Managing Microsoft Windows Server 2003 Disk Storage : Configuring Disks and Volumes

Disk Management

Disk management activities are performed using the cleverly named Disk Management snap-in, which is part of the Computer Management console. Open the Disk Management snap-in in the Computer Management console, or add the snap-in to a custom console.

Disk Management can manage disk storage on local or remote systems. The snap-in does not manipulate disk configuration directly; rather, it works in concert with Dmadmin, the Logical Disk Manager Administrative Service that is started on the computer you are managing when you start the Disk Management snap-in.

The Disk Management interface is shown in Figure 1. The top frame—the list view—displays information about each partition, logical drive, or volume. The bottom frame—the graphical view—depicts disk space allocation per physical disk, as perceived by Windows Server 2003. You can right-click the volumes in either frame to access a shortcut menu to format, delete, or assign a drive letter to the volume. If you right-click an area of unallocated disk space, you can create a partition or volume. By right-clicking the disk drive’s status box, on the left of the disk’s graphical view, you can initialize a new disk, convert between basic and dynamic disks, and access the disk’s hardware properties dialog box.

Configuring Disks and Volumes

Configuring storage entails the following steps:

You must be a member of the Administrators or Backup Operators group, or have been otherwise delegated authority, to perform these tasks, although only administrators can format a volume.

Installing the Disk

To add a new disk to a computer, install or attach the new physical disk (or disks). Open Disk Management and, if the drive has not been detected automatically, right click the Disk Management node and choose Rescan Disks. If a system must be taken offline to install a new disk, restart the computer, then open Disk Management. If the new disks are not automatically detected, rescan the disks.

Initializing the Disk

When you add a disk to a server, you will need to initialize that disk before you can begin to allocate its available space to partitions, logical drives, and volumes. Initializing a disk allows the operating system to write a disk signature, the end of sector marker (also called signature word), and an MBR or globally unique identifier (GUID) partition table to the disk.

If you start the Disk Management console after installing a new disk, the Initialize Disk Wizard will appear automatically. To initialize a disk manually using Disk Management, right-click the disk’s status box and choose Initialize Disk.

Creating Partitions and Volumes

After you have initialized the disk, you can begin to implement a storage structure of partitions, logical drives, or volumes.

A newly initialized disk is configured by default as a basic disk. If you wish to maintain the disk as a basic disk, you can divide the basic disk into primary and extended partitions by right-clicking unallocated space and choosing New Partition. If you choose to create a primary partition, the partition becomes a logical volume. After creating an extended partition, right-click the partition again and choose New Logical Drive. As you’ll remember from earlier discussions, logical drives are logical volumes on an extended partition.

If you want to configure the disk as a dynamic disk, right-click the disk’s status box in Disk Management and choose Convert To Dynamic Disk. You can then right-click the unallocated space on the disk and choose New Volume. The New Volume Wizard will step you through the creation of supported volume types. The Select Volume Type page of the wizard is shown in Figure 2.

You can convert an existing basic disk to a dynamic disk—a solution that will be discussed later in this lesson.

Formatting Volumes

Windows Server 2003 supports three file systems: FAT, FAT32, and NTFS. Let’s keep this discussion simple: use FAT or FAT32 only when you have very specific reasons for doing so. Only NTFS gives you the level of stability, resiliency, scalability, flexibility and security required by most organizations. Many core components of Windows Server 2003, such as file security, and services, including Active Directory and Remote Installation Services (RIS), require NTFS. All advanced storage management tasks, including multidisk volumes and disk quotas require NTFS. If you think you need FAT32, think again, then think again.

Assigning Drive Letters or Mounting Volumes

When you create a volume, it defaults to the next available drive letter. The New Volume Wizard and New Partition Wizard give you a chance to specify an alternative representation for the new logical volume. You can also right-click an existing volume and choose Change Drive Letter and Paths.

A volume can be represented by only one drive letter, though you can configure a volume to have no drive letter. However, you can mount a volume in one or more empty folders on local NTFS volumes. In the Change Drive Letter And Paths dialog box, you can click Remove or Change to delete or modify an existing drive letter or folder mounting for the volume.

Click Add to add a drive letter or mount point. Figure 3 shows a server in which the Docs folder on the X drive is a mount point to another volume. Note that the folder appears in the Explorer namespace exactly where it should, but displays a drive volume icon. When a user navigates to that folder, the user is transparently redirected to the volume.

