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Take Symantec's Ghost: It allows direct-to-tape duplication--a nice touch that lets you store many images cheaply, which is great if you have clients with diverse workstation needs. PowerQuest's DriveImage accommodates spanning and compression of disk images, and allows for file extraction from an image.

For the most part, deployment with these tools remains unchanged: Use a network boot disk, run DOS-based software and grab an image from the network. Multicasting changes the rules somewhat and can load multiple workstations without increasing network use. But be careful--not all tools use IP multicasting like Ghost does. Ethernet-specific tools such as ImageCast use media-level broadcasts, so you should be wary of creating broadcast storms on large switched Ethernet networks.

Most initial duplication deployments we've seen have a session where all the workstations start complaining about duplicate network names, IP addresses and so on. Although you can deal with IP by using DHCP, other parameters can't, so each workstation ends up being touched by a technician before rollout.

Duplication software's postconfiguration options can make this a thing of the past. You can use custom boot disks for every workstation you roll out, as with ImageCast, and wonder why you're playing the '80s floppy shuffle, or you can go with software that gets configuration options from the network. For example, KeyLabs' RapiDeploy console will run on any workstation and will queue configuration jobs and drive images to any workstation running the RapiDeploy client.

After the Dust Settles Experience--and Microsoft--say that duplication is best done in batches of similar hardware on a departmental or group level, with as much preduplication configuration as possible. But even if you install and configure applications to the hard drive before duping, the time will come when applications get upgraded and added to an existing group's workstations.

This is where software deployment tools can augment duplication. These tools learn how a system changes when an application (or any other process) modifies the workstation environment; they apply these changes to other workstations that started out the same, letting you roll out single applications or patches without having to touch workstations.

But these tools present their own challenges, such as the need for a clean (no apps installed) workstation every time a system administrator adds a snapshot. And just as software management tools help duplication efforts, duplication tools help with software management. Since it sometimes takes a couple of tries to get a snapshot right, it pays to make the cleanup process efficient. Instead of re-duping from the network, you should set up a workstation with multiple hard drives or partitions and keep a clean image file on one partition. This way, you can quickly redo the boot partition locally between retries, which takes far less time than if you go to the network.

Jonathan Feldman is technical systems manager for the Chatham County government in Savannah, Ga. Send your comments on this article to him at jfeldman@nwc.com.