Setting Up and Using Home Server Storage : Who Needs Drive Extender? Implementing Spanning, Mirroring, and RAID (part 1) - Creating a Storage Pool Using a Spanned Volume

Creating a Storage Pool Using a Spanned Volume

One of the best features of Drive Extender (indeed, one of the best features in all of Windows Home Server version 1) was the dynamic storage pool. If you installed a new hard drive on the server, you could then add that drive to the existing drives and instantly get a larger storage pool for client backups and shared folder data.

Alas, Drive Extender now resides in the trash bin of technology history, so you have to deal with fixed disk sizes in Windows Home Server 2011. This can be a particular problem with client backups because they tend to take up a lot of disk space, and if the server drive that stores the backups gets full, subsequent backups will fail.

That is, to say the least, not good, so you’re forced to look for other solutions. Fortunately, one such solution sits right under your nose as a feature of Windows Server 2008 R2: a spanned drive. This is a kind of virtual drive—or volume, as Windows Server calls it—that combines two or more physical hard drives into a single storage area with two main characteristics:

• The new volume is dynamic because if you install more drives on the server, you can add those drives to the volume to instantly increase the storage area without losing any existing data.

• The new volume is spanned because data is seamlessly stored on all the physical hard drives without your having to worry about where the data is stored. If one of the hard drives fills up, Windows Server automatically writes new data to one of the other drives in the volume.

In other words, a dynamic, spanned volume is a reasonable facsimile of the storage pool feature of Drive Extender. Is there a downside to using spanned volumes? Yes, unfortunately, there are two:

• If one of the hard drives dies, you lose all the data stored in the spanned volume, even data that resides on the remaining functional drives.

• If the total size of the spanned volume exceeds 2TB, you won’t be able to back up the volume using the Server Backup feature of Windows Home Server 2011 (because Server Backup has a 2TB maximum for any volume).

In other words, if you go this route, I strongly recommend that you come up with some other way to back up the spanned volume to prevent data loss (for example, by installing a third-party backup program on the server).

Converting Hard Drives to Dynamic Disks

To get started, your first chore is to take the hard drives that you want to use for the spanned volume and convert them to dynamic disks:

Combing Dynamic Disks into a Spanned Volume

With your dynamic disks converted, you can now combine them into a spanned volume by following these steps:

1.	Log on to the Windows Home Server machine.
2.	In the taskbar, click Server Manager to open the Server Manager window.
3.	Select Storage, Disk Management to display the Disk Management snap-in.
4.	In the list of hard drives in the lower half of the Disk Management pane, right-click one of the drives you want to include in the spanned volume. Be sure to right-click on the left side of the drive display (where you see the disk designations, such as Disk 1, Disk 2, and so on).
5.	Click New Spanned Volume. Disk Management runs the New Spanned Volume Wizard.
6.	Click Next. The Select Disks dialog box appears.
7.	In the Available list, click a dynamic disk you want to include in the volume, and then click Add. Note You don’t have to include the entire dynamic disk in the spanned volume. For example, you might want to set aside a portion of the dynamic disk for other storage uses. In that case, click the disk in the Selected list, and then use the Select the Amount of Space in MB spin box to set the amount of space you want to assign to the spanned volume.
8.	Repeat step 7 to add any other drives you want to include in the volume. Figure 2 shows a spanned volume with two dynamic disks added. Figure 2. Add the dynamic drives that you want to include in the new spanned volume.
9.	Click Next. The Assign Drive Letter or Path dialog box appears.
10.	Choose a drive letter (the default will probably be D:, which is fine), and then click Next. The Format Volume dialog box appears.
11.	Assign a Volume Label, if needed, leave the other options as is, and then click Next. The last wizard dialog box appears.
12.	Click Finish. Disk Management creates the spanned volume.

Figure 3 shows how the new spanned volume (drive D:, in this case) appears in Disk Management (the top window) and in the Computer folder (bottom window).

Figure 3. The new spanned volume shown in the Disk Management snap-in and the Computer folder.

With your spanned volume at the ready, you can move Windows Home Server’s Client Computer Backups folder from its default location to the spanned volume. 

Adding another Dynamic Disk to the Spanned Volume

If you install a new hard drive on the server, you can add that drive to the spanned volume. Open the Disk Management snap-in and convert the new drive to a dynamic disk, as I described earlier. Now follow these steps to add the new dynamic disk to the spanned volume: