Using the Time Machine preference pane, it is not possible to effectively exclude the data for the Software Update service from Time Machine backups on Mac OS X Server 10.6. A method is presented here which will do that.
By default the software downloaded from Apple’s servers necessary for the Software Update service is located at /private/var/db/swupd. When excluding this directory using the Time Machine preference pane the path is changed to /var/db/swupd (/var being a symbolic link to /private/var) and the data is still backed up.
[crarko adds: This is for Snow Leopard Server only.]
To remove the Software Update service data from the backups, follow these steps using an administrative account:
sudo -s cd /Library/Preferences plutil -convert xml1 com.apple.TimeMachine.plist pico com.apple.TimeMachine.plist
Mac OS X Hints
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