rsyncd.conf - configuration file for rsync in daemon mode
The rsyncd.conf file is the runtime configuration file for rsync when run as an
The rsyncd.conf file controls authentication, access, logging and available
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 discarded. Leading, trailing and internal
whitespace in module and parameter names is irrelevant. Leading and trailing
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. (If a hash occurs after anything other than leading
whitespace, it is considered a part of the line’s content.)
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 significant in boolean values, but is preserved in string values.
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 appropriate
data, log, and lock files.
You can launch it either via inetd, as a stand-alone daemon, 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.
When run via inetd you should add a line like this to /etc/services:
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 daemon a HUP signal to force it
to reread the rsyncd.conf file. The file is re-read on each client connection.
The first parameters in the file (before a [module] header) are the global
parameters. Rsync also allows for the use of a "[global]" module
name to indicate the start of one or more global-parameter sections (the name
must be lower case).
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.
You may use references to environment variables in the values of parameters.
String parameters will have %VAR% references expanded as late as possible
(when the string is used in the program), allowing for the use of variables
that rsync sets at connection time, such as RSYNC_USER_NAME. Non-string
parameters (such as true/false settings) are expanded when read from the
config file. If a variable does not exist in the environment, or if a sequence
of characters is not a valid reference (such as an un-paired percent sign),
the raw characters are passed through unchanged. This helps with backward
compatibility and safety (e.g. expanding a non-existent %VAR% to an empty
string in a path could result in a very unsafe path). The safest way to insert
a literal % into a value is to use %%.
- motd file
- This parameter 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. This
can be overridden by the --dparam=motdfile=FILE command-line option
when starting the daemon.
- pid file
- This parameter tells the rsync daemon to write its process
ID to that file. If the file already exists, the rsync daemon will abort
rather than overwrite the file. This can be overridden by the
--dparam=pidfile=FILE command-line option when starting the
- You can override the default port the daemon will listen on
by specifying this value (defaults to 873). This is ignored if the daemon
is being run by inetd, and is superseded by the --port command-line
- You can override the default IP address the daemon will
listen on by specifying this value. This is ignored if the daemon is being
run by inetd, and is superseded by the --address command-line
- socket options
- This parameter 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.
These settings can also be specified via the --sockopts
- listen backlog
- You can override the default backlog value when the daemon
listens for connections. It defaults to 5.
After the global parameters you should define a number of modules, each module
exports a directory tree as a symbolic name. Modules are exported by
specifying a module name in square brackets [module] followed by the
parameters for that module. The module name cannot contain a slash or a
closing square bracket. If the name contains whitespace, each internal
sequence of whitespace will be changed into a single space, while leading or
trailing whitespace will be discarded. Also, the name cannot be
"global" as that exact name indicates that global parameters follow
As with GLOBAL PARAMETERS, you may use references to environment variables in
the values of parameters. See the GLOBAL PARAMETERS section for more details.
- This parameter 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.
- This parameter specifies the directory in the
daemon’s filesystem to make available in this module. You must
specify this parameter for each module in rsyncd.conf.
- You may base the path’s value off of an environment
variable by surrounding the variable name with percent signs. You can even
reference a variable that is set by rsync when the user connects. For
example, this would use the authorizing user’s name in the
path = /home/%RSYNC_USER_NAME%
- It is fine if the path includes internal spaces -- they
will be retained verbatim (which means that you shouldn’t try to
escape them). If your final directory has a trailing space (and this is
somehow not something you wish to fix), append a trailing slash to the
path to avoid losing the trailing whitespace.
- use chroot
- If "use chroot" is true, the rsync daemon 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 that are
either absolute or outside of the new root path, and of complicating the
preservation of users and groups by name (see below).
- As an additional safety feature, you can specify a dot-dir
in the module’s "path" to indicate the point where the
chroot should occur. This allows rsync to run in a chroot with a
non-"/" path for the top of the transfer hierarchy. Doing this
guards against unintended library loading (since those absolute paths will
not be inside the transfer hierarchy unless you have used an unwise
pathname), and lets you setup libraries for the chroot that are outside of
the transfer. For example, specifying "/var/rsync/./module1"
will chroot to the "/var/rsync" directory and set the
inside-chroot path to "/module1". If you had omitted the
dot-dir, the chroot would have used the whole path, and the inside-chroot
path would have been "/".
