rsync synchronises a directory and everything inside it between two computers. In complexity and features, rsync is one step above scp (which copies individual files) and one step below svn (which maintains a version history and allows multiple people to collaborate). A modified version of rsync is the heart of Apple's Time Machine backup software.
Here is the basic use case for rsync: synchronising a folder between two machines, your desktop and jones.
1) To sync my local directory with the contents of the jones directory:
$ rsync -av username@jones.ling.indiana.edu:directoryname/ directoryname
NB:
- make sure the trailing '/' is after the directory
- v = verbose
- If your Mac files have resource forks (Spotlight-searchable metadata), you may need to add E to have it copied : -avE. I'm not sure this is still required in newer versions of rsync.
2) To sync the jones directory with my local directory:
- flip the arguments around, bearing in mind the '/' note
$ rsync -av directoryname/ username@jones.ling.indiana.edu:directoryname
3) Useful man page:
http://samba.anu.edu.au/ftp/rsync/rsync.html
rsync is also currently used to back up jones and smith. This use of rsync is much more complicated. The shell script can be found in the root directory of the backup drive; for Jones: /Volumes/Backup/backupUsers.sh