Continuously synchronize directories from a client to a server with emphasis on low latency (not on large files).

Permissions and timestamps are also copied, so rsync -avn --delete /source /target should always result in "nothing to do" (except during synchronization).

Uses inotify to monitor directories for changes, librsync to reduce bandwidth usage and zeromq (+ssh) for the transport.

Development is done using Python 2.7 and ZeroMQ 4.0. It may or may not run with other versions. Latest source code can be found on Github.

A shell script is provided for easy installation. Currently only Debian and UCS are supported. Please send me patches to include instructions for your distribution.

$ wget https://raw.githubusercontent.com/dansan/zrsync/master/zrsync_install
$ bash zrsync_install

This will

• install required packages supported by the Linux distribution
• download the zrsync code from github to ~/.zrsync/zrsync
• create a Python virtual environment in ~/.zrsync/virtenv
• install remaining requirements into the virtual environment
• create shortcuts for running the client and server in ~/bin

(on target system) $ ~/bin/zrsyncd
(on source system) $ ~/bin/zrsync host /my/local/dir /remote/dir

The order in which client and server are started does not matter.

Continuously sync ~/Documents to /tmp/mydocs on the same system. Zrsyncd must already be running:

$ ~/bin/zrsync localhost ~/Documents /tmp/mydocs

Continuously sync ~/Documents to ~/Documents of user foo on my.ser.ver using a SSH tunnel:

$ ~/bin/zrsync foo@my.ser.ver ~/Documents Documents

The same, but it will try to start zrsyncd on my.ser.ver, if it is not yet running and install it if is not already installed. When the client quits, it will shut down zrsyncd on the target system:

$ ~/bin/zrsync -a foo@my.ser.ver ~/Documents Documents

Sync ~/Documents to ~/Documents of user foo on my.ser.ver using a SSH tunnel once and then stop zrsync client and server. This is what rsync does:

$ ~/bin/zrsync -it foo@my.ser.ver ~/Documents Documents

Continuously sync three directories, logging in as user foo on my.ser.ver using a SSH: ~/Documents to ~/Documents, /etc to /tmp/etc and ~/git to /tmp/stuff.

$ ~/bin/zrsync foo@my.ser.ver ~/Documents Documents /etc /tmp/etc ~/git /tmp/stuff

See --help for more options:

$ ~/bin/zrsync -h
zrsync client: continuously synchronize a local directory to a [remote] directory.

Usage:
  zrsync [-ahilnstqvp PORT] <server> <source-dir> <target-dir> [<source-dir> <target-dir>]...

Arguments:
  server      server to sync to: [user@]server[:port]
              ('user@' and ':port' automatically enable --ssh)
  source-dir  local directory to sync from
  target      directory on the server to sync to
              (not starting with '/' means relative to home of user running zrsyncd)

Options:
  -a --auto              enable -lrt (--install, --start and --shutdown)
  -h --help              show this help message and exit
  -i --initial-only      quit after the initial sync
  -l --install           try to install zrsync on target (implies --ssh)
  -n --no-delete         do not delete any files or diretories on the target
  -p PORT --port=PORT    zrsyncd (not ssh) port to connect to [default: 24240]
  -r --start             start server (zrsyncd) on target if not already running (implies --ssh)
  -q --quiet             print only errors
  -s --ssh               tunnel connection through SSH.
  -t --shutdown          shutdown server when finished
  -v --verbose           print debug statements
  --version              show version and exit

$ ~/bin/zrsyncd -h
zrsync server: receive continuous updates for local directories from zrsync.

Usage:
  zrsyncd.py [-hqv] [-i IP | --ip=IP] [-p PORT | --port=PORT]

Options:
  -h --help              show this help message and exit
  -i IP --ip=IP          IP to listen on [default: *]
  -p PORT --port=PORT    port to listen on [default: 24240]
  -q --quiet             print only errors
  -v --verbose           print debug statements
  --version              show version and exit

This software is licensed under the terms of the GNU General Public License v3, see LICENSE.

• ZeroMQ is licensed under the terms of the GNU Lesser General Public License v3.
• PyZMQ is licensed under the terms of the Modified BSD License as well as the GNU Lesser General Public License v3.
• librsync is licensed under the terms of the GNU Lesser General Public License v2.1.
• python-librsync is licensed under the terms of the MIT license.
• docopt is licensed under the terms of the MIT license.
• pyinotify is licensed under the terms of the GNU General Public License v2.
• pexpect is licensed under the terms of the ISC LICENSE.