Secure Copy is a UNIX standard used to transfer files from one computer to another. He's how to use the function in macOS, all via the Terminal window.

If it works, then you check rsync and Delta Copy. Are you trying to use the root login? - most setups block remote login as root, so you can't login directly as root via ssh.

Here's how to use the secure copy command, with SSH key authentication, for a more secure way to copy files to your remote Linux servers.

Apple's Remote Login feature in OS X can be used for securely transferring files using several protocols.

File transfer protocol, or FTP, is the standard command for transferring files between computer systems. The "sftp" command is a secure version of "ftp" within a SSH session.

FTP was the popular protocol for file transfer but short of using FTPS, it doesn't provide the security required these days. Here's how to use Secure Copy (SCP) for file transfer.