Double-Take Move Review

Like most IT professionals, I've been involved in many hardware migration projects. After reading that Double-Take Move "revolutionizes the migration process with real-time data movement" (from Double-Take Software's website), I wondered if this product could solve my migration woes.

Double-Take Move transfers data and workloads (defined as complete working systems with data) from one machine to another: either physical to physical, virtual to virtual, or any combination thereof. Think of the product as a very advanced Robocopy, Xcopy, or physical to virtual (P2V) migration tool. Double-Take Move isn't a replacement for Microsoft’s Exchange Server and Active Directory (AD) migration tools. For example, you can't opt to move just Exchange mailbox data to another server without moving the whole Exchange server and its configuration at the same time. Double-Take Move works at the file-system level; it's not application-aware. After a Migrate Server operation, the target has the same OS, system state, data, applications, and configuration as the source server.

Workload Portability
Double-Take Move migrates workloads between physical or virtual servers by using a simple workflow, one console, and most importantly, with minimal interruption to end users. Double-Take Move works with Windows Server 2003 SP1 and later. An example use of Double-Take Move would be to migrate an operational instance of Small Business Server (the workload) to new physical hardware. Double-Take Move can also be used for migrating data between different storage solutions (e.g., from DAS to a SAN).

Double-Take Move can provision new virtual machines (VMs) on Hyper-V or VMware ESX Server, to which you can migrate existing physical or virtual workloads. If physical hardware is used as the target, the OS must be preinstalled. Although hardware doesn't need to be identically matched, the target server must have a similar configuration, and Double-Take Move performs the necessary checks before starting a migration job.

Preparing Source and Target Servers
In my testing, I moved a Windows Server 2003 file server to a physical target machine with Windows 2003 preinstalled. The source server was a member of my AD domain and the target a standalone machine. You prepare the source and target servers for migration by pushing an agent to both machines through the Double-Take Move console, which Figure 1 shows. The only prerequisite is that the .NET Framework 3.5 SP1 be installed on the source and target servers.

Double-Take Move features two migration options: Migrate Data and Migrate Server. Migrate Data includes all selected data; Migrate Server includes selected data plus the system state and installed applications. I created a Migrate Sever job, which was a simple task using the wizard. When the source and target servers have been specified and checked for suitability, you can set options for compression and bandwidth throttling for migrations over a WAN and for excluding unwanted files and folders. The wizard maps NICs between source and target servers when they're on the same LAN, and NICs in the target server will have their IP addresses changed at the end of the migration process. For WAN migrations, NIC settings remain unchanged and Double-Take Move renames the target server and updates DNS records accordingly. Multiple migration jobs can run simultaneously, and each job can be configured with email notifications if required.

Migration
When a migration job starts, data is synchronized from source to target server. After a full sync completes, changes to source data continue to be applied to the target server until you're ready to start using it. Users access the source server until you make the switch, at which time critical modifications are made to the target system, such as NIC configuration changes and share creation.

When you click Cutover in the console window, the source server shuts down and the necessary configuration changes are made to the target. After a reboot, the target server comes online as if it were the source. Users can then continue to access resources without any knowledge that the server is running on different hardware.

In my testing, the whole procedure worked flawlessly, with only a few minutes when I wasn't able to access resources due to the cutover. The target server successfully rebooted as a member of my domain and was configured identically to the source.

Risk-Free Migration
Changes to critical IT systems are risky, and none are more so than migration. Double-Take Move is an impressive, no-fuss solution that has all bases covered. It eliminates the hazards associated with migration to new hardware, using mature technology with support for locked files. It's hardware-independent and even captures NTFS alternative data streams and transactions.