# Can I safely use Time Machine to backup my catalog?



## Jean-Claude (Mar 22, 2013)

I'm in the process of setting up a complete backup and archiving strategy for my computer.  I would like to use Time Machine for versioned backups and Carbon Copy Cloner to make a bootable clone.  Advice given about using Time Machine to backup a Lightroom catalog differ from website to website.  It's difficult to get a clear and definitive answer. 


Some say Time Machine shouldn't be used at all to backup the catalog because if the catalog is in use during the backup, it will get corrupted.
Others say it doesn't matter if Time Machine creates a corrupt catalog because, since it creates a backup every hour, it will create a good backup when you quit Lightroom.
There are those who say Time Machine can be used safely because it automatically excludes the catalog if it is in use, and backs it up when it is closed.
Some say it doesn't make sense to back up the catalog every hour because it can fill up the backup drive too quickly.

Is there someone in this forum who has the official word on how Time Machine and Lightroom work together?


----------



## clee01l (Mar 22, 2013)

I don't know how official it is but I successfully use LR and TM. As some have pointed out,  an active catalog is in an unstable state. If it gets backed up by TM (and there is some indication that TM will not back up an open file), the file you recover may be corrupt. And since the Previews folder is large and a backup is not needed, I exclude my catalog folder from the TM backup. I continue to use the built-in backup in LR to make catalog copies and these will be my first fallback in case of catalog failure. 
So my scheme official or not, works well and is easy to implement. Without specifically answering your question, if you use the scheme that I outlined, you will be covered and the answer to your question really does not matter.


----------



## Mark Sirota (Mar 22, 2013)

Time Machine can be used with Lightroom, with one caveat.

Your first bullet is not entirely correct. If the backup runs while Lightroom is open, the real copy of the catalog will not get corrupted. It will be unaffected. However, the copy written to the backup will not necessarily be usable. When recovering a catalog from a Time Machine backup, you need to confirm that it was made while Lightroom was not running.

This is easy to do -- when recovering a backup from Time Machine, check to see whether there is a .lock file alongside. If there is, recover from the next older backup.

As with any backup scheme, you should test the recovery process to ensure that it's all working and that you know how to do it.  That's really the best way for you to answer your own questions.

That said, if you have Lightroom back up when you exit, then you can safely eliminate Lightroom catalogs from your Time Machine backups, assuming the backup catalogs are included. Then when you recover from Time Machine, pull one of the backup catalogs rather than the running catalog. (That's more or less what Cletus said.)


----------



## Victoria Bampton (Mar 22, 2013)

The working catalog shouldn't get corrupted, but if TM backed up while LR was open, the resulting backup could be corrupted.  It's one of those things that's difficult to say categorically, because TM can make changes without us ever knowing.

My general suggestion is to let LR backup the catalog, and let TM backup those backups.  Then you're definitely safe.


----------



## Brad Snyder (Mar 22, 2013)

LOL, that's a data communication maxim:

I tell you 3 times!
I hear you 3 times!


----------



## Jean-Claude (Mar 22, 2013)

Got it!!  Thanks everyone for your help.


----------

