Implementation of new conf flag AutoUpdate.UpdateToLatestVersion support

azurelinuxagent/common/agent_supported_feature.py

@@ -76,15 +76,15 @@ def __init__(self):
 
 class _GAVersioningGovernanceFeature(AgentSupportedFeature):
     """
-    CRP would drive the RSM upgrade version if agent reports that it does support RSM upgrades with this flag otherwise CRP fallback to largest version.
+    CRP would drive the RSM update if agent reports that it does support RSM upgrades with this flag otherwise CRP fallback to largest version.
     Agent doesn't report supported feature flag if auto update is disabled or old version of agent running that doesn't understand GA versioning.
 
     Note: Especially Windows need this flag to report to CRP that GA doesn't support the updates. So linux adopted same flag to have a common solution.
     """
 
     __NAME = SupportedFeatureNames.GAVersioningGovernance
     __VERSION = "1.0"
-    __SUPPORTED = conf.get_autoupdate_enabled()
+    __SUPPORTED = conf.get_auto_update_to_latest_version()
 
     def __init__(self):
         super(_GAVersioningGovernanceFeature, self).__init__(name=self.__NAME,

azurelinuxagent/common/conf.py

@@ -128,6 +128,7 @@ def load_conf_from_file(conf_file_path, conf=__conf__):
     "ResourceDisk.EnableSwap": False,
     "ResourceDisk.EnableSwapEncryption": False,
     "AutoUpdate.Enabled": True,
+    "AutoUpdate.UpdateToLatestVersion": True,
     "EnableOverProvisioning": True,
     #
     # "Debug" options are experimental and may be removed in later
@@ -136,7 +137,6 @@ def load_conf_from_file(conf_file_path, conf=__conf__):
     "Debug.CgroupLogMetrics": False,
     "Debug.CgroupDisableOnProcessCheckFailure": True,
     "Debug.CgroupDisableOnQuotaCheckFailure": True,
-    "Debug.DownloadNewAgents": True,
     "Debug.EnableAgentMemoryUsageCheck": False,
     "Debug.EnableFastTrack": True,
     "Debug.EnableGAVersioning": True
@@ -475,8 +475,8 @@ def get_autoupdate_gafamily(conf=__conf__):
     return conf.get("AutoUpdate.GAFamily", "Prod")
 
 
-def get_autoupdate_enabled(conf=__conf__):
-    return conf.get_switch("AutoUpdate.Enabled", True)
+def get_autoupdate_enabled(conf=__conf__, default=True):
+    return conf.get_switch("AutoUpdate.Enabled", default)
 
 
 def get_autoupdate_frequency(conf=__conf__):
@@ -503,15 +503,19 @@ def get_monitor_network_configuration_changes(conf=__conf__):
     return conf.get_switch("Monitor.NetworkConfigurationChanges", False)
 
 
-def get_download_new_agents(conf=__conf__):
+def get_auto_update_to_latest_version(conf=__conf__):
     """
-    If True, the agent go through update logic to look for new agents to download otherwise it will stop agent updates.
-    NOTE: AutoUpdate.Enabled controls whether the Agent downloads new update and also whether any downloaded updates are started or not, while DownloadNewAgents controls only the former.
-    AutoUpdate.Enabled == false -> Agent preinstalled on the image will process extensions and will not update (regardless of DownloadNewAgents flag)
-    AutoUpdate.Enabled == true and DownloadNewAgents == true, any update already downloaded will be started, and agent look for future updates
-    AutoUpdate.Enabled == true and DownloadNewAgents == false, any update already downloaded will be started, but the agent will not look for future updates
+    If set to True, agent will update to the latest version
+    NOTE:
+        when both turned on, both AutoUpdate.Enabled and AutoUpdate.UpdateToLatestVersion same meaning: update to latest version
+        when turned off, AutoUpdate.Enabled: reverts to pre-installed agent, AutoUpdate.UpdateToLatestVersion: uses latest version already installed on the vm and does not download new agents
+        Even we are deprecating AutoUpdate.Enabled, we still need to support if users explicitly setting it instead new flag.
+        If AutoUpdate.UpdateToLatestVersion is present, it overrides any value set for AutoUpdate.Enabled (if present).
+        If AutoUpdate.Enabled is present and set to 'n', we adhere to AutoUpdate.Enabled flag's behavior
+        if both not present, we default to True.
     """
-    return conf.get_switch("Debug.DownloadNewAgents", True)
+    default = get_autoupdate_enabled()
+    return conf.get_switch("AutoUpdate.UpdateToLatestVersion", default)
 