- When "use chroot" is false or the inside-chroot
path is not "/", rsync will: (1) munge symlinks by default for
security reasons (see "munge symlinks" for a way to turn this
off, but only if you trust your users), (2) substitute leading slashes in
absolute paths with the module’s path (so that options such as
--backup-dir, --compare-dest, etc. interpret an absolute
path as rooted in the module’s "path" dir), and (3) trim
".." path elements from args if rsync believes they would escape
the module hierarchy. The default for "use chroot" is true, and
is the safer choice (especially if the module is not read-only).
- When this parameter is enabled, the "numeric-ids"
option will also default to being enabled (disabling name lookups). See
below for what a chroot needs in order for name lookups to succeed.
- If you copy library resources into the module’s
chroot area, you should protect them through your OS’s normal
user/group or ACL settings (to prevent the rsync module’s user from
being able to change them), and then hide them from the user’s view
via "exclude" (see how in the discussion of that parameter). At
that point it will be safe to enable the mapping of users and groups by
name using this "numeric ids" daemon parameter.
- Note also that you are free to setup custom user/group
information in the chroot area that is different from your normal system.
For example, you could abbreviate the list of users and groups.
- numeric ids
- Enabling this parameter disables the mapping of users and
groups by name for the current daemon module. This prevents the daemon
from trying to load any user/group-related files or libraries. This
enabling makes the transfer behave as if the client had passed the
--numeric-ids command-line option. By default, this parameter is
enabled for chroot modules and disabled for non-chroot modules. Also keep
in mind that uid/gid preservation requires the module to be running as
root (see "uid") or for "fake super" to be
- A chroot-enabled module should not have this parameter
enabled unless you’ve taken steps to ensure that the module has the
necessary resources it needs to translate names, and that it is not
possible for a user to change those resources. That includes being the
code being able to call functions like getpwuid() , getgrgid() ,
getpwname() , and getgrnam() ). You should test what libraries and config
files are required for your OS and get those setup before starting to test
name mapping in rsync.
- munge symlinks
- This parameter tells rsync to modify all symlinks in the
same way as the (non-daemon-affecting) --munge-links command-line
option (using a method described below). This should help protect your
files from user trickery when your daemon module is writable. The default
is disabled when "use chroot" is on and the inside-chroot path
is "/", otherwise it is enabled.
- If you disable this parameter on a daemon that is not
read-only, there are tricks that a user can play with uploaded symlinks to
access daemon-excluded items (if your module has any), and, if "use
chroot" is off, rsync can even be tricked into showing or changing
data that is outside the module’s path (as access-permissions
- The way rsync disables the use of symlinks is to prefix
each one with the string "/rsyncd-munged/". This prevents the
links from being used as long as that directory does not exist. When this
parameter is enabled, rsync will refuse to run if that path is a directory
or a symlink to a directory. When using the "munge symlinks"
parameter in a chroot area that has an inside-chroot path of
"/", you should add "/rsyncd-munged/" to the exclude
setting for the module so that a user can’t try to create it.
- Note: rsync makes no attempt to verify that any
pre-existing symlinks in the module’s hierarchy are as safe as you
want them to be (unless, of course, it just copied in the whole
hierarchy). If you setup an rsync daemon on a new area or locally add
symlinks, you can manually protect your symlinks from being abused by
prefixing "/rsyncd-munged/" to the start of every
symlink’s value. There is a perl script in the support directory of
the source code named "munge-symlinks" that can be used to add
or remove this prefix from your symlinks.
- When this parameter is disabled on a writable module and
"use chroot" is off (or the inside-chroot path is not
"/"), incoming symlinks will be modified to drop a leading slash
and to remove ".." path elements that rsync believes will allow
a symlink to escape the module’s hierarchy. There are tricky ways
to work around this, though, so you had better trust your users if you
choose this combination of parameters.
- This specifies the name of the character set in which the
module’s filenames are stored. If the client uses an --iconv
option, the daemon will use the value of the "charset" parameter
regardless of the character set the client actually passed. This allows
the daemon to support charset conversion in a chroot module without extra
files in the chroot area, and also ensures that name-translation is done
in a consistent manner. If the "charset" parameter is not set,
the --iconv option is refused, just as if "iconv" had
been specified via "refuse options".
