###@See: How to use Rsync to synchronise directories Also, if you’re looking to synchronise Drupal files, you would be better using Drush rsync

rsync [options] Source [Source...] Destination

Rsync, which stands for “remote sync”, is a remote and local file synchronization tool. It uses an algorithm that minimizes the amount of data copied by only moving the portions of files that have changed.

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The -a option is a combination flag.

It stands for “archive” and syncs recursively and preserves symbolic links, special and device files, modification times, group, owner, and permissions.

It is more commonly used than -r and is usually what you want to use.

# Push changes to a server
rsync -a ~/dir1/ username@remote_host:destination_directory/

#Pull change to a local directory
rsync -a username@remote_host:/home/username/dir1/ place_to_sync_on_local_machine/