 
 def get_cgroup_check_period(conf=__conf__):

azurelinuxagent/ga/agent_update_handler.py

@@ -141,8 +141,8 @@ def _get_agent_family_manifest(self, goal_state):
     def run(self, goal_state, ext_gs_updated):
 
         try:
-            # Ignore new agents if update is disabled. The latter flag only used in e2e tests.
-            if not conf.get_autoupdate_enabled() or not conf.get_download_new_agents():
+            # If auto update is disabled, we don't proceed with update
+            if not conf.get_auto_update_to_latest_version():
                 return
 
             # Update the state only on new goal state

azurelinuxagent/ga/update.py

@@ -752,6 +752,12 @@ def log_if_agent_versioning_feature_disabled():
             log_if_op_disabled("OS.EnableFirewall", conf.enable_firewall())
             log_if_op_disabled("Extensions.Enabled", conf.get_extensions_enabled())
             log_if_op_disabled("AutoUpdate.Enabled", conf.get_autoupdate_enabled())
+            log_if_op_disabled("AutoUpdate.UpdateToLatestVersion", conf.get_auto_update_to_latest_version())
+
+            if conf.get_autoupdate_enabled(default=None) is not None and conf.get_autoupdate_enabled() != conf.get_auto_update_to_latest_version():
+                msg = "AutoUpdate.Enabled property is **Deprecated** now but it's set to different value from AutoUpdate.UpdateToLatestVersion. Please consider removing it if added by mistake"
+                logger.warn(msg)
+                add_event(AGENT_NAME, op=WALAEventOperation.ConfigurationChange, message=msg)
 
             if conf.enable_firewall():
                 log_if_int_changed_from_default("OS.EnableFirewallPeriod", conf.get_enable_firewall_period())

config/alpine/waagent.conf

@@ -75,7 +75,11 @@ OS.OpensslPath=None
 OS.SshDir=/etc/ssh
 
 # Enable or disable goal state processing auto-update, default is enabled
-# AutoUpdate.Enabled=y
+# When turned off, it remains on latest version installed on the vm
+# Added this new option AutoUpdate.UpdateToLatestVersion in place of AutoUpdate.Enabled, and encourage users to transition to this new option
+# See wiki[https://github.com/Azure/WALinuxAgent/wiki/FAQ#autoupdateenabled-vs-autoupdateupdatetolatestversion] for more details
+# TODO: Update the wiki link and point to readme page or public facing doc
+# AutoUpdate.UpdateToLatestVersion=y
 
 # Determine the update family, this should not be changed
 # AutoUpdate.GAFamily=Prod

config/arch/waagent.conf

@@ -100,7 +100,10 @@ OS.SshDir=/etc/ssh
 # OS.EnableRDMA=y
 
 # Enable or disable goal state processing auto-update, default is enabled
-# AutoUpdate.Enabled=y
+# When turned off, it remains on latest version installed on the vm
+# Added this new option AutoUpdate.UpdateToLatestVersion in place of AutoUpdate.Enabled, and encourage users to transition to this new option
+# See wiki[https://github.com/Azure/WALinuxAgent/wiki/FAQ#autoupdateenabled-vs-autoupdateupdatetolatestversion] for more details
+# AutoUpdate.UpdateToLatestVersion=y
 
