Disk quota management arrives at last

Even though today's enterprise file servers offer more and more disk space, users still find ways to fill all the storage you give them. I'm sure you all have storage hogs, who despite constant prodding by your network managers, still keep the last four years of their personal e-mail on the server (replete with scores of 50MB PowerPoint file attachments) and those who feel that your $30,000 box with 100GB of RAID-5 or SAN storage is their personal Napster service.

Since NT was first released in 1992, Microsoft never gave NT administrators a way to regulate user storage quotas. Other network operating systems, such as NetWare, had storage quota management built into the system for years. Even when NT tipped the scales and gained dominance, the OS still lacked storage quota capabilities.

This left the market open for products like NTP Software's Quota Manager, W. Quinn's QuotaAdvisor, Advanced Toolware's Spaceguard and NORTHERN Software's Quota Server. Products like these use policy-based management through administrator-definable access control lists and file system device drivers to set limitations on user storage. Unfortunately, at several hundred dollars per copy, the per-server licensing costs kept these add-on administrative products from becoming de rigueur at small to moderate-sized IT shops.

While upper management mandated the use of other add-on products, such as network virus scanners, only administrators clamored for storage quota management. Stu Sjouwerman, president of Sunbelt Software, a leading distributor of third-party tools for Windows NT, tells me that only 15 to 20 percent of NT shops use third-party quota management tools, which leaves most NT admins in the unpleasant position of having to handle storage issues in a reactive rather than a proactive mode.

Jason Perlow is a computer industry freelance writer covering Windows 2000 and Linux.Fortunately, Microsoft finally implemented quota management as one of the base features of the NTFS 5 file system in Windows 2000. With Quota Management, you can set default user storage limits on a per-volume basis and override these defaults on a per-user basis.

To turn on Quota Management, double-click the My Computer icon on your server's desktop. Right-click the disk volume you wish to enable quotas on, and select Properties from the pop-up menu. Click the Quota tab to get to the Quota panel, and in Quota Properties, select Enable Quota Management.

In addition to enabling Quota Management on a volume-wide basis, you can set quota values for all users by default. To assign default quota values for users, insert a value in the "Limit Disk Space To" option. You can use numeric or decimal values such as 1.8MB, 3GB, or 500KB. Click OK when finished.

You can further customize quota options to deny disk space to users exceeding the quota limit, log events when users exceed quota limits, and log events when users exceed warning levels.

You can override the default values and create volume quota entries for specific users by clicking on the Quota Entries button in the Quota panel. You can use the Quota Entries applet to export and import quota rules to and from other servers and volumes, as well as generate usage reports per user.

While the built-in quota management of NTFS 5 is a vast improvement over the complete absence of such tools in previous versions, it's still not as robust as most third-party tools. For example, the built-in tools work on a per-volume and per-server basis, but can't apply quota policy across your Windows 2000 network. The tools can only make exceptions on a per-user basis, as opposed to applying policy to groups of users, or applying different policies to different share points and directories. The built-in tools can't notify users of their disk usage based on definable threshold levels; users receive a single "disk full" error when they hit their limit.

Both W. Quinn's Quota Advisor (about $600) and NTP's new Quota Sentinel (about $700) have the features to fill these voids and other omissions. Quota Sentinel, for example, uses a sophisticated policy-based management tool to restrict filtered file types, such as MP3 and Visual Basic scripts, from being written to the network. It can also hook into the Active Directory to manage Exchange quotas.

Quota management and storage management may be a bottom-up request from your NT admins, but any good IT manager making the move to Windows 2000 should seize the day and take advantage of these tools. You may have more storage than you know what to do with, but putting limits on storage now alleviates problems that will pop up later.