Q We have some ten Macs that save their work in progress to a central file server, but individual Macs do not make any backups beyond those. Should we use Time Machine on each of those to make, say, a weekly complete backup to an external drive?
A If you are happy that all their working documents are being properly backed up on the file server, then you need to consider the best strategy for backing up other material such as email, and how to recover if one of those Macs were to die suddenly.
The most sensible way of doing this is to look at each system in turn, finding out what is not stored on the file server, how valuable it is to your business, and how often it changes significantly. Look also at how differently each is configured in terms of applications and settings. You may find that the best approach is to make a complete image of each to an external store, so that you can use those for recovery purposes, and then just to back up the contents of Home folders every day or so, to cover email and the like.
Time Machine is designed to make an incremental copy of all changed files every hour, which is probably excessive for your purposes, although you can alter that frequency using third-party tools such as TimeMachineEditor (free). It is also far from an ideal tool for network backups, making it preferable to keep an external drive attached to each Mac if they cannot have additional internal disks installed. You can at least narrow the range of folders that it backs up, but that would seem to defeat its best purpose.
Updated from the original, which was first published in MacUser volume 26 issue 4, 2009.