[AKS] az aks upgrade: Support tier switch with AKS upgrade

src/azure-cli/azure/cli/command_modules/acs/_help.py

@@ -1888,6 +1888,12 @@
     type: string
     short-summary: Until when the cluster upgradeSettings overrides are effective.
     long-summary: It needs to be in a valid date-time format that's within the next 30 days. For example, 2023-04-01T13:00:00Z. Note that if --force-upgrade is set to true and --upgrade-override-until is not set, by default it will be set to 3 days from now.
+  - name: --k8s-support-plan
+    type: string
+    short-summary: Choose from "KubernetesOfficial" or "AKSLongTermSupport", with "AKSLongTermSupport" you get 1 extra year of CVE patchs.
+  - name: --tier
+    type: string
+    short-summary: Specify SKU tier for managed clusters. '--tier standard' enables a standard managed cluster service with a financially backed SLA. '--tier free' does not have a financially backed SLA. '--tier premium' is required for '--k8s-support-plan AKSLongTermSupport'.
 
 examples:
   - name: Upgrade a managed Kubernetes cluster to a newer version. (autogenerated)

src/azure-cli/azure/cli/command_modules/acs/_params.py

@@ -672,6 +672,8 @@ def load_arguments(self, _):
         c.argument('enable_force_upgrade', action='store_true')
         c.argument('disable_force_upgrade', action='store_true', validator=validate_force_upgrade_disable_and_enable_parameters)
         c.argument('upgrade_override_until')
+        c.argument("k8s_support_plan", arg_type=get_enum_type(k8s_support_plans))
+        c.argument("tier", arg_type=get_enum_type(sku_tiers), validator=validate_sku_tier)
 
     with self.argument_context('aks scale', resource_type=ResourceType.MGMT_CONTAINERSERVICE, operation_group='managed_clusters') as c:
         c.argument('nodepool_name', validator=validate_nodepool_name, help='Node pool name, up to 12 alphanumeric characters.')

src/azure-cli/azure/cli/command_modules/acs/custom.py

@@ -66,6 +66,7 @@
     CONST_AZURE_SERVICE_MESH_UPGRADE_COMMAND_COMPLETE,
     CONST_AZURE_SERVICE_MESH_UPGRADE_COMMAND_ROLLBACK,
     CONST_AZURE_SERVICE_MESH_MODE_ISTIO,
+    CONST_MANAGED_CLUSTER_SKU_TIER_PREMIUM,
 )
 
 from azure.cli.command_modules.acs._helpers import get_snapshot_by_snapshot_id, check_is_private_link_cluster
@@ -95,6 +96,7 @@
 from azure.cli.core.profiles import ResourceType
 from azure.cli.core.util import in_cloud_console, sdk_no_wait
 from azure.core.exceptions import ResourceNotFoundError as ResourceNotFoundErrorAzCore
+from azure.mgmt.containerservice.models import KubernetesSupportPlan
 from knack.log import get_logger
 from knack.prompting import NoTTYException, prompt_y_n
 from knack.util import CLIError
@@ -824,6 +826,8 @@ def aks_upgrade(cmd,
                 enable_force_upgrade=False,
                 disable_force_upgrade=False,
                 upgrade_override_until=None,
+                tier=None,
+                k8s_support_plan=None,
                 yes=False):
     msg = 'Kubernetes may be unavailable during cluster upgrades.\n Are you sure you want to perform this operation?'
     if not yes and not prompt_y_n(msg, default="n"):
@@ -859,6 +863,15 @@ def aks_upgrade(cmd,
         mc = client.get(resource_group_name, name)
         return _remove_nulls([mc])[0]
 
+    if tier is not None:
+        instance.sku.tier = tier
+
+    if k8s_support_plan is not None:
+        instance.support_plan = k8s_support_plan
+
+    if (instance.support_plan == KubernetesSupportPlan.AKS_LONG_TERM_SUPPORT and instance.tier is not None and instance.tier.lower() != CONST_MANAGED_CLUSTER_SKU_TIER_PREMIUM.lower()):
+        raise CLIError("AKS Long Term Support is only available for Premium tier clusters.")
+
     instance = _update_upgrade_settings(
         cmd,
         instance,