- If you wish to force users to always use --iconv for
a particular module, add "no-iconv" to the "refuse
options" parameter. Keep in mind that this will restrict access to
your module to very new rsync clients.
- max connections
- This parameter allows you to specify the maximum number of
simultaneous connections you will allow. Any clients connecting when the
maximum has been reached will receive a message telling them to try later.
The default is 0, which means no limit. A negative value disables the
module. See also the "lock file" parameter.
- log file
- When the "log file" parameter is set to a
non-empty string, the rsync daemon will log messages to the indicated file
rather than using syslog. This is particularly useful on systems (such as
AIX) where syslog() doesn’t work for chrooted programs. The file is
opened before chroot() is called, allowing it to be placed outside the
transfer. If this value is set on a per-module basis instead of globally,
the global log will still contain any authorization failures or
config-file error messages.
- If the daemon fails to open the specified file, it will
fall back to using syslog and output an error about the failure. (Note
that the failure to open the specified log file used to be a fatal
- This setting can be overridden by using the
--log-file=FILE or --dparam=logfile=FILE command-line
options. The former overrides all the log-file parameters of the daemon
and all module settings. The latter sets the daemon’s log file and
the default for all the modules, which still allows modules to override
the default setting.
- syslog facility
- This parameter allows you to specify the syslog facility
name to use when logging messages from the rsync daemon. You may use any
standard syslog facility name which is defined on your system. Common
names are auth, authpriv, cron, daemon, ftp, kern, lpr, mail, news,
security, syslog, user, uucp, local0, local1, local2, local3, local4,
local5, local6 and local7. The default is daemon. This setting has no
effect if the "log file" setting is a non-empty string (either
set in the per-modules settings, or inherited from the global
- max verbosity
- This parameter allows you to control the maximum amount of
verbose information that you’ll allow the daemon to generate (since
the information goes into the log file). The default is 1, which allows
the client to request one level of verbosity.
- This also affects the user’s ability to request
higher levels of --info and --debug logging. If the max
value is 2, then no info and/or debug value that is higher than what would
be set by -vv will be honored by the daemon in its logging. To see
how high of a verbosity level you need to accept for a particular
info/debug level, refer to "rsync --info=help" and "rsync
--debug=help". For instance, it takes max-verbosity 4 to be able to
output debug TIME2 and FLIST3.
- lock file
- This parameter specifies the file to use to support the
"max connections" parameter. The rsync daemon 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
- read only
- This parameter 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 daemon side allow them. The default is
for all modules to be read only.
- Note that "auth users" can override this setting
on a per-user basis.
- write only
- This parameter determines whether clients will be able to
download files or not. If "write only" is true then any
attempted downloads will fail. If "write only" is false then
downloads will be possible if file permissions on the daemon side allow
them. The default is for this parameter to be disabled.
- This parameter determines whether this module is listed
when the client asks for a listing of available modules. In addition, if
this is false, the daemon will pretend the module does not exist when a
client denied by "hosts allow" or "hosts deny"
attempts to access it. Realize that if "reverse lookup" is
disabled globally but enabled for the module, the resulting reverse lookup
to a potentially client-controlled DNS server may still reveal to the
client that it hit an existing module. The default is for modules to be
- This parameter 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" parameter this
determines what file permissions are available. The default when run by a
super-user is to switch to the system’s "nobody" user.
The default for a non-super-user is to not try to change the user. See
also the "gid" parameter.
- The RSYNC_USER_NAME environment variable may be used to
request that rsync run as the authorizing user. For example, if you want a
rsync to run as the same user that was received for the rsync
authentication, this setup is useful:
uid = %RSYNC_USER_NAME%
gid = *
- This parameter specifies one or more group names/IDs that
will be used when accessing the module. The first one will be the default
group, and any extra ones be set as supplemental groups. You may also
specify a "*" as the first gid in the list, which will be
replaced by all the normal groups for the transfer’s user (see
"uid"). The default when run by a super-user is to switch to
your OS’s "nobody" (or perhaps "nogroup") group
with no other supplementary groups. The default for a non-super-user is to
not change any group attributes (and indeed, your OS may not allow a
non-super-user to try to change their group settings).
- fake super
- Setting "fake super = yes" for a module causes
the daemon side to behave as if the --fake-super command-line
option had been specified. This allows the full attributes of a file to be
stored without having to have the daemon actually running as root.
- The daