Time Machine Backup Log

/ 14 December 2007

Earlier today I found the location in which Time Machine stores it’s log of activity. It stores the log within another one of the primary system logs (I don’t know exactly which one). Any log entry with the Sender “backupd” is from Time Machine. That makes sense as the underlying software behind the actual data transfer of Time Machine is called that. A standard Time Machine backup (done automatically and on my dad’s iMac) will produce this output. Please note that B747 is his backup disk, A320 is his boot/ internal disk, and Dreamliner is the computer name:

Backup requested by automatic scheduler Starting standard backup Backing up to: /Volumes/B747/Backups.backupdb No pre-backup thinning needed: 175.4 MB requested (including padding), 290.01 GB available Copied 57728 files (14.8 MB) from volume A320 Starting post-backup thinning Deleted backup /Volumes/B747/Backups.backupdb/Dreamliner/2007-12-13-162354: 290.78 GB now available Post-backup thinning complete: 1 expired backups Backup completed successfully

I’d expect that if the Time Machine preference pane said that a backup Failed then a hint would be in an entry like this. I found this set of entries by searching for the string “backup” in the All Messages log database query of the Console application. This means that we now know where to find the log that Time Machine writes when it performs a backup. Enjoy, Alex.

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