3.2 Live Migration without shared storage
Windows Server 2012 also allows you to live migrate VMs between
stand-alone Hyper-V hosts without the use of any shared storage. This
scenario is also known as Live Migration Without Infrastructure (or Shared
Nothing Live Migration), and the only requirements are that the two
hosts must belong to the same Active Directory domain and that they
must be using processors from the same manufacturer (all AMD or all
Intel, for instance). When Live Migration without infrastructure is
performed, the entire VM is moved from the first host to the second
with no perceived downtime. The process basically works like this (see Figure 7):
-
The Virtual Machine Management Service (VMMS; Vmms.exe) on the first
host (where the VM originally resides) negotiates and establishes a
Live Migration connection with the VMMS on the second host.
-
A storage migration is performed, which creates a mirror on the second host of the VM’s VHD file on the first host.
-
The VM state information is migrated from the first host to the second host.
-
The original VHD file on the first host is then deleted and the Live Migration connection between the hosts is terminated.
3.3 Performing Live Migration
Live Migration can be performed from the GUI or using PowerShell,
but first you need to enable Live Migration functionality on your host
machines. This can be done by using the Hyper-V console to open the
Hyper-V Settings, as shown in Figure 8.
The tools that you can use to perform a Live Migration depend on the kind of Live Migration you want to perform. Table 3
summarizes the different methods for performing Live Migrations in
failover clustering environments, Live Migrations using SMB 3 shares,
and Live Migrations without infrastructure.
Table 3. Methods for performing different types of Live Migrations
Type of Live Migration |
GUI tools |
PowerShell cmdlets |
---|
VM is on a cluster node and managed by the cluster. |
Failover Cluster Manager |
Move-ClusterVirtualMachineRole Move-VM |
VM is on an SMB 3 share. |
Hyper-V Manager |
Move-VM |
VM is on a stand-alone host. |
Hyper-V Manager |
Move-VM |
Windows Server 2012 gives you great flexibility in how you perform Live Migrations of running VMs, including moving
different VM components to different locations on the destination host
when performing Live Migrations with or without shared storage. To see
this, right-click a running VM in Hyper-V Manager and select Move to
start the wizard for moving VMs. The first choice you make is whether
to move the VM (and, optionally, its storage) to a different host or to
move only the VM’s storage, as shown here:
Moving the storage of a running VM is called storage migration and is a new capability for Hyper-V in Windows Server 2012. Once you’ve specified the name of
the host you want to move the VM to, you’re presented with three
options:
-
Moving all the VM’s files to a single location
-
Moving different files of the VM to different locations
-
Moving all the VM’s files except its VHDs
In each case, the target locations could be a shared folder on a
Windows Server 2012 file server or a local directory on the destination
host:
If you choose the second option of moving
different files of the VM to different locations as shown here, you’re
presented with additional options for specifying how to move the storage:
Choosing to move the VM’s items to different locations lets you
specify which items you want to move, including the VHDs, current
configuration, snapshot files, and smart paging files for the VM:
Additional wizard pages allow you to specify the exact way in which these items should be moved.