01orb

rsync -r dir1/ dir2
# -r: recursive
# This trailing slash(/) signifies the contents of dir1. Without the trailing slash, dir1, including the directory, would be placed within dir2. 

rsync -a dir1/ dir2
# -a: archive. recursively and preserves symbolic links, special and device files, modification times, groups, owners, and permissions.

rsync -anv dir1/ dir2
# -n or --dry-run
# -v: verbose

rsync -a ~/dir1 username@remote_host:destination_directory

rsync -a username@remote_host:remote_directory local_directory

rsync -az source destination
# -z: compress

rsync -azP source destination
# -P: --progress and --partial
# --progress: progress bar
# --partial: allows to resume interrupted transfers

rsync -an --delete source destination
# --delete: delete

rsync -a --exclude=pattern_to_exclude --include=pattern_to_include source destination
# --exclude=pattern_to_exclude
# --include=pattern_to_include

rsync -a --delete --backup --backup-dir=/path/to/backups /path/to/source destination
# --backup
# --backup-dir

# others
# --size-only Compare size only.
# --ignore-times File is always copied. This does not mean that modification timestamp is not compared, but that the other items are compared even if the modification timestamp is consistent.
# --checksum The checksum is only computed if size matches. Comparison without timestamp