Saturday, March 12, 2011

Time Machine error (caused by Mac OS X Lion)

My Time Machine did not work today. I saw the following message:

Time Machine Error

I tried rebooting my mac and reformatting my external disk. They did not help. My external disk looks very healthy. There must be something wrong in Time Machine software.

In order to see what happened, I ran this command in the terminal window:

sudo grep backupd /var/log/system.log

I got many errors like this:

Mar 12 09:21:50 localhost[432]: Error: (-36) SrcErr:YES Copying /.DocumentRevisions-V100/PerUID/501/1/ to (null)

/.DocumentRevisions-V100 was created by AutoSave feature of Mac OS X Lion. I recalled I installed Lion on another partition and saved a file on Snow Leopard partition (to test AutoSave). Lion created that hidden folder on Snow Leopard partition and put the auto saved files there. However, the Time Machine software on Snow Leopard is not updated. It cannot recognize that system folder.
It is easy to fix this Time Machine error. Just exclude that hidden folder in Time Machine Preferences. (You need to enable 'Show invisible items'.) I actually excluded the following 3 hidden folders:/.DocumentRevisions-V100/.MobileBackups/.Spotlight-V100
Exclude folders in Time Machine My Time Machine is working again!This command "sudo grep backupd /var/log/system.log" is very helpful.


Reza Gorji said...

Thank you for this blog. I am also afflicted by the errors. I ran the terminal command and got this:
Jun 20 06:08:20 Reza-Gorjis-iMac-27-inch[55546]: Backing up to: /Volumes/Time Machine/Backups.backupdb
Jun 20 06:08:20 Reza-Gorjis-iMac-27-inch[55546]: Error: (22) setxattr for path:/Volumes/Time Machine/Backups.backupdb/Reza Gorji’s iMac 27 inch size:8
Jun 20 06:08:20 Reza-Gorjis-iMac-27-inch[55546]: Error: (-50) Creating directory 2011-06-20-060820.inProgress
Jun 20 06:08:20 Reza-Gorjis-iMac-27-inch[55546]: Failed to make snapshot container.

Any insight into this. I even called Apple Care and the gentleman could not help.

MacGeekNZ said...

Heya Vince. The shell command is useful indeed and it's how a true unix shell groker like myself would do the job, but a more "Mac like" way of accessing that information would via a GUI tool, ie the 'Console' app (located in /Applications/Utilities) to inspect the 'system.log' file. The Console tool has a built-in search feature which is easily used to filter for lines matching the string 'backupd'.

Thanks for sharing your info, it helps make the world a better place :)

Pete (Mac Geek from New Zealand)