 # Determine the update family, this should not be changed
 # AutoUpdate.GAFamily=Prod

config/bigip/waagent.conf

@@ -82,7 +82,10 @@ OS.SshdConfigPath=/config/ssh/sshd_config
 OS.EnableRDMA=n
 
 # Enable or disable goal state processing auto-update, default is enabled
-AutoUpdate.Enabled=y
+# When turned off, it remains on latest version installed on the vm
+# Added this new option AutoUpdate.UpdateToLatestVersion in place of AutoUpdate.Enabled, and encourage users to transition to this new option
+# See wiki[https://github.com/Azure/WALinuxAgent/wiki/FAQ#autoupdateenabled-vs-autoupdateupdatetolatestversion] for more details
+# AutoUpdate.UpdateToLatestVersion=y
 
 # Determine the update family, this should not be changed
 # AutoUpdate.GAFamily=Prod

config/clearlinux/waagent.conf

@@ -73,8 +73,12 @@ OS.OpensslPath=None
 # Set the path to SSH keys and configuration files
 OS.SshDir=/etc/ssh
 
-# Enable or disable self-update, default is enabled
-AutoUpdate.Enabled=y
+# Enable or disable goal state processing auto-update, default is enabled
+# When turned off, it remains on latest version installed on the vm
+# Added this new option AutoUpdate.UpdateToLatestVersion in place of AutoUpdate.Enabled, and encourage users to transition to this new option
+# See wiki[https://github.com/Azure/WALinuxAgent/wiki/FAQ#autoupdateenabled-vs-autoupdateupdatetolatestversion] for more details
+# AutoUpdate.UpdateToLatestVersion=y
+
 AutoUpdate.GAFamily=Prod
 
 # Determine if the overprovisioning feature is enabled. If yes, hold extension

config/coreos/waagent.conf

@@ -104,7 +104,10 @@ OS.OpensslPath=None
 # OS.EnableRDMA=y
 
 # Enable or disable goal state processing auto-update, default is enabled
-# AutoUpdate.Enabled=y
+# When turned off, it remains on latest version installed on the vm
+# Added this new option AutoUpdate.UpdateToLatestVersion in place of AutoUpdate.Enabled, and encourage users to transition to this new option
+# See wiki[https://github.com/Azure/WALinuxAgent/wiki/FAQ#autoupdateenabled-vs-autoupdateupdatetolatestversion] for more details
+# AutoUpdate.UpdateToLatestVersion=y
 
 # Determine the update family, this should not be changed
 # AutoUpdate.GAFamily=Prod

config/debian/waagent.conf

@@ -110,7 +110,10 @@ OS.SshDir=/etc/ssh
 # OS.EnableRDMA=y
 
 # Enable or disable goal state processing auto-update, default is enabled
-# AutoUpdate.Enabled=y
+# When turned off, it remains on latest version installed on the vm
+# Added this new option AutoUpdate.UpdateToLatestVersion in place of AutoUpdate.Enabled, and encourage users to transition to this new option
+# See wiki[https://github.com/Azure/WALinuxAgent/wiki/FAQ#autoupdateenabled-vs-autoupdateupdatetolatestversion] for more details
+# AutoUpdate.UpdateToLatestVersion=y
 
 # Determine the update family, this should not be changed
 # AutoUpdate.GAFamily=Prod

config/devuan/waagent.conf

@@ -104,7 +104,10 @@ OS.SshDir=/etc/ssh
 # OS.EnableRDMA=y
 
 # Enable or disable goal state processing auto-update, default is enabled
-# AutoUpdate.Enabled=y
+# When turned off, it remains on latest version installed on the vm
+# Added this new option AutoUpdate.UpdateToLatestVersion in place of AutoUpdate.Enabled, and encourage users to transition to this new option
+# See wiki[https://github.com/Azure/WALinuxAgent/wiki/FAQ#autoupdateenabled-vs-autoupdateupdatetolatestversion] for more details
+# AutoUpdate.UpdateToLatestVersion=y
 
