MacOS – Spotlight disappeared when I updated

You likely ran into a problem with the Thunderbolt Update 1.2 - it's not clear how often this is causing problems (or if the problem was pre-existing and the update process just surfaced it or if the update itself has a problem).

Your best bet for up to date service information is contacting Apple support - especially if you are covered and it's a free request.

Next would be some of the long time Apple blogs like Tidbits that has some very good reporting on this so far.

• https://twitter.com/TidBITS/status/212548049342431232
• https://twitter.com/TidBITS (for updates)

You might booting from an external drive (or reinstalling to an external drive and reapplying the combo update 10.7.4 to the failed drive while booted from another install of Lion) to see if you can avoid total reinstallation.

Have you tried disabling spotlight on the device per terminal command?

Something like sudo mdutil -i off -d -E <mountpoint> to disable indexing, searches and to erase spotlight caches on the drive.

According to your output /Volumes/Backup has it disabled but /Volumes/Backup/Backups.backupdb hasn't, it may make a difference to run the command with that mountpoint.

Another solution suggested here is to stop the spotlight process entirely. You could do this with kill <procid> or launchctl. You can re-start it after ejecting the drive.

(The procid for the kill command is the one in the second column of your lsof results, or you can alternatively use use ps -ax | awk '/[m]ds/{print $1}' to get the procids for mds and mds_store.)