Is it possible to ask Spotlight to not index a volume ?
Yes, open the Spotlight prefpane and under the Confidentiality tab (not sure, but on my French system it is called "Confidentialité"), you can add folders and volumes not to be indexed.
There are a variety of options to do this:
- Add the drive to the "Privacy" tab in the Spotlight Preference Pane
- Turn off Spotlight indexing for the site from the command line:
sudo mdutil -i off /Volumes/NAME_OF_DRIVE
touch /Volumes/NAME_OF_DRIVE/.metadata_never_indexon an external drive.
If it's a removable volume, create a file in its root directory called .metadata_never_index, as in this hint.