Figure 3. A volume mounted to a folder path

Mounting a volume in a folder on an existing volume effectively increases the target volume’s size and free space. You can mount volumes regardless of whether the volumes involved are on basic or dynamic disks, and regardless of what type of volume they are. But the empty folder, the path of which becomes the path to the mounted volume, must reside on an NTFS volume. The mounted volume can, technically, be formatted as FAT or FAT32, but of course that is not the best practice.

Extending Volumes

Another way to increase a volume’s capacity is to extend the volume. You can extend a simple or spanned volume on a dynamic disk so long as that volume is formatted as NTFS, and so long as the volume is not the system or boot volume. Right-click the volume and click Extend Volume. Follow the Extend Volume Wizard’s instructions screen to select unallocated space on dynamic disks on which to extend the existing volume. If you extend a simple volume onto space on another physical disk, you create a spanned volume.

You can extend a partition on a basic disk using the DISKPART command. The basic partition must be formatted as NTFS, must not be the system or boot partition, and must be extended onto immediately contiguous space on the same physical disk that is either unallocated and unformatted, or formatted with NTFS.

Moving Disks Between Servers

It is possible to move disks between computers. If, for example, you plan to take a server offline, you might attach its physical disks to another server so that data can continue to be accessed. The process for doing so is the following:

Some important notes about moving physical disks:

• If an imported disk contains volumes that span to other physical disks, you must attach and import all physical disks before the volumes can be accessed.

• If you move drives from several computers to a single computer, move all drives from one computer before beginning to move drives from the next computer.

• A basic volume that is moved to a new computer receives the next available drive letter. Dynamic volumes retain the drive letter they had on the original computer. If a dynamic volume did not have a drive letter on the previous computer, it does not receive a drive letter when moved to another computer. If the drive letter is already used on the computer where they are moved, the volume receives the next available drive letter.

• Use the Mountvol /n or the DISKPART automount commands to prevent new volumes from being automatically mounted and assigned a drive letter. If these commands have been used, when you add a new disk you must manually mount the volumes and assign drive letters or paths.

Converting Disk Storage

You can convert a basic disk to a dynamic disk. If the disk already contains partitions and logical drives, those units will be converted to the equivalent units for a dynamic disk: simple volumes. The structure of data on the disk is not modified, so it is possible to convert a basic disk that already contains data, although it is always best practice to back up volumes before performing disk management tasks.

To convert a basic disk to a dynamic disk, right-click the disk’s status box and choose Convert To Dynamic Disk. It’s that simple. If you convert a disk that contains a system or boot partition, the computer must restart.

Unfortunately, the reverse process is not as straightforward. Converting back to basic storage wipes out data on the drive. So you must first back up all data on the disk. Then you must delete all existing volumes on the dynamic disk before right-clicking the disk’s status box in Disk Management and choosing Convert To Basic Disk. After recreating partitions and logical drives, restore the data onto the disk. Although you can convert from dynamic to basic from a technical perspective, you are actually wiping out the disk and starting over.

Performing Disk Management Tasks from the Command Prompt

Windows Server 2003 provides command-line alternatives for disk management, including the following:

• Chkdsk Scan a disk for errors and, optionally, attempt to correct those errors.

• Convert Convert a volume from FAT or FAT32 to NTFS.

• Fsutil Perform a variety of tasks related to managing FAT, FAT32, or NTFS volumes.

• Mountvol Manages mounted volumes and reparse points.

But the granddaddy of disk management command-line tools is DISKPART. Table 1 summarizes the DISKPART commands that achieve common disk management tasks. Diskpart can be used interactively or can call a script. To start Diskpart interactively, type diskpart at the command prompt. When the Diskpart command prompt (DISKPART >) appears, type ? at any time for help. The command’s built-in documentation will appear automatically when needed to help you achieve the tasks you perform. Diskpart is also well documented in the Help And Support Center.

Practice: Configuring Disks and Volumes

In this practice, you will use the Disk Management snap-in and Diskpart to perform a variety of disk-management tasks on Disk 0. Disk 0 must be configured as a basic disk and contain at least 1 GB of unallocated space to complete this exercise.

Exercise 1: Creating a Partition Using the Disk Management Snap-in

Exercise 2: Converting a Disk from Basic to Dynamic Storage from the Disk Management Snap-In

Exercise 3: Using DiskPart

Exercise 4: Extending Volumes Using Disk Management

Exercise 5: Drive Letters and Mounted Volumes