud-init PATCH] Azure: Return static fallback address as if failed to find endpoint Bugzilla: 1726701 RH-Acked-by: Bandan Das RH-Acked-by: Mohammed Gamal BZ: 1687565 BRANCH: rhel7/master-18.5 UPSTREAM: baa478546d8cac98a706010699d64f8c2f70b5bf BREW: 22476988 commit aefb0f1c281740ef307116509057770062d61375 Author: Jason Zions (MSFT) Date: Fri May 10 18:38:55 2019 +0000 Azure: Return static fallback address as if failed to find endpoint The Azure data source helper attempts to use information in the dhcp lease to find the Wireserver endpoint (IP address). Under some unusual circumstances, those attempts will fail. This change uses a static address, known to be always correct in the Azure public and sovereign clouds, when the helper fails to locate a valid dhcp lease. This address is not guaranteed to be correct in Azure Stack environments; it's still best to use the information from the lease whenever possible. Signed-off-by: Eduardo Otubo Signed-off-by: Miroslav Rezanina --- cloudinit/sources/helpers/azure.py | 14 +++++++++++--- tests/unittests/test_datasource/test_azure_helper.py | 9 +++++++-- 2 files changed, 18 insertions(+), 5 deletions(-) diff --git a/cloudinit/sources/helpers/azure.py b/cloudinit/sources/helpers/azure.py index d3af05e..82c4c8c 100755 --- a/cloudinit/sources/helpers/azure.py +++ b/cloudinit/sources/helpers/azure.py @@ -20,6 +20,9 @@ from cloudinit.reporting import events LOG = logging.getLogger(__name__) +# This endpoint matches the format as found in dhcp lease files, since this +# value is applied if the endpoint can't be found within a lease file +DEFAULT_WIRESERVER_ENDPOINT = "a8:3f:81:10" azure_ds_reporter = events.ReportEventStack( name="azure-ds", @@ -297,7 +300,12 @@ class WALinuxAgentShim(object): @azure_ds_telemetry_reporter def _get_value_from_leases_file(fallback_lease_file): leases = [] - content = util.load_file(fallback_lease_file) + try: + content = util.load_file(fallback_lease_file) + except IOError as ex: + LOG.error("Failed to read %s: %s", fallback_lease_file, ex) + return None + LOG.debug("content is %s", content) option_name = _get_dhcp_endpoint_option_name() for line in content.splitlines(): @@ -372,9 +380,9 @@ class WALinuxAgentShim(object): fallback_lease_file) value = WALinuxAgentShim._get_value_from_leases_file( fallback_lease_file) - if value is None: - raise ValueError('No endpoint found.') + LOG.warning("No lease found; using default endpoint") + value = DEFAULT_WIRESERVER_ENDPOINT endpoint_ip_address = WALinuxAgentShim.get_ip_from_lease_value(value) LOG.debug('Azure endpoint found at %s', endpoint_ip_address) diff --git a/tests/unittests/test_datasource/test_azure_helper.py b/tests/unittests/test_datasource/test_azure_helper.py index 0255616..bd006ab 100644 --- a/tests/unittests/test_datasource/test_azure_helper.py +++ b/tests/unittests/test_datasource/test_azure_helper.py @@ -67,12 +67,17 @@ class TestFindEndpoint(CiTestCase): self.networkd_leases.return_value = None def test_missing_file(self): - self.assertRaises(ValueError, wa_shim.find_endpoint) + """wa_shim find_endpoint uses default endpoint if leasefile not found + """ + self.assertEqual(wa_shim.find_endpoint(), "168.63.129.16") def test_missing_special_azure_line(self): + """wa_shim find_endpoint uses default endpoint if leasefile is found + but does not contain DHCP Option 245 (whose value is the endpoint) + """ self.load_file.return_value = '' self.dhcp_options.return_value = {'eth0': {'key': 'value'}} - self.assertRaises(ValueError, wa_shim.find_endpoint) + self.assertEqual(wa_shim.find_endpoint(), "168.63.129.16") @staticmethod def _build_lease_content(encoded_address): -- 1.8.3.1