Mission: To backup my music and picture collection onto portable hard drives as a backup .
Music: 406.66 GB
Pictures: 57.86 GB
The pictures folder is updated every two or three days with pictures from my iphone and the occasional run with my SLR.
The Music folder is updated multiple times a day with podcasts and other downloads.
To copy the entire folders to an external USB 2 drive would take most of the night. This is simply not practicable, at least until USB 3 comes along.
Even then it makes more sense to only copy the changes.
The solution, RSYNC
Original disk: work ==> backup disk: backup500gb
>>> sudo rsync -vaxE –delete Music /Volumes/backup500gb
This would recursively transfer all files from the directory
/Volumes/work/Music to /Volumes/backup500gb/Music directory.
The files are transferred in “archive” mode, which ensures that symbolic links, devices, attributes, permissions, ownerships, etc. are preserved in the transfer. Additionally, compression will be used to reduce the size of data portions of the transfer.
The archive mode is overkill for pictures and music, but if I were copying programs, batch files, etc it would be very important.
-v, --verbose increase verbosity -a, --archive archive mode; equals -rlptgoD (no -H,-A,-X) -x, --one-file-system don't cross filesystem boundaries -E, --executability preserve executability
>>> sudo rsync -vaxE –delete Pictrures /Volumes/backup500gb