 # Determine the update family, this should not be changed
 # AutoUpdate.GAFamily=Prod

config/freebsd/waagent.conf

@@ -102,7 +102,10 @@ OS.SudoersDir=/usr/local/etc/sudoers.d
 # OS.EnableRDMA=y
 
 # Enable or disable goal state processing auto-update, default is enabled
-# AutoUpdate.Enabled=y
+# When turned off, it remains on latest version installed on the vm
+# Added this new option AutoUpdate.UpdateToLatestVersion in place of AutoUpdate.Enabled, and encourage users to transition to this new option
+# See wiki[https://github.com/Azure/WALinuxAgent/wiki/FAQ#autoupdateenabled-vs-autoupdateupdatetolatestversion] for more details
+# AutoUpdate.UpdateToLatestVersion=y
 
 # Determine the update family, this should not be changed
 # AutoUpdate.GAFamily=Prod

config/gaia/waagent.conf

@@ -101,8 +101,15 @@ OS.SshDir=/etc/ssh
 OS.EnableRDMA=n
 
 # Enable or disable goal state processing auto-update, default is enabled
+# When turned off, it reverts to the pre-installed agent that comes with image
+# AutoUpdate.Enabled is a legacy parameter used only for backwards compatibility. We encourage users to transition to new option AutoUpdate.UpdateToLatestVersion
+# See wiki[https://github.com/Azure/WALinuxAgent/wiki/FAQ#autoupdateenabled-vs-autoupdateupdatetolatestversion] for more details
 AutoUpdate.Enabled=n
 
+# Enable or disable goal state processing auto-update, default is enabled
+# When turned off, it remains on latest version installed on the vm
+# AutoUpdate.UpdateToLatestVersion=y
+
 # Determine the update family, this should not be changed
 # AutoUpdate.GAFamily=Prod
 

config/iosxe/waagent.conf

@@ -100,7 +100,10 @@ OS.SshDir=/etc/ssh
 # OS.EnableRDMA=y
 
 # Enable or disable goal state processing auto-update, default is enabled
-AutoUpdate.Enabled=y
+# When turned off, it remains on latest version installed on the vm
+# Added this new option AutoUpdate.UpdateToLatestVersion in place of AutoUpdate.Enabled, and encourage users to transition to this new option
+# See wiki[https://github.com/Azure/WALinuxAgent/wiki/FAQ#autoupdateenabled-vs-autoupdateupdatetolatestversion] for more details
+# AutoUpdate.UpdateToLatestVersion=y
 
 # Determine the update family, this should not be changed
 # AutoUpdate.GAFamily=Prod

config/mariner/waagent.conf

@@ -75,8 +75,12 @@ OS.OpensslPath=None
 # Set the path to SSH keys and configuration files
 OS.SshDir=/etc/ssh
 
-# Enable or disable self-update, default is enabled
-AutoUpdate.Enabled=y
+# Enable or disable goal state processing auto-update, default is enabled
+# When turned off, it remains on latest version installed on the vm
+# Added this new option AutoUpdate.UpdateToLatestVersion in place of AutoUpdate.Enabled, and encourage users to transition to this new option
+# See wiki[https://github.com/Azure/WALinuxAgent/wiki/FAQ#autoupdateenabled-vs-autoupdateupdatetolatestversion] for more details
+# AutoUpdate.UpdateToLatestVersion=y
+
 AutoUpdate.GAFamily=Prod
 
 # Determine if the overprovisioning feature is enabled. If yes, hold extension

config/nsbsd/waagent.conf

@@ -98,8 +98,15 @@ Extension.LogDir=/log/azure
 # OS.EnableRDMA=y
 
 # Enable or disable goal state processing auto-update, default is enabled
+# When turned off, it reverts to the pre-installed agent that comes with image
+# AutoUpdate.Enabled is a legacy parameter used only for backwards compatibility. We encourage users to transition to new option AutoUpdate.UpdateToLatestVersion
+# See wiki[https://github.com/Azure/WALinuxAgent/wiki/FAQ#autoupdateenabled-vs-autoupdateupdatetolatestversion] for more details
 AutoUpdate.Enabled=n
 
