From baa478546d8cac98a706010699d64f8c2f70b5bf Mon Sep 17 00:00:00 2001 From: "Jason Zions (MSFT)" Date: Fri, 10 May 2019 18:38:55 +0000 Subject: 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. --- cloudinit/sources/helpers/azure.py | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) (limited to 'cloudinit/sources') diff --git a/cloudinit/sources/helpers/azure.py b/cloudinit/sources/helpers/azure.py index d3af05ee..82c4c8c4 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) -- cgit v1.2.3