Over-Allocating Disk Space
Applies To: Windows Server 2003, Windows Server 2003 R2, Windows Server 2003 with SP1, Windows Server 2003 with SP2
Some tasks, such as moving large folders within a disk volume, require a user to temporarily allocate a large amount of disk space. This temporary space is more readily available if it is pulled from a large pool of space. Therefore, you need to allocate more space for each user than they need for long-term storage.
Determination of the total quantity of shared disk space to be made available to users is influenced by historical requirements, planned deployments of new servers and user accounts, and your hardware purchasing budget. Typically, the median disk usage is much higher than the average disk usage due to the varying allocations of disk space in a large group of users.
Requirements for Managing Disk Quotas
Disk quotas track and control disk space usage for user data that is stored on the network. You can set disk quotas by using Group Policy. When disk quotas are enabled in Group Policy, the settings affect all NTFS volumes on all computers running Windows 2000, Windows XP Professional, or Windows Server 2003 to which the GPO applies. Alternatively, you can manually set disk quotas on individual servers.
To administer disk quotas, you must be a member of the Administrators group. You can set quotas on local volumes, network volumes, and removable drives that are formatted with NTFS. The network volumes must be shared from the volume’s root directory, and removable drives must be shared.
Recommendations for Using Disk Quotas
Apply disk quota limits according to the actual disk space your users need.
Try to estimate how much disk space various types of users will require and then categorize users according to their disk space requirements (for example, users who work with art programs might require a large amount of disk space).
Next, structure your disk volumes by those categories, and then use disk quotas to limit the amount of disk space allowed for the users on each volume.
Also, consider metadata. Each file stored on the volume can use up to 64 kilobytes (KB) of NTFS metadata that is not applied to a user’s quota limit. To avoid running out of disk space, ensure that you provide sufficient disk space to accommodate this metadata.
Setting default quota limits
Set moderately restrictive default limits for all user accounts, and then modify the limits to allow more disk space to users who work with large files. You might want to increase disk quota limits for a few user accounts rather than to force some users to work with a quota limit that does not meet their needs. User policy settings occupy at least 2 MB of disk space, so you should set the default limits for all user accounts above 2 MB.
Setting limits that permit growth in disk space use
Set the quota level to allow for increasing use of disk space. Increase quota when necessary as a percentage of the current quota setting.
Group Policy for Disk Quotas
Table 7.19 lists the Group Policy settings for disk quotas. These settings are available in the Computer Configuration\Administrative Templates\System\Disk Quotas node.
Table 7.19 Disk Quota Policy Settings in Disk Quotas
| Policy Setting | Description |
|---|---|
Enable disk quotas |
Enables and disables disk quota management on all NTFS volumes of the computer and prevents users from changing the setting. |
Enforce disk quota limit |
Determines whether disk quota limits are enforced and prevents users from changing the setting. |
Default quota limit and warning level |
Specifies the default disk quota limit and warning level for new users of the volume. |
Log event when quota limit exceeded |
Determines whether the system records an event in the local Application log when users reach their disk quota limit on a volume, and prevents users from changing the logging setting. |
Log event when quota warning level exceeded |
Determines whether the system records an event in the Application log when users reach their disk quota warning level on a volume. |
Apply policy to removable media |
Extends the disk quota policies in this folder to NTFS file system volumes on removable media. |
Group Policy for Disk Quota Processing
Administrators can use Group Policy to specify how often disk quotas are applied. The Disk quota policy processing policy setting is available under Computer Configuration\Administrative Templates\System\Group Policy. This policy applies to all policy settings that use the disk quota component of Group Policy, such as those in Computer Configuration\Administrative Templates\System\Disk Quotas.
The Quota policy processing policy setting includes the following options:
Allow processing across a slow network connection. Updates the policies even when the update is being transmitted across a slow link. Updates across slow connections can cause significant delays.
Process even if the Group Policy objects have not changed. Updates and reapplies the policies even if the policies have not changed. Many policy implementations specify that they are updated only when changed. However, you might want to update unchanged policies, such as reapplying a setting in case a user has changed it.
Do not apply during periodic background processing. Prevents the system from updating affected policies in the background while the computer is in use.
Caution
- Background updates can disrupt the user, cause a program to stop or operate abnormally, and, in rare cases, damage data.
Administrators and users with rights to create computer objects can circumvent quota restrictions. This is because they can create any number of computer accounts, each with the default quota limit.