I am trying the following command using rsync to copy only files thatare newhave a different sizersync -niav --size-only   /home/me/source/Electronica  /media/externalDrive/dest/ElectronicaHowever, this dry-run results in the following output: >f+++++++++ Electronica/music/AlbumArt_{F0CB439F-A1FC-47DB-A698-C561191F3FDE}_Large.jpg>f+++++++++ Electronica/music/AlbumArt_{F0CB439F-A1FC-47DB-A698-C561191F3FDE}_Small.jpg>f+++++++++ Electronica/music/Folder.jpgwhich I interpret to mean that those files are copied. But they have the same size! (The times and flags are different, though). Also the rsync refers to an external hard-drive (with a different format). I also tried the following commands: rsync -niav --size-only --ignore-times  /home/me/source  /media/elsersync -niav --size-only --ignore-existing /home/me/source  /media/elseBut still, these files are shown in the same way, meaning they would have copied. What else can I try?And what is wrong with the main page description?--size-only     skip files that match in size
rsync wants to copy files that already exist in the destination directory
rsync
You've fallen into rsync's classical trailing slash trap:If the source path does not end with a slash, rsync will copy the source directory. If you intend to copy the contents of the source directory, it needs to end with a slash.Let's look at an example, assuming you want to copy a file at /home/me/source/Electronica/music/Folder.jpg:rsync -a /home/me/source/Electronica  /media/externalDrive/dest/Electronicawill copy the Electronica directory from the source to the destination, so it will create /media/externalDrive/dest/Electronica/Electronica/music/ and put Folder.jpg in there.rsync -a /home/me/source/Electronica/  /media/externalDrive/dest/Electronicawill copy the contents of the Electronica directory, so it will replicate the music directory under /media/externalDrive/dest/Electronica/ (if it doesn't exists) and Folder.jpg will end up at /media/externalDrive/dest/Electronica/music/Folder.jpg.To make matters more confusing, it does not matter if the destination path ends with a slash.Just make a habit of ending all rsync paths with a slash, then you'll be safe from any nasty surprises.