rsyncd.conf(5)rsyncd.conf(5)NAMErsyncd.conf - configuration file for rsync server
SYNOPSISrsyncd.confDESCRIPTION
The rsyncd.conf file is the runtime configuration file for
rsync when run as an rsync server.
The rsyncd.conf file controls authentication, access, log-
ging and available modules.
FILE FORMAT
The file consists of modules and parameters. A module
begins with the name of the module in square brackets and
continues until the next module begins. Modules contain
parameters of the form 'name = value'.
The file is line-based - that is, each newline-terminated
line represents either a comment, a module name or a
parameter.
Only the first equals sign in a parameter is significant.
Whitespace before or after the first equals sign is dis-
carded. Leading, trailing and internal whitespace in mod-
ule and parameter names is irrelevant. Leading and trail-
ing whitespace in a parameter value is discarded. Internal
whitespace within a parameter value is retained verbatim.
Any line beginning with a hash (#) is ignored, as are
lines containing only whitespace.
Any line ending in a \ is "continued" on the next line in
the customary UNIX fashion.
The values following the equals sign in parameters are all
either a string (no quotes needed) or a boolean, which may
be given as yes/no, 0/1 or true/false. Case is not signif-
icant in boolean values, but is preserved in string val-
ues.
LAUNCHING THE RSYNC DAEMON
The rsync daemon is launched by specifying the --daemon
option to rsync.
The daemon must run with root privileges if you wish to
use chroot, to bind to a port numbered under 1024 (as is
the default 873), or to set file ownership. Otherwise, it
must just have permission to read and write the appropri-
ate data, log, and lock files.
You can launch it either via inetd, as a stand-alone dae-
mon, or from an rsync client via a remote shell. If run
as a stand-alone daemon then just run the command "rsync
--daemon" from a suitable startup script. If run from an
rsync client via a remote shell (by specifying both the
"-e/--rsh" option and server mode with "::" or
"rsync://"), the --daemon option is automatically passed
to the remote side.
When run via inetd you should add a line like this to
/etc/services:
rsync 873/tcp
and a single line something like this to /etc/inetd.conf:
rsync stream tcp nowait root
/usr/bin/rsync rsyncd --daemon
Replace "/usr/bin/rsync" with the path to where you have
rsync installed on your system. You will then need to
send inetd a HUP signal to tell it to reread its config
file.
Note that you should not send the rsync server a HUP sig-
nal to force it to reread the rsyncd.conf file. The file
is re-read on each client connection.
GLOBAL OPTIONS
The first parameters in the file (before a [module]
header) are the global parameters.
You may also include any module parameters in the global
part of the config file in which case the supplied value
will override the default for that parameter.
motd file
The "motd file" option allows you to specify a
"message of the day" to display to clients on each
connect. This usually contains site information and
any legal notices. The default is no motd file.
log file
The "log file" option tells the rsync daemon to log
messages to that file rather than using syslog.
This is particularly useful on systems (such as
AIX) where syslog() doesn't work for chrooted pro-
grams.
pid file
The "pid file" option tells the rsync daemon to
write its process id to that file.
syslog facility
The "syslog facility" option allows you to specify
the syslog facility name to use when logging mes-
sages from the rsync server. You may use any stan-
dard syslog facility name which is defined on your
system. Common names are auth, authpriv, cron, dae-
mon, ftp, kern, lpr, mail, news, security, syslog,
user, uucp, local0, local1, local2, local3, local4,
local5, local6 and local7. The default is daemon.
socket options
This option can provide endless fun for people who
like to tune their systems to the utmost degree.
You can set all sorts of socket options which may
make transfers faster (or slower!). Read the man
page for the setsockopt() system call for details
on some of the options you may be able to set. By
default no special socket options are set.
