Cardbox > Support > Knowledge Base ...

Filenames of Amazon S3 Backups

This information relates to Build 163 or later of the Cardbox Server and Build 4299 or later of Cardbox. Earlier builds.

There are now many utilities available which will read the contents of Amazon S3 buckets and allow you to manage the objects within them. If you want to use one of these tools, you need to know how the Cardbox Server creates objects to serve as backups of Cardbox databases.

The Cardbox Server constructs the object name to use for an Amazon S3 backup as follows:

  1. It takes the name of the database. (If you have set up databases to have one name for the user and another name as disk files, it is the user-visible name that is used here).
  2. It adds .fil to it for the database file, or .fmt for the format file.
  3. If you have specified that all versions of the backup should be kept (and not just the most recent one) then it adds an @ sign followed by the date and time in year.month.day.hour.minute.second format. If you have asked for only the latest backup to be kept, nothing happens.
  4. If the file being backed up is more than 1GB in size, it is broken into 1GB chunks. The first chunk's name is unchanged, but each chunk after the first has a suffix #1, #2, and so on.

For example, if a database called "Customers", stored on disk as cust.fil, last modified at 4pm on 14 January 2012, is backed up, the object name will be Customers.fil@2012. If you have asked for only the latest backup to be kept, the object name will be simply Customers.fil.

Earlier builds

Earlier builds of Cardbox and the Cardbox Server followed exactly the same rules except that they used non-printable characters in place of the @ and # signs. This works with Amazon S3 but standard tools do not support it: they report a corrupted bucket and don't list anything.

The current builds of Cardbox and the Cardbox Server will use the new object name format but they will understand the old format as well, so all your backups are safe.

If and only if you want to make your existing backup bucket accessible to other Amazon S3 utilities, you will have to look at it in Cardbox, with the command Tools > Management > Amazon S3. You need to delete any backup files more than 1GB in size and any backup files which have an entry in both the "Date" and the "Backed up" column.

If you only want to carry on accessing your backups through Cardbox, there is nothing you need to do.

© 2016 Martin Kochanski
"Cardbox" is a registered trademark.
 Top of page