+# Enable or disable goal state processing auto-update, default is enabled
+# When turned off, it remains on latest version installed on the vm
+# AutoUpdate.UpdateToLatestVersion=y
+
 # Determine the update family, this should not be changed
 # AutoUpdate.GAFamily=Prod
 

config/openbsd/waagent.conf

@@ -96,7 +96,10 @@ OS.PasswordPath=/etc/master.passwd
 # OS.EnableRDMA=y
 
 # Enable or disable goal state processing auto-update, default is enabled
-# AutoUpdate.Enabled=y
+# When turned off, it remains on latest version installed on the vm
+# Added this new option AutoUpdate.UpdateToLatestVersion in place of AutoUpdate.Enabled, and encourage users to transition to this new option
+# See wiki[https://github.com/Azure/WALinuxAgent/wiki/FAQ#autoupdateenabled-vs-autoupdateupdatetolatestversion] for more details
+# AutoUpdate.UpdateToLatestVersion=y
 
 # Determine the update family, this should not be changed
 # AutoUpdate.GAFamily=Prod

config/photonos/waagent.conf

@@ -70,8 +70,12 @@ OS.OpensslPath=None
 # Set the path to SSH keys and configuration files
 OS.SshDir=/etc/ssh
 
-# Enable or disable self-update, default is enabled
-AutoUpdate.Enabled=y
+# Enable or disable goal state processing auto-update, default is enabled
+# When turned off, it remains on latest version installed on the vm
+# Added this new option AutoUpdate.UpdateToLatestVersion in place of AutoUpdate.Enabled, and encourage users to transition to this new option
+# See wiki[https://github.com/Azure/WALinuxAgent/wiki/FAQ#autoupdateenabled-vs-autoupdateupdatetolatestversion] for more details
+# AutoUpdate.UpdateToLatestVersion=y
+
 AutoUpdate.GAFamily=Prod
 
 # Determine if the overprovisioning feature is enabled. If yes, hold extension

config/suse/waagent.conf

@@ -113,7 +113,10 @@ OS.SshDir=/etc/ssh
 # OS.CheckRdmaDriver=y
 
 # Enable or disable goal state processing auto-update, default is enabled
-# AutoUpdate.Enabled=y
+# When turned off, it remains on latest version installed on the vm
+# Added this new option AutoUpdate.UpdateToLatestVersion in place of AutoUpdate.Enabled, and encourage users to transition to this new option
+# See wiki[https://github.com/Azure/WALinuxAgent/wiki/FAQ#autoupdateenabled-vs-autoupdateupdatetolatestversion] for more details
+# AutoUpdate.UpdateToLatestVersion=y
 
 # Determine the update family, this should not be changed
 # AutoUpdate.GAFamily=Prod

config/ubuntu/waagent.conf

@@ -101,7 +101,10 @@ OS.SshDir=/etc/ssh
 # OS.CheckRdmaDriver=y
 
 # Enable or disable goal state processing auto-update, default is enabled
-# AutoUpdate.Enabled=y
+# When turned off, it remains on latest version installed on the vm
+# Added this new option AutoUpdate.UpdateToLatestVersion in place of AutoUpdate.Enabled, and encourage users to transition to this new option
+# See wiki[https://github.com/Azure/WALinuxAgent/wiki/FAQ#autoupdateenabled-vs-autoupdateupdatetolatestversion] for more details
+# AutoUpdate.UpdateToLatestVersion=y
 
