Introduction to rsync
The rsync package contains the
rsync utility. This
is useful for synchronizing large file archives over a network.
![[Note]](../images/note.png)
Note
Development versions of BLFS may not build or run some packages
properly if LFS or dependencies have been updated since the most
recent stable versions of the books.
Package Information
-
Download (HTTP): https://www.samba.org/ftp/rsync/src/rsync-3.3.0.tar.gz
-
Download MD5 sum: f5c17f9c9164ef9e60d9d8c96b23da06
-
Download size: 1.2 MB
-
Estimated disk space required: 9.2 MB (with tests; add 24 MB
for HTML API documentation)
-
Estimated build time: 0.7 SBU (with tests)
rsync Dependencies
Recommended
popt-1.19
Optional
Doxygen-1.12.0 and xxhash
Installation of rsync
For security reasons, running the rsync server as an unprivileged user and group
is encouraged. If you intend to run rsync as a daemon, create the
rsyncd user and group with the
following commands issued by the root user:
groupadd -g 48 rsyncd &&
useradd -c "rsyncd Daemon" -m -d /home/rsync -g rsyncd \
-s /bin/false -u 48 rsyncd
Install rsync by running the
following commands:
./configure --prefix=/usr \
--disable-xxhash \
--without-included-zlib &&
make
If you have Doxygen-1.12.0 installed and wish to build
HTML API documentation, issue:
doxygen
To test the results, issue: make
check.
Now, as the root user:
make install
If you built the documentation, install it using the following
commands as the root user:
install -v -m755 -d /usr/share/doc/rsync-3.3.0/api &&
install -v -m644 dox/html/* /usr/share/doc/rsync-3.3.0/api
Command Explanations
--disable-xxhash: This
switch disables advanced xxhash checksum support. Remove this
switch if you have installed xxhash.
--without-included-zlib:
This switch enables compilation with the system-installed zlib
library.
Configuring rsync
Config Files
/etc/rsyncd.conf
Configuration Information
For client access to remote files, you may need to install the
OpenSSH-9.9p1 package to connect to the
remote server.
This is a simple download-only configuration to set up running
rsync as a server.
See the rsyncd.conf(5)
man-page for additional options (i.e., user authentication).
cat > /etc/rsyncd.conf << "EOF"
# This is a basic rsync configuration file
# It exports a single module without user authentication.
motd file = /home/rsync/welcome.msg
use chroot = yes
[localhost]
path = /home/rsync
comment = Default rsync module
read only = yes
list = yes
uid = rsyncd
gid = rsyncd
EOF
You can find additional configuration information and general
documentation about rsync at https://rsync.samba.org/documentation.html.
Systemd Unit
Note that you only need to start the rsync server if you want to provide an
rsync archive on your local
machine. You don't need this unit to
run the rsync client.
Install the rsyncd.service unit included in the
blfs-systemd-units-20240916 package.
make install-rsyncd
Note
This package comes with two types of units: A service file and
a socket file. The service file will start rsync daemon once at
boot and it will keep running until the system shuts down. The
socket file will make systemd listen on rsync port (Default
873, needs to be edited for anything else) and will start rsync
daemon when something tries to connect to that port and stop
the daemon when the connection is terminated. This is called
socket activation and is analogous to using {,x}inetd on a SysVinit based system.
By default, the first method is used - rsync daemon is started
at boot and stopped at shutdown. If the socket method is
desired, you need to run as the root user:
systemctl stop rsyncd &&
systemctl disable rsyncd &&
systemctl enable rsyncd.socket &&
systemctl start rsyncd.socket
Note that socket method is only useful for remote backups. For
local backups you'll need the service method.