Why do certain packages fail in NetInstall? We are using NetInstall to image Macs at work. I build the NetInstall images with System Image Utility, and customize them with the "Add Packages and Post-Install Scripts" workflow item. NetInstall itself works great but I've noticed that several third-party install packages cause the imaging process to fail. A good example is Symantec Endpoint Protection.

My workaround has been to use JAMF Composer to snapshot an installation on a test machine to use that to create a new installer package. This works 99% of the time. However, I was wondering... What is it specifically about certain installation packages (.pkg files) that causes them to fail during the NetInstall process?
There can be several reasons for this. Probably the most common is that installer writers may not consider the possibility that their package might be installed on something other than the startup volume (i.e. with NetInstall, you're booted from a network volume but installing onto the local HD). The Installer application knows how to put the package's install files where they need to go, but if there are any associated scripts and such in the package, they may not cope with running from one volume and installing onto another.

Another (closely related) problem is that the package may have scripts that depend on resources that don't exist in a NetInstall environment. NetInstall runs in a pretty stripped-down version of OS X -- it includes everything most package scripts would need, but if they need something unexpected (like Finder, for example), they will fail and possibly cause the install to fail.