diff --git a/src/aks-preview/azext_aks_preview/_client_factory.py b/src/aks-preview/azext_aks_preview/_client_factory.py
index 39f78303524..175a03b2d95 100644
--- a/src/aks-preview/azext_aks_preview/_client_factory.py
+++ b/src/aks-preview/azext_aks_preview/_client_factory.py
@@ -62,6 +62,8 @@ def get_auth_management_client(cli_ctx, scope=None, **_):
         matched = re.match('/subscriptions/(?P<subscription>[^/]*)/', scope)
         if matched:
             subscription_id = matched.groupdict()['subscription']
+        else:
+            raise CLIError("{} does not contain subscription Id.".format(scope))
     return get_mgmt_service_client(cli_ctx, ResourceType.MGMT_AUTHORIZATION, subscription_id=subscription_id)
 
 
diff --git a/src/aks-preview/azext_aks_preview/_params.py b/src/aks-preview/azext_aks_preview/_params.py
index 2efb02818a3..27c3d71e92a 100644
--- a/src/aks-preview/azext_aks_preview/_params.py
+++ b/src/aks-preview/azext_aks_preview/_params.py
@@ -21,7 +21,8 @@
     validate_nodepool_name, validate_vm_set_type, validate_load_balancer_sku,
     validate_load_balancer_outbound_ips, validate_load_balancer_outbound_ip_prefixes,
     validate_taints, validate_priority, validate_eviction_policy, validate_spot_max_price, validate_acr, validate_user,
-    validate_load_balancer_outbound_ports, validate_load_balancer_idle_timeout, validate_nodepool_tags, validate_nodepool_labels)
+    validate_load_balancer_outbound_ports, validate_load_balancer_idle_timeout, validate_nodepool_tags,
+    validate_nodepool_labels, validate_vnet_subnet_id)
 from ._consts import CONST_OUTBOUND_TYPE_LOAD_BALANCER, \
     CONST_OUTBOUND_TYPE_USER_DEFINED_ROUTING, CONST_SCALE_SET_PRIORITY_REGULAR, CONST_SCALE_SET_PRIORITY_SPOT, \
     CONST_SPOT_EVICTION_POLICY_DELETE, CONST_SPOT_EVICTION_POLICY_DEALLOCATE
@@ -80,7 +81,7 @@ def load_arguments(self, _):
         c.argument('no_ssh_key', options_list=['--no-ssh-key', '-x'])
         c.argument('pod_cidr')
         c.argument('service_cidr')
-        c.argument('vnet_subnet_id')
+        c.argument('vnet_subnet_id', type=str, validator=validate_vnet_subnet_id)
         c.argument('workspace_resource_id')
         c.argument('skip_subnet_role_assignment', action='store_true')
         c.argument('enable_cluster_autoscaler', action='store_true')
diff --git a/src/aks-preview/azext_aks_preview/_validators.py b/src/aks-preview/azext_aks_preview/_validators.py
index 8776a9925e0..b8bd09757ba 100644
--- a/src/aks-preview/azext_aks_preview/_validators.py
+++ b/src/aks-preview/azext_aks_preview/_validators.py
@@ -239,6 +239,15 @@ def validate_user(namespace):
         raise CLIError("--user can only be clusterUser or clusterMonitoringUser")
 
 
+def validate_vnet_subnet_id(namespace):
+    if namespace.vnet_subnet_id is not None:
+        if namespace.vnet_subnet_id == '':
+            return
+        from msrestazure.tools import is_valid_resource_id
+        if not is_valid_resource_id(namespace.vnet_subnet_id):
+            raise CLIError("--vnet-subnet-id is not a valid Azure resource ID.")
+
+
 def validate_load_balancer_outbound_ports(namespace):
     """validate load balancer profile outbound allocated ports"""
     if namespace.load_balancer_outbound_ports is not None:
diff --git a/src/aks-preview/azext_aks_preview/custom.py b/src/aks-preview/azext_aks_preview/custom.py
index c4e2479e04a..89dc684edf8 100644
--- a/src/aks-preview/azext_aks_preview/custom.py
+++ b/src/aks-preview/azext_aks_preview/custom.py
@@ -1465,9 +1465,8 @@ def aks_kollect(cmd,    # pylint: disable=too-many-statements,too-many-locals
     if not prompt_y_n('Do you want to see analysis results now?', default="n"):
         print(f"You can run 'az aks kanalyze -g {resource_group_name} -n {name}' "
               f"anytime to check the analysis results.")
-        return
-
-    display_diagnostics_report(temp_kubeconfig_path)
+    else:
+        display_diagnostics_report(temp_kubeconfig_path)
 
     return
 
diff --git a/src/aks-preview/azext_aks_preview/tests/latest/test_validators.py b/src/aks-preview/azext_aks_preview/tests/latest/test_validators.py
index 6d5004a1647..4757c4f8810 100644
--- a/src/aks-preview/azext_aks_preview/tests/latest/test_validators.py
+++ b/src/aks-preview/azext_aks_preview/tests/latest/test_validators.py
@@ -115,3 +115,34 @@ class Namespace:
     def __init__(self, api_server_authorized_ip_ranges=None, cluster_autoscaler_profile=None):
         self.api_server_authorized_ip_ranges = api_server_authorized_ip_ranges
         self.cluster_autoscaler_profile = cluster_autoscaler_profile
+
+
+class TestVNetSubnetId(unittest.TestCase):
+    def test_invalid_vnet_subnet_id(self):
+        invalid_vnet_subnet_id = "dummy subnet id"
+        namespace = VnetSubnetIdNamespace(invalid_vnet_subnet_id)
+        err = ("--vnet-subnet-id is not a valid Azure resource ID.")
+
+        with self.assertRaises(CLIError) as cm:
+            validators.validate_vnet_subnet_id(namespace)
+        self.assertEqual(str(cm.exception), err)
+
+    def test_valid_vnet_subnet_id(self):
+        invalid_vnet_subnet_id = "/subscriptions/testid/resourceGroups/MockedResourceGroup/providers/Microsoft.Network/virtualNetworks/MockedNetworkId/subnets/MockedSubNetId"
+        namespace = VnetSubnetIdNamespace(invalid_vnet_subnet_id)
+        validators.validate_vnet_subnet_id(namespace)
+
+    def test_none_vnet_subnet_id(self):
+        invalid_vnet_subnet_id = None
+        namespace = VnetSubnetIdNamespace(invalid_vnet_subnet_id)
+        validators.validate_vnet_subnet_id(namespace)
+
+    def test_empty_vnet_subnet_id(self):
+        invalid_vnet_subnet_id = ""
+        namespace = VnetSubnetIdNamespace(invalid_vnet_subnet_id)
+        validators.validate_vnet_subnet_id(namespace)
+
+
+class VnetSubnetIdNamespace:
+    def __init__(self, vnet_subnet_id):
+        self.vnet_subnet_id = vnet_subnet_id