Chapter 6. Mass Deployment

Chances are that if you deal with enterprise-level systems management you'll need to deploy systems en masse from time to time. If you have a hardware refresh rate of, say, 25 percent per year and a total of 10,000 computers, you'll have to deploy 2,500 machines every year. The tasks involved in the process are usually repetitive, lending themselves to batch processing. As a result, you can—and should—put solutions in place that let you automate deployment of systems on an ongoing basis.

If planned properly, you can extend the file sets and tools you develop, using them to provide everyday troubleshooting capabilities. For example, suppose a problem is resident on only one computer, but the symptoms present themselves across multiple users. Many IT departments have a policy of simply reimaging such systems, on the assumption that the computer in question has somehow varied from an approved image. This may seem counter intuitive, and an entry-level troubleshooting technique, however while it may technically satisfying to isolate an issue on a machine, doing so may be take much more time than simply reimaging a system. In this way, the user has less down time because you have cloned the same configuration on to all machines, so if an issue only presents on one, the chances of it being systemic are low. In most organizations, reimaging as part of a troubleshooting paradigm can sharply reduce the Total Cost of Ownership (TCO) while simultaneously serving to keep the environment as homogenous as possible (which further reduces TCO).

To reduce the time spent reimaging, it's a good idea to keep user data in sync with or stored on another host or segmented from the system in some fashion, such as a dedicated partition for user data, or utilizing Apple's external account technology. In Microsoft Windows, this would commonly be accomplished using roaming profiles. In the Apple enterprise vernacular, there are two similarly common options for user data storage, Portable Home Directories and Network Home Folders. This helps save your support personnel from either having to back up each user folder or computer prior to reimaging or replacing a system. One of the goals of implementing an imaging solution should be to reduce the amount of time spent fixing problems. Commoditizing computers will help you to achieve that goal. In Chapter 7, we'll cover portable and network home folders.