Lessons Learned: Slow Link Detection

Environment: Multi Site Windows 2000 Domain with several remote locations** **

Task: Deploy software to the enterprise using Group Policy** **

Problem: After implementing the Group Policy to assign software, some users complained that no software was installed

Troubleshooting: Users complaining that no software was installed were from different OUs and different Sites. There was no apparent relationship between these users. There were no improperly configured of GPO links, filters, or security, therefore troubleshooting proceeded on a user by user basis. Having a few users run RSoP.msc showed that they were, in fact, getting the policy. OK then, why isn't the software installing? A remote connect to the user's Event Viewer timed out. Remote connections to all of the workstations being tested timed out. Now we're getting somewhere. All of the users who were not receiving software were remote locations with very slow connection speeds. But why would only some of the settings in a Group Policy apply and others not apply? Searching Google returned something very interesting. If it is determined that a workstation is connecting to a DC over a slow link, Folder Redirection, Scripts, and Software Installation settings are not processed. Cause identified! 

Resolution: There is a Group Policy setting that allows for configuring the Slow Link Detection threshold and which settings will or will not apply in the event a slow link is detected. The software packages we were intending to install were of considerable size, and testing at one remote location produced results that were never really considered. The software installation took hours and rendered the workstation unusable during the process. The fix for this problem was disappointing from a technical perspective, but practical. CDs containing the .msi packages were shipped to the remote sites for local installation. 

As a result, we were now familiar with Slow Link Detection and considered it whenever deploying GPOs to remote locations. 

Slow Link Detection http://support.microsoft.com/kb/227260

Specifying Group Policy for Slow Link Detection http://technet.microsoft.com/en-us/library/cc781031(WS.10).aspx