if you backup your *nix box, eventually you'll get into the business of purging your old backup files to preserve disk space. a reasonable way to do this is to use the find command to identify old backups and delete them. you should, however, consider doing something a little smarter than this.

the basic find method is usually accomplished with a statement like the one below, run from cron.

this would simply find and delete all files in the directory /var/myBackupDir that are older than 20 days.

you may, however, want to do something a little more sophisticated. what if your database got seriously corrupted 21 days ago? using the above technique, you would have 20 days of corrupted files.

i wrote a utility for smart purging of old backup files, purgeBackup. this utility allows you to list your desired set of backup ages e.g. {1 day, 2 day, 3 day, 10 day, 20 day, 40 day, 100 day}, and keep only the files that most closely match this specification. the statement that you'd use for this would be:

you'd similarly run this from cron, and each day, allow it to asses the optimum set of backups to keep.

purgeBackup will run in a simulation mode (no deletion) until you specify the --force argument, regardless, please exercise caution when using this utility.

here's the purgeBackup usage message:

purgeBackup - the source