Just Enough Developed Infrastructure

Moving from Rsync on Unix to Rsync on MacOSX

I use rsync alot on unix machines. It is a versatile tool that allows you to:

  • save bandwith: when synchronizing multiple machines, it will only the changes, optionally compressing the files with the '-C' option
  • make incremental backups: using the --link-dest option, you can synchronize your data everyday to a new directory (backup-dayX) and avoid that it will copy all data and take up diskspace for every backup.
Rsync is by default included on MacOSX. But using when rsync on mac, there a few caveats:
  • extra flags are lost: Mac filesystem has a notion of data and resource forks. Also the HSFS filesystem has extended attributes. So if you are synching with a samba or other non-mac filesystem aware system, this information will be lost. Apple provides a 'rsync -E' command for this.
-E, --extended-attributes Apple specific option to copy extended attributes, resource forks, and ACLs. Requires at least Mac OS X 10.4 or suitably patched rsync.