How to Fix Rsync Not Setting File Permissions Correctly when Transferring Local to Remote

Introduction

When transferring files from a local system to a remote server using Rsync, you might encounter issues with file permissions not being set correctly on the remote server. In this article, we will cover the key concepts of Rsync and provide a solution to this common problem.

What is Rsync?

Rsync is a popular open-source data synchronization and file transfer utility. It is designed to transfer and synchronize files between two locations efficiently. Rsync can be used to:

• Backup data
• Update files on a remote server
• Synchronize files between two directories

Rsync and File Permissions

By default, Rsync preserves file permissions during the transfer process. However, if the remote file's permissions are different from the local file, Rsync might not set the correct permissions on the remote file. This can lead to various issues, such as file ownership and access.

Symlinks and File Permissions

It's important to note that Rsync doesn't preserve symlinks' permissions by default. If you're transferring a directory with symlinks, you might need to use the --perms option to preserve their permissions as well.

Rsync Umask

Umask is a value that determines the default file permissions for new files and directories created during the transfer process. By default, Rsync sets the umask to 0022, which means new files will have permissions of -rw-r--r-- and new directories will have permissions of drwxr-xr-x.

Example: Rsync from Pi to NAS

Let's assume you have a local file on your Raspberry Pi (Pi) that you want to transfer to a NAS (Network-Attached Storage) server. The local file has the following permissions: rw-rw-r--. You want the remote file to have the same permissions: rw-r--r--.

Rsync Command

To transfer the file and set the correct permissions on the remote server, you can use the following Rsync command:

Here's a breakdown of the command:

• -a: Archive mode, which preserves file attributes, including permissions, symlinks, and timestamps.
• -v: Verbose mode, which displays detailed information about the transfer process.
• -z: Compresses the data during the transfer process to save bandwidth.
• --perms: Preserves file permissions on the remote server.
• --chmod: Changes the file permissions on the remote server.
• : The local file to be transferred.
• user@remote:: The remote user and path where the file will be transferred.

Modifying Rsync Umask

If you want to change the default umask value, you can use the --umask option:

Here, the umask value is set to 0002, which will result in new files having permissions of rw-r--r--.

Conclusion

In this article, we covered the basics of Rsync, the importance of file permissions during file transfers, and how to set the correct file permissions when transferring files from a local system to a remote server using Rsync. We also demonstrated how to modify the Rsync umask value to set the desired file permissions on the remote server.