MODULE OPTIONS
After the global options you should define a number of
modules, each module exports a directory tree as a sym-
bolic name. Modules are exported by specifying a module
name in square brackets [module] followed by the options
for that module.
comment
The "comment" option specifies a description string
that is displayed next to the module name when
clients obtain a list of available modules. The
default is no comment.
path The "path" option specifies the directory in the
servers filesystem to make available in this mod-
ule. You must specify this option for each module
in rsyncd.conf.
use chroot
If "use chroot" is true, the rsync server will
chroot to the "path" before starting the file
transfer with the client. This has the advantage
of extra protection against possible implementation
security holes, but it has the disadvantages of
requiring super-user privileges, of not being able
to follow symbolic links outside of the new root
path when reading, and of implying the --numeric-
ids option because /etc/passwd becomes inaccessi-
ble. When "use chroot" is false, for security rea-
sons symlinks may only be relative paths pointing
to other files within the root path, and leading
slashes are removed from absolute paths. The
default for "use chroot" is true.
max connections
The "max connections" option allows you to specify
the maximum number of simultaneous connections you
will allow. Any clients connecting when the maxi-
mum has been reached will receive a message telling
them to try later. The default is 0 which means no
limit. See also the "lock file" option.
lock file
The "lock file" option specifies the file to use to
support the "max connections" option. The rsync
server uses record locking on this file to ensure
that the max connections limit is not exceeded for
the modules sharing the lock file. The default is
/var/run/rsyncd.lock.
read only
The "read only" option determines whether clients
will be able to upload files or not. If "read only"
is true then any attempted uploads will fail. If
"read only" is false then uploads will be possible
if file permissions on the server allow them. The
default is for all modules to be read only.
list The "list" option determines if this module should
be listed when the client asks for a listing of
available modules. By setting this to false you can
create hidden modules. The default is for modules
to be listable.
uid The "uid" option specifies the user name or user id
that file transfers to and from that module should
take place as when the daemon was run as root. In
combination with the "gid" option this determines
what file permissions are available. The default is
uid -2, which is normally the user "nobody".
gid The "gid" option specifies the group name or group
id that file transfers to and from that module
should take place as when the daemon was run as
root. This complements the "uid" option. The
default is gid -2, which is normally the group
"nobody".
exclude
The "exclude" option allows you to specify a space
separated list of patterns to add to the exclude
list. This is equivalent to the client specifying
these patterns with the --exclude option, except
that the exclude list is not passed to the client
and thus only applies on the server: that is, it
excludes files received by a client when receiving
from a server and files deleted on a server when
sending to a server, but it doesn't exclude files
sent from a client when sending to a server or
files deleted on a client when receiving from a
server. Only one "exclude" option may be speci-
fied, but you can use "-" and "+" before patterns
to specify exclude/include.
Note that this option is not designed with strong
security in mind, it is quite possible that a
client may find a way to bypass this exclude list.
If you want to absolutely ensure that certain files
cannot be accessed then use the uid/gid options in
combination with file permissions.
exclude from
The "exclude from" option specifies a filename on
the server that contains exclude patterns, one per
line. This is equivalent to the client specifying
the --exclude-from option with a equivalent file
except that it applies only on the server. See
also the "exclude" option above.
include
The "include" option allows you to specify a space
separated list of patterns which rsync should not
exclude. This is equivalent to the client specify-
ing these patterns with the --include option except
that it applies only on the server. This is useful
as it allows you to build up quite complex
exclude/include rules. Only one "include" option
may be specified, but you can use "+" and "-"
before patterns to switch include/exclude. See
also the "exclude" option above.
include from
The "include from" option specifies a filename on
the server that contains include patterns, one per
line. This is equivalent to the client specifying
the --include-from option with a equivalent file
except that it applies only on the server. See
also the "exclude" option above.
auth users
The "auth users" option specifies a comma and space
separated list of usernames that will be allowed to
connect to this module. The usernames do not need
to exist on the local system. The usernames may
also contain shell wildcard characters. If "auth
users" is set then the client will be challenged to
supply a username and password to connect to the
module. A challenge response authentication proto-
col is used for this exchange. The plain text user-
names are passwords are stored in the file speci-
fied by the "secrets file" option. The default is
for all users to be able to connect without a pass-
word (this is called "anonymous rsync").
See also the CONNECTING TO AN RSYNC SERVER OVER A
REMOTE SHELL PROGRAM section in rsync(1) for infor-
mation on how handle an rsyncd.conf-level username
that differs from the remote-shell-level username
when using a remote shell to connect to a rsync
server.
secrets file
The "secrets file" option specifies the name of a
file that contains the username:password pairs used
for authenticating this module. This file is only
consulted if the "auth users" option is specified.
