Stop Time Machine from Nagging About Every External Disk
A while back I posted a tip on a useful, but little known, preference setting for dealing with the Kerberos Agent dialog box. Today I'm posting another little known setting to handle an even more annoying box. The Time Machine "Use this disk for backup?" dialog.
The scenario is like this. Every time you plug in a different external disk Time Machine asks if you want to use it for backups. This is fine for the home user that can just click the No button, and get on with life. This is a giant pain in a managed deployment though as the setting is set per machine, not disk. Imagine if you have 3,000 Macs and 500 external disks that float around. That's a lot of nag windows and a lot of chances for users to screw up. What we need is a way to set a policy that tells Time Machine to not ask about every disk that is plugged in. That way we can guide the users to the correct result. Here it is:
defaults write com.apple.TimeMachine DoNotOfferNewDisksForBackup -bool YESAs with the Kerberos setting, I would push this with policy so that you don't need to touch every Mac by hand.