RSYNC, an open-source utility used for data synchronization and file transfer, employs a unique algorithm that reduces the amount of data sent over the network by only transferring the changes made between the source and destination files. However, RSYNC operates over SSH (Secure Shell) network protocol for data communication, not FTP (File Transfer Protocol).
RSYNC is predominantly used in local and remote file and directory synchronization between two locations within a network. For instance, RSYNC commands can be used to synchronize files and folders on a local machine to a remote machine over a network, and vice versa, and even to synchronize files from one local directory to another (Hostinger Tutorials, 2019).
On the other hand, FTP is a standard networking protocol that allows file transfer from one host to another over a network. FTP operates in a client-server architecture, where the client initiates a connection to the server to download or upload files (Paessler AG, n.d.).
It’s important to note that the underlying mechanisms of RSYNC and FTP differ fundamentally. RSYNC isn’t designed to interact with FTP servers and by default cannot directly download files from an FTP server. FTP requires explicit client-server interactions to list, retrieve, and store files, while RSYNC operates over SSH, which allows for more generalized remote command execution and file transfer.
For downloading files from an FTP server, FTP clients or command-line tools like “wget” or “curl” can be used. For instance, Wget is a free utility for non-interactive download of files from the web, which supports protocols like FTP and HTTP and retrieval through HTTP proxies (GNU, 2020). Similarly, Curl supports a wide variety of protocols including HTTP, HTTPS, FTP, and more (Curl, n.d.).
However, there is a way to use RSYNC for FTP servers by mounting the FTP server as a local filesystem using curlftpfs. Curlftpfs is a tool that connects the libcurl library with FUSE (Filesystem in Userspace). With curlftpfs, users can mount an FTP server as a local directory and then use all basic Linux commands, including RSYNC (Ubuntu Manpage, n.d.).
In conclusion, while RSYNC can’t natively download files from an FTP server, workaround solutions like curlftpfs exist to use RSYNC and FTP together. However, for direct interactions with FTP servers, you might want to consider FTP-specific tools or utilities like Wget or Curl.
Sources:
- Hostinger Tutorials (2019): https://www.hostinger.com/tutorials/rsync-command-linux
- Paessler AG, What is FTP?: https://www.paessler.com/it-explained/ftp
- GNU, Wget: https://www.gnu.org/software/wget/
- Curl: https://curl.se/doc/
- Ubuntu Manpage, curlftpfs: http://manpages.ubuntu.com/manpages/focal/man1/curlftpfs.1.html
