NAME

rsync-ssl -⁠ a helper script for connecting to an ssl rsync daemon

SYNOPSIS

rsync-ssl [--type=SSL_TYPE] RSYNC_ARGS

The online version of this manpage (that includes cross-linking of topics) is available at https://download.samba.org/pub/rsync/rsync-ssl.1.

DESCRIPTION

The rsync-ssl script helps you to run an rsync copy to/from an rsync daemon that requires ssl connections.

The script requires that you specify an rsync-daemon arg in the style of either hostname:: (with 2 colons) or rsync://hostname/. The default port used for connecting is 874 (one higher than the normal 873) unless overridden in the environment. You can specify an overriding port via --port or by including it in the normal spot in the URL format, though both of those require your rsync version to be at least 3.2.0.

OPTIONS

If the first arg is a --type=SSL_TYPE option, the script will only use that particular program to open an ssl connection instead of trying to find an openssl or stunnel executable via a simple heuristic (assuming that the RSYNC_SSL_TYPE environment variable is not set as well -⁠-⁠ see below). This option must specify one of openssl or stunnel. The equal sign is required for this particular option.

All the other options are passed through to the rsync command, so consult the rsync(1) manpage for more information on how it works.

ENVIRONMENT VARIABLES

The ssl helper scripts are affected by the following environment variables:

RSYNC_SSL_TYPE

Specifies the program type that should be used to open the ssl connection. It must be one of openssl or stunnel. The --type=SSL_TYPE option overrides this, when specified.

RSYNC_SSL_PORT

If specified, the value is the port number that is used as the default when the user does not specify a port in their rsync command. When not specified, the default port number is 874. (Note that older rsync versions (prior to 3.2.0) did not communicate an overriding port number value to the helper script.)

RSYNC_SSL_CERT

If specified, the value is a filename that contains a certificate to use for the connection.

RSYNC_SSL_KEY

If specified, the value is a filename that contains a key for the provided certificate to use for the connection.

RSYNC_SSL_CA_CERT

If specified, the value is a filename that contains a certificate authority certificate that is used to validate the connection.

RSYNC_SSL_OPENSSL

Specifies the openssl executable to run when the connection type is set to openssl. If unspecified, the $PATH is searched for "openssl".

RSYNC_SSL_GNUTLS

Specifies the gnutls-cli executable to run when the connection type is set to gnutls. If unspecified, the $PATH is searched for "gnutls-cli".

RSYNC_SSL_STUNNEL

Specifies the stunnel executable to run when the connection type is set to stunnel. If unspecified, the $PATH is searched first for "stunnel4" and then for "stunnel".

EXAMPLES

rsync-ssl -aiv example.com::mod/ dest
rsync-ssl --type=openssl -aiv example.com::mod/ dest
rsync-ssl -aiv --port 9874 example.com::mod/ dest
rsync-ssl -aiv rsync://example.com:9874/mod/ dest

THE SERVER SIDE

For help setting up an SSL/TLS supporting rsync, see the instructions in rsyncd.conf.

SEE ALSO

rsync(1), rsyncd.conf(5)

CAVEATS

Note that using an stunnel connection requires at least version 4 of stunnel, which should be the case on modern systems. Also, it does not verify a connection against the CA certificate collection, so it only encrypts the connection without any cert validation unless you have specified the certificate environment options.

This script also supports a --type=gnutls option, but at the time of this release the gnutls-cli command was dropping output, making it unusable. If that bug has been fixed in your version, feel free to put gnutls into an exported RSYNC_SSL_TYPE environment variable to make its use the default.

BUGS

Please report bugs! See the web site at https://rsync.samba.org/.

VERSION

This manpage is current for version 3.3.0pre1 of rsync.

CREDITS

Rsync is distributed under the GNU General Public License. See the file COPYING for details.

A web site is available at https://rsync.samba.org/. The site includes an FAQ-O-Matic which may cover questions unanswered by this manual page.

AUTHOR

This manpage was written by Wayne Davison.

Mailing lists for support and development are available at https://lists.samba.org/.

22 May 2023