Azure: eject the provisioning iso before reporting ready (#861)

Due to hyper-v implementations, iso ejection is more efficient if performed
from within the guest. The code will attempt to perform a best-effort ejection.
Failure during ejection will not prevent reporting ready from happening. If iso
ejection is successful, later iso ejection from the platform will be a no-op.
In the event the iso ejection from the guest fails, iso ejection will still happen at
the platform level.

1 files changed, 19 insertions, 3 deletions

diff --git a/cloudinit/sources/DataSourceAzure.py b/cloudinit/sources/DataSourceAzure.py
index 8c7fb021..eac6405a 100755
--- a/cloudinit/sources/DataSourceAzure.py
+++ b/cloudinit/sources/DataSourceAzure.py
@@ -332,6 +332,7 @@ class DataSourceAzure(sources.DataSource):
     dsname = 'Azure'
     _negotiated = False
     _metadata_imds = sources.UNSET
+    _ci_pkl_version = 1
 
     def __init__(self, sys_cfg, distro, paths):
         sources.DataSource.__init__(self, sys_cfg, distro, paths)
@@ -346,8 +347,13 @@ class DataSourceAzure(sources.DataSource):
         # Regenerate network config new_instance boot and every boot
         self.update_events['network'].add(EventType.BOOT)
         self._ephemeral_dhcp_ctx = None
-
         self.failed_desired_api_version = False
+        self.iso_dev = None
+
+    def _unpickle(self, ci_pkl_version: int) -> None:
+        super()._unpickle(ci_pkl_version)
+        if "iso_dev" not in self.__dict__:
+            self.iso_dev = None
 
     def __str__(self):
         root = sources.DataSource.__str__(self)
@@ -459,6 +465,13 @@ class DataSourceAzure(sources.DataSource):
                     '%s was not mountable' % cdev, logger_func=LOG.warning)
                 continue
 
+            report_diagnostic_event("Found provisioning metadata in %s" % cdev,
+                                    logger_func=LOG.debug)
+
+            # save the iso device for ejection before reporting ready
+            if cdev.startswith("/dev"):
+                self.iso_dev = cdev
+
             perform_reprovision = reprovision or self._should_reprovision(ret)
             perform_reprovision_after_nic_attach = (
                 reprovision_after_nic_attach or
@@ -1226,7 +1239,9 @@ class DataSourceAzure(sources.DataSource):
         @return: The success status of sending the ready signal.
         """
         try:
-            get_metadata_from_fabric(None, lease['unknown-245'])
+            get_metadata_from_fabric(fallback_lease_file=None,
+                                     dhcp_opts=lease['unknown-245'],
+                                     iso_dev=self.iso_dev)
             return True
         except Exception as e:
             report_diagnostic_event(
@@ -1332,7 +1347,8 @@ class DataSourceAzure(sources.DataSource):
         metadata_func = partial(get_metadata_from_fabric,
                                 fallback_lease_file=self.
                                 dhclient_lease_file,
-                                pubkey_info=pubkey_info)
+                                pubkey_info=pubkey_info,
+                                iso_dev=self.iso_dev)
 
         LOG.debug("negotiating with fabric via agent command %s",
                   self.ds_cfg['agent_command'])