Incremental backups using GNU tar
Need incremental backups? tar is just what you need in most cases.
Full backup of /etc: tar –create –file=full.tar –listed-incremental=snapshot.dat /etc
Incremental backup: tar –create –file=incr-01.tar –listed-incremental=snapshot.dat /etc
Here’s how it works: the option “–listed-incremental” will kindly ask tar to create a snapshot file containing all the modifications made to the files since the last backup. If the snapshot file does not exist, tar creates it and performs a full backup. Otherwise, tar will perform an incremental backup and update the snapshot file.