The file is line based and contains username:pass-
word pairs separated by a single colon. Any line
starting with a hash (#) is considered a comment
and is skipped. The passwords can contain any char-
acters but be warned that many operating systems
limit the length of passwords that can be typed at
the client end, so you may find that passwords
longer than 8 characters don't work.
There is no default for the "secrets file" option,
you must choose a name (such as
/etc/rsyncd.secrets). The file must normally not
be readable by "other"; see "strict modes".
strict modes
The "strict modes" option determines whether or not
the permissions on the secrets file will be
checked. If "strict modes" is true, then the
secrets file must not be readable by any user id
other than the one that the rsync daemon is running
under. If "strict modes" is false, the check is
not performed. The default is true. This option
was added to accommodate rsync running on the Win-
dows operating system.
hosts allow
The "hosts allow" option allows you to specify a
list of patterns that are matched against a con-
necting clients hostname and IP address. If none of
the patterns match then the connection is rejected.
Each pattern can be in one of five forms:
o a dotted decimal IPv4 address of the form a.b.c.d,
or an IPv6 address of the form a:b:c::d:e:f. In
this case the incoming machine's IP address must
match exactly.
o an address/mask in the form ipaddr/n where ipaddr
is the IP address and n is the number of one bits
in the netmask. All IP addresses which match the
masked IP address will be allowed in.
o an address/mask in the form ipaddr/maskaddr where
ipaddr is the IP address and maskaddr is the net-
mask in dotted decimal notation for IPv4, or simi-
lar for IPv6, e.g. ffff:ffff:ffff:ffff:: instead of
/64. All IP addresses which match the masked IP
address will be allowed in.
o a hostname. The hostname as determined by a reverse
lookup will be matched (case insensitive) against
the pattern. Only an exact match is allowed in.
o a hostname pattern using wildcards. These are
matched using the same rules as normal unix file-
name matching. If the pattern matches then the
client is allowed in.
Note IPv6 link-local addresses can have a scope in
the address specification:
fe80::1%link1
fe80::%link1/64
fe80::%link1/ffff:ffff:ffff:ffff::
You can also combine "hosts allow" with a separate
"hosts deny" option. If both options are specified
then the "hosts allow" option s checked first and a
match results in the client being able to connect.
The "hosts deny" option is then checked and a match
means that the host is rejected. If the host does
not match either the "hosts allow" or the "hosts
deny" patterns then it is allowed to connect.
The default is no "hosts allow" option, which means
all hosts can connect.
hosts deny
The "hosts deny" option allows you to specify a
list of patterns that are matched against a con-
necting clients hostname and IP address. If the
pattern matches then the connection is rejected.
See the "hosts allow" option for more information.
The default is no "hosts deny" option, which means
all hosts can connect.
ignore errors
The "ignore errors" option tells rsyncd to ignore
IO errors on the server when deciding whether to
run the delete phase of the transfer. Normally
rsync skips the --delete step if any IO errors have
occurred in order to prevent disasterous deletion
due to a temporary resource shortage or other IO
error. In some cases this test is counter produc-
tive so you can use this option to turn off this
behaviour.
ignore nonreadable
This tells the rsync server to completely ignore
files that are not readable by the user. This is
useful for public archives that may have some non-
readable files among the directories, and the
sysadmin doesn't want those files to be seen at
all.
transfer logging
The "transfer logging" option enables per-file log-
ging of downloads and uploads in a format somewhat
similar to that used by ftp daemons. If you want to
customize the log formats look at the log format
option.
log format
The "log format" option allows you to specify the
format used for logging file transfers when trans-
fer logging is enabled. The format is a text string
containing embedded single character escape
sequences prefixed with a percent (%) character.
The prefixes that are understood are:
o %h for the remote host name
o %a for the remote IP address
o %l for the length of the file in bytes
o %p for the process id of this rsync session
o %o for the operation, which is either "send" or
"recv"
o %f for the filename
o %P for the module path
o %m for the module name
o %t for the current date time
o %u for the authenticated username (or the null
string)
o %b for the number of bytes actually transferred
o %c when sending files this gives the number of
checksum bytes received for this file
The default log format is "%o %h [%a] %m (%u) %f
%l", and a "%t [%p] " is always added to the begin-
ning when using the "log file" option.