 # Determine the update family, this should not be changed
 # AutoUpdate.GAFamily=Prod

config/waagent.conf

@@ -122,7 +122,10 @@ OS.SshDir=/etc/ssh
 # OS.CheckRdmaDriver=y
 
 # Enable or disable goal state processing auto-update, default is enabled
-# AutoUpdate.Enabled=y
+# When turned off, it remains on latest version installed on the vm
+# Added this new option AutoUpdate.UpdateToLatestVersion in place of AutoUpdate.Enabled, and encourage users to transition to this new option
+# See wiki[https://github.com/Azure/WALinuxAgent/wiki/FAQ#autoupdateenabled-vs-autoupdateupdatetolatestversion] for more details
+# AutoUpdate.UpdateToLatestVersion=y
 
 # Determine the update family, this should not be changed
 # AutoUpdate.GAFamily=Prod

tests/common/test_conf.py

@@ -63,6 +63,7 @@ class TestConf(AgentTestCase):
         "OS.CheckRdmaDriver": False,
         "AutoUpdate.Enabled": True,
         "AutoUpdate.GAFamily": "Prod",
+        "AutoUpdate.UpdateToLatestVersion": False,
         "EnableOverProvisioning": True,
         "OS.AllowHTTP": False,
         "OS.EnableFirewall": False
@@ -144,3 +145,6 @@ def test_write_agent_disabled(self):
 
     def test_get_extensions_enabled(self):
         self.assertTrue(conf.get_extensions_enabled(self.conf))
+
+    def test_get_get_auto_update_to_latest_version(self):
+        self.assertFalse(conf.get_auto_update_to_latest_version(self.conf))

tests/data/test_waagent.conf

@@ -116,8 +116,12 @@ OS.SshDir=/notareal/path
 # OS.CheckRdmaDriver=n
 
 
+# Enable or disable goal state processing auto-update, default is enabled.
+# Deprecated now but keep it for backward compatibility
+AutoUpdate.Enabled=y
+
 # Enable or disable goal state processing auto-update, default is enabled
-# AutoUpdate.Enabled=y
+AutoUpdate.UpdateToLatestVersion=n
 
 # Determine the update family, this should not be changed
 # AutoUpdate.GAFamily=Prod

tests/ga/test_agent_update_handler.py

@@ -459,3 +459,14 @@ def test_it_should_save_rsm_state_of_the_most_recent_goal_state(self):
                 agent_update_handler.run(agent_update_handler._protocol.get_goal_state(), True)
 
             self.assertFalse(os.path.exists(state_file), "The rsm file should be removed (file: {0})".format(state_file))
+
+    def test_it_should_not_update_to_latest_if_flag_is_disabled(self):
+        self.prepare_agents(count=1)
+
+        data_file = DATA_FILE.copy()
+        data_file['ext_conf'] = "wire/ext_conf.xml"
+        with self._get_agent_update_handler(test_data=data_file) as (agent_update_handler, _):
+            with patch("azurelinuxagent.common.conf.get_auto_update_to_latest_version", return_value=False):
+                agent_update_handler.run(agent_update_handler._protocol.get_goal_state(), True)
+
+            self._assert_agent_directories_exist_and_others_dont_exist(versions=[str(CURRENT_VERSION)])

tests/test_agent.py

@@ -28,6 +28,7 @@
 EXPECTED_CONFIGURATION = \
 """AutoUpdate.Enabled = True
 AutoUpdate.GAFamily = Prod
+AutoUpdate.UpdateToLatestVersion = False
 Autoupdate.Frequency = 3600
 DVD.MountPoint = /mnt/cdrom/secure
 Debug.AgentCpuQuota = 50
@@ -41,7 +42,6 @@
 Debug.CgroupLogMetrics = False
 Debug.CgroupMonitorExpiryTime = 2022-03-31
 Debug.CgroupMonitorExtensionName = Microsoft.Azure.Monitor.AzureMonitorLinuxAgent
-Debug.DownloadNewAgents = True
 Debug.EnableAgentMemoryUsageCheck = False
 Debug.EnableFastTrack = True
 Debug.EnableGAVersioning = True