Documentation related to Persistent domainXML

Author: sudo87

source/adminguide/virtual_machines/importing_unmanaging_vms.rst

@@ -362,6 +362,22 @@ Preserving unmanaged Instance NICs
 The zone setting: unmanage.vm.preserve.nics can be used to preserve Instance NICs and its MAC addresses after unmanaging them. If set to true, the Instance NICs (and their MAC addresses) are preserved when unmanaging it. Otherwise, NICs are removed and MAC addresses can be reassigned.
 
 
+KVM Specific: Persistent Domain XML when unmanaging Instances
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Since 4.22, domain XML will be made persistent when Instance is unmanaged from CloudStack. This will allow to manage the Instance outside of CloudStack using virsh or other libvirt tools. The domain XML will be stored in directory /etc/libvirt/qemu.
+
+Domain XML is taken from Instance but varies based on their state:
+
+- Running Instance
+   - Domain XML is contructed from the Instance and persisted on the Host where the Instance is running
+- Stopped Instance
+   - Domain XML is constructed from the Instance details available in CloudStack database
+   - Domain XML will pe persisted on the last host where the Instance was running before stopping it
+
+.. note:: We recommend Unmanaging Instance in Running state to preserve the exact domain XML. There is potential to loose some information when unmanaging in Stopped state.
+
+
 Unmanaging Instance actions
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~