Added Limitations section to Extensions (#547)

Author: abh1sar

source/adminguide/extensions.rst

@@ -92,6 +92,8 @@ CloudStack provides sample built-in orchestrator extensions for demonstration an
 
 .. include:: extensions/builtin_extensions.rst
 
+.. include:: extensions/limitations.rst
+
 .. include:: extensions/troubleshooting.rst
 
 .. include:: extensions/developer.rst

source/adminguide/extensions/builtin_extensions.rst

@@ -188,6 +188,7 @@ Adding Hyper-V to CloudStack
 #. **Add Host.** Add a host to the newly created cluster with the following details:
 
    |hyperv-add-host.png|
+    **Note**: Add the detail **verify_tls_certificate** set to **false** to skip TLS certificate verification for self-signed certificates.
 
 #. **Create Template.** A Template in CloudStack can map to either a `Template` or an `ISO` in Hyper-V.
    Provide a dummy `url` and template name. Select `External` as the hypervisor and `HyperV` as the extension. Under `External Details`, specify:

source/adminguide/extensions/limitations.rst

@@ -0,0 +1,55 @@
+.. Licensed to the Apache Software Foundation (ASF) under one
+   or more contributor license agreements.  See the NOTICE file
+   distributed with this work for additional information#
+   regarding copyright ownership.  The ASF licenses this file
+   to you under the Apache License, Version 2.0 (the
+   "License"); you may not use this file except in compliance
+   with the License.  You may obtain a copy of the License at
+   http://www.apache.org/licenses/LICENSE-2.0
+   Unless required by applicable law or agreed to in writing,
+   software distributed under the License is distributed on an
+   "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+   KIND, either express or implied.  See the License for the
+   specific language governing permissions and limitations
+   under the License.
+   
+
+Limitations
+===========
+
+Although the external Instances behave a lot like CloudStack managed
+Instances in many ways, there are some limitations. Some of these
+limitations are due to the framework itself, while others can be addressed
+by adding custom actions in the scripts written for the built-in extensions.
+
+**Some general features/actions not supported at the framework level:**
+
+   - Console access to the external Instances.
+
+   - Data volumes.
+
+   - User Data and Metadata services.
+
+   - SSH key injection.
+
+   - Affinity Groups.
+
+   - Migrate Instance.
+
+   - Host Capacity and Utilization Stats.
+
+   - Add Nics to Instance post deployment.
+
+**Actions which can be implemented using Custom Actions in built-in extensions:**
+
+   - Reinstall Instance.
+
+   - Backup and Restore.
+
+   - Recurring Snapshots.
+
+   - Change Service Offering.
+
+   - Resize Volume.
+
+   - Attach ISO.