Using rsync

Using rsync
Learn the basics of the rsync program and how to use it effectively.

This article demonstrates how to work with rsync.

When to use rsync
Rsync allows you to synchronize directories locally or between two computers. It automatically detects which files are new or have changed and updates the destination accordingly.

This can be useful in many scenarios. For example, you can back up your website to another computer. Or, if you have a development environment on another server, you can deploy it to your ruachost.com account.

How to use rsync
Rsync has many features, but the following command-line options are enough to get started:

• The -a option enables archive mode, preserving file permissions, ownership, and modification times.

• The -e option specifies the remote shell, often set to ssh.

• The -l option preserves symbolic links.

Note
Using the -a option automatically enables symbolic link preservation.

• The -r option allows rsync to recurse through subdirectories.

Note
Using the -a option automatically enables recursion.

• The -v option enables verbose mode, showing information while rsync runs. You can omit it or use -vv for more detailed output.

• The -z option enables compression during file transfers.

Examples
Here’s how to use these options:

1. Log in to your account via SSH.

2. Ensure you are in your home directory:

cd ~

3. To back up (or "push") your public_html directory to a remote server at example.com, run:

rsync -avz -e ssh public_html user@example.com:~/backup

Note
This assumes SSH on port 22. To use a different port, include the -p option, for example:

rsync -avz -e "ssh -p7822" public_html user@example.com:~/backup

After completion, the remote server at example.com will have a backup/public_html directory identical to your local public_html directory.

Another common scenario is "pulling" files from a remote server. If you have a development environment on a remote server, you can pull files into your ruachost.com account. Each subsequent pull updates only changed files, saving time and bandwidth:

rsync -avz -e ssh user@example.com:~/public_html .

After rsync finishes, your local public_html directory contains a copy of the remote server's public_html files.

More information
This is a brief introduction to rsync. For full documentation, visit rsync documentation.