Managing Printer Publishing and Pruning Through Group Policy
The policies associated with printer publishing and pruning are well documented elsewhere. In particular, the Microsoft white paper "Integration of Windows 2000 Printing with Active Directory" (http://www.microsoft.com/windows2000/docs/printad.doc) and the Microsoft article "Using Group Policies to Control Printers in Active Directory" (http://support.microsoft.com/?kbid=234270) serve as good resources.
The default Group Policy settings work well for most AD environments, but if you have persistent problems with publishing or pruning, changing a few specific policies might help. As Figure 6 shows, you find the settings associated with printing and pruning in the Group Policy console under Computer Configuration, Administrative Templates, Printers. If you have severe problems with printers being pruned unnecessarily (e.g., because of network problems), I suggest that you first try increasing the Directory pruning interval. If that doesn't solve the problem, then increase the Directory pruning retry. You can also enable Check published state and set it to an appropriate value—12 hours should be sufficient. This last setting is particularly useful because it causes print servers to republish pruned printers without you having to restart the spooler on the print server. Be careful not to set this value too low—frequent spooler restarts might adversely affect server performance.
I don't recommend switching off printer pruning altogether because you could end up with orphaned printer information in AD. However, if you really want to do so, the setting to change is Allow pruning of published printers (set this value to Disabled).
A difficult decision arises with regard to the Group Policy pruning settings for manually published printers. If you allow pruning for these printers, you'll probably need to manually republish the printers from time to time, which can be both annoying and time-consuming. However, if you disable pruning for these printers, you'll most likely end up with orphaned printers in AD. You also don't have the option to use the Check published state setting because this policy works only with print servers that can automatically publish printers. A compromise would be to place manually published printers in a separate, dedicated organizational unit (OU) linked to a policy with higher than usual Directory pruning interval and Directory pruning retry settings. It's also a good idea to set the Allow printers to be published policy setting to No for your workstation OUs, which makes the List in the Directory check box unavailable.
Learning Points
The introduction of printer publishing in AD provides a handy way for users to quickly locate nearby printers. The many printer-related attributes stored in AD let your users carry out detailed searches for printers with specific features. For the Find Printer service to be effective, you must carefully plan and manage the printer publishing and pruning mechanisms. Pay particular attention to the Location-field naming schema because it largely determines the effectiveness of users' printer searches.
The publishing and pruning mechanisms aren't always trouble free, so you need to understand how the mechanisms work, the types of problems to watch for, and how to troubleshoot them. Fortunately, tools such as EventCombMT are available to help.
In addition, Group Policy settings let you control most publishing and pruning behavior. You should occasionally review and, where appropriate, modify the settings as your AD environment grows and changes.