Backup databases - Use ChronoSync "dissect packages" option?

There are some old threads regarding the use of ChronoSync’s “dissect packages” option. However, there users seemed to try to use ChronoSync to sync DEVONthink database.

I want smaller backups. Most of my databases contain mainly indexed records, however e.g. the global inbox doesn’t - which means changing a single record results in a 5 GB global inbox backup.

Does someone use ChronoSync’s “dissect packages” option? Does it work? Which one exactly?

I don’t use ChronoSync but this option sounds especially dangerous if backups are created while databases are in use (or even modified at the same time).

Thanks!

If I test it (with closed databases) what should I look for to verify it does or does not work?

The only option is likely to restore a backup in a different location, to open the database and verify it (including the file integrity). However, the sync should be disabled first.

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First tests are looking promising! File integrity was always ok, thanks a lot for adding that!

As I’m probably not the only DEVONthink and ChronoSync user I’d really like to know other users’ experiences with this setting:

I have the same question regarding ChronoSync, and for the same reasons: smaller backups. While most of my databases are 2GB or much less, I have one huge database of 65GB that I want to back up but I balk at the inefficiency and resources spent backing up all 65GB just because I added a 25kB file. ChronoSync seems like the answer as it would back up only that single file of the database.

Of course, the assumption is that the backup is performed ONLY when the database is closed (in fact, I would not even have DT running at the time).

Basically, this question applies when using other software like Carbon Copy Cloner, which appears to also “dissect” the DT database files.

Given that for the case of databases created in FileMaker Pro there is no safe option other than full copies of the databases when closed because of the proprietary, monolithic nature of the FMP file format, we are given the hope that DT’s method of storing the original source files within DT’s “wrapper” where the source files are available for retrieval via the Finder, that maybe DT could tolerate ChronoSync’s “dissection” when backing up (assuming the databases are closed).

I and others would really like a formal assessment of this if possible. Thanks!

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I used to do this a lot with rsync, so here’s my experience.

If you do a one-way sync when the DB is closed, this is perfectly safe.

If you do a one-way sync while it is running, there is the chance that it will copy files over while they are in an inconsistent state. If your machine then crashed and you needed to restore from the backup, you would have an inconsistent db and the odds are good that a Verify & Repair will get you a working database, though you may have orphaned files and whatnot.

Where this gets into problem is when you are trying to do a two-way sync where files may be changed and databases may be open on both ends. That can really screw up the database. The good news is that your actual data files(e.g. pdfs) are going to be ok but the database can get totally messed up. So this one, don’t do it.

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Thanks for the response! I suspected this is the way it works, but it’s great to hear from someone with extensive experience.