Can wget Recursively Download from FTP?

Yes, the wget command-line utility is fully capable of recursively downloading files and directories from an FTP server. This article provides a quick overview of how wget handles recursive FTP transfers, outlines the essential command-line flags required for the task, and highlights key security and performance configurations to optimize your downloads.

Understanding Recursive FTP Downloads with wget

By default, wget only downloads a single specified file. However, when dealing with FTP servers that contain complex nested directories, you can trigger a recursive download. In this mode, wget acts like a web crawler for the FTP file structure: it enters the initial directory, parses the file listings, downloads all available items, and then moves deeper into the subdirectories to repeat the process.

To initiate a basic recursive download from an FTP server, you use the -r (or --recursive) flag. A standard command looks like this:

wget -r ftp://username:password@ftp.example.com/directory/

Essential Flags for FTP Recursion

To gain finer control over what gets downloaded and how the local file structure is built, you can combine the recursive flag with several other options:

• -l <depth> (or --level=<depth>): Controls how many levels deep wget will traverse into the subdirectories. The default maximum depth is 5. If you want to download everything regardless of depth, use -l 0 or --level=inf.
• --no-parent (or -np): Crucial for FTP downloads. This prevents wget from escaping the initial directory you specified and wandering upward into parent directories on the server.
• -m (or --mirror): A shortcut flag that turns on recursion, sets the infinite depth limit, keeps session links alive, and preserves the server’s file timestamps locally. It is the ideal choice for backing up an entire FTP directory.

Handling Authentication and Connection Issues

FTP servers often require user credentials. You can pass these directly in the URL string or use dedicated flags to keep your command history cleaner:

wget --ftp-user="your_username" --ftp-password="your_password" -r ftp://ftp.example.com/target-folder/

If you are downloading a massive archive, network interruptions can break the process. Adding the -c (or --continue) flag ensures that if the connection drops, wget will resume downloading partially completed files from where it left off, rather than starting over from scratch.