быстрый, универсальный, удаленный (и локальный) инструмент для копирования файлов (a fast, versatile, remote (and local) file-copying tool)
GENERAL
Rsync copies files either to or from a remote host, or locally on
the current host (it does not support copying files between two
remote hosts).
There are two different ways for rsync to contact a remote
system: using a remote-shell program as the transport (such as
ssh or rsh) or contacting an rsync daemon directly via TCP. The
remote-shell transport is used whenever the source or destination
path contains a single colon (:) separator after a host
specification. Contacting an rsync daemon directly happens when
the source or destination path contains a double colon (::)
separator after a host specification, OR when an rsync:// URL is
specified (see also the "USING RSYNC-DAEMON FEATURES VIA A
REMOTE-SHELL CONNECTION" section for an exception to this latter
rule).
As a special case, if a single source arg is specified without a
destination, the files are listed in an output format similar to
"ls -l
".
As expected, if neither the source or destination path specify a
remote host, the copy occurs locally (see also the --list-only
option).
Rsync refers to the local side as the client and the remote side
as the server. Don't confuse server with an rsync daemon. A
daemon is always a server, but a server can be either a daemon or
a remote-shell spawned process.