A perl script called rsyncstats to summarize this
format is included in the rsync source code distri-
bution.
timeout
The "timeout" option allows you to override the
clients choice for IO timeout for this module.
Using this option you can ensure that rsync won't
wait on a dead client forever. The timeout is spec-
ified in seconds. A value of zero means no timeout
and is the default. A good choice for anonymous
rsync servers may be 600 (giving a 10 minute time-
out).
refuse options
The "refuse options" option allows you to specify a
space separated list of rsync command line options
that will be refused by your rsync server. The
full names of the options must be used (i.e., you
must use "checksum" not "c" to disable checksum-
ming). When an option is refused, the server
prints an error message and exits. To prevent all
compression, you can use "dont compress = *" (see
below) instead of "refuse options = compress" to
avoid returning an error to a client that requests
compression.
dont compress
The "dont compress" option allows you to select
filenames based on wildcard patterns that should
not be compressed during transfer. Compression is
expensive in terms of CPU usage so it is usually
good to not try to compress files that won't com-
press well, such as already compressed files.
The "dont compress" option takes a space separated
list of case-insensitive wildcard patterns. Any
source filename matching one of the patterns will
not be compressed during transfer.
The default setting is
*.gz *.tgz *.zip *.z *.rpm *.deb *.iso *.bz2 *.tbz
AUTHENTICATION STRENGTH
The authentication protocol used in rsync is a 128 bit MD4
based challenge response system. Although I believe that
no one has ever demonstrated a brute-force break of this
sort of system you should realize that this is not a "mil-
itary strength" authentication system. It should be good
enough for most purposes but if you want really top qual-
ity security then I recommend that you run rsync over ssh.
Also note that the rsync server protocol does not cur-
rently provide any encryption of the data that is trans-
ferred over the link. Only authentication is provided. Use
ssh as the transport if you want encryption.
Future versions of rsync may support SSL for better
authentication and encryption, but that is still being
investigated.
EXAMPLES
A simple rsyncd.conf file that allow anonymous rsync to a
ftp area at /home/ftp would be:
[ftp]
path = /home/ftp
comment = ftp export area
A more sophisticated example would be:
uid = nobody
gid = nobody
use chroot = no
max connections = 4
syslog facility = local5
pid file = /var/run/rsyncd.pid
[ftp]
path = /var/ftp/pub
comment = whole ftp area (approx 6.1 GB)
[sambaftp]
path = /var/ftp/pub/samba
comment = Samba ftp area (approx 300 MB)
[rsyncftp]
path = /var/ftp/pub/rsync
comment = rsync ftp area (approx 6 MB)
[sambawww]
path = /public_html/samba
comment = Samba WWW pages (approx 240 MB)
[cvs]
path = /data/cvs
comment = CVS repository (requires authentication)
auth users = tridge, susan
secrets file = /etc/rsyncd.secrets
The /etc/rsyncd.secrets file would look something like
this:
tridge:mypass
susan:herpass
FILES
/etc/rsyncd.conf or rsyncd.confSEE ALSOrsync(1)DIAGNOSTICSBUGS
The rsync server does not send all types of error messages
to the client. this means a client may be mystified as to
why a transfer failed. The error will have been logged by
syslog on the server.
Please report bugs! The rsync bug tracking system is
online at http://rsync.samba.org/
VERSION
This man page is current for version 2.0 of rsync
CREDITS
rsync is distributed under the GNU public license. See
the file COPYING for details.
The primary ftp site for rsync is
ftp://rsync.samba.org/pub/rsync.
A WEB site is available at http://rsync.samba.org/
We would be delighted to hear from you if you like this
program.
This program uses the zlib compression library written by
Jean-loup Gailly and Mark Adler.
THANKS
Thanks to Warren Stanley for his original idea and patch
for the rsync server. Thanks to Karsten Thygesen for his
many suggestions and documentation!
AUTHOR
rsync was written by Andrew Tridgell and Paul Mackerras.
They may be contacted via email at tridge@samba.org and
Paul.Mackerras@cs.anu.edu.au
26 Jan 2003 rsyncd.conf(5)
