Rsync Server on Ubuntu 24.04

This is a repackaged open source software product wherein additional charges apply for cloudimg support services.

rsync is the de facto standard tool for fast, efficient file synchronisation, mirroring and backup. Its delta transfer algorithm sends only the parts of files that have changed, so repeated syncs of large trees complete in a fraction of the time and bandwidth of a full copy. This image delivers rsync running in daemon mode, known as rsyncd, fully installed and configured as a hardened systemd service, so a working rsync server is answering on the network within minutes of launch and you skip hours of manual configuration and hardening.

rsync in daemon mode is driven entirely by its configuration file at /etc/rsyncd.conf. The server listens on TCP port 873 and exposes one or more named modules, each mapped to a directory on the server. Clients connect with the rsync protocol, for example rsync file rsync://user@server/module/, to push files to the server or pull files from it. This image ships one module named cloudimg whose file store lives on a dedicated data volume, so your synchronised data is kept on its own disk, separate from the operating system disk.

Application stack: the rsync daemon runs under systemd and answers the rsync protocol on TCP 873. The cloudimg module authenticates every transfer against a module user and password and chroots each transfer inside the module directory, so a client can never escape the module path. The whole server configuration lives in a single text file you can version control and reload with one command, with no database to run.

Secure by default: a naive rsync daemon exposes modules with no authentication and no isolation. This image does the opposite. The module requires a user and password on every transfer, there is no anonymous access, and every transfer is chrooted. There is no baked or shared credential: on the first boot of your instance a one shot service generates a unique module user and a long random password for that specific instance and writes them to a root owned credentials file, so no two instances share a credential and nothing is published in the image. For an even stronger transport you can run rsync over SSH instead, which the deployment guide covers.

Key capabilities: fast delta based synchronisation, mirroring and backup of large file trees; an authenticated, chrooted module served on TCP 873; a dedicated data volume for your synchronised files; a simple single file configuration you can grow with more modules; and a battle tested open source tool that underpins a large share of the world's backup and mirroring pipelines. Common uses include a central backup target for servers and workstations, a mirror or distribution point for large datasets and build artifacts, and a scheduled off host copy of important directories.

Get started: retrieve the generated module user and password from the credentials file, then push and pull files from any rsync client using the rsync protocol on port 873, or over SSH for end to end encryption. cloudimg engineers can help with module design, backup scheduling, rsync over SSH, bandwidth limits and retention after purchase.

This is a repackaged open source software product with additional charges for cloudimg support services. rsync is distributed under the GNU GPL v3. All product and company names are trademarks or registered trademarks of their respective holders. Use of them does not imply any affiliation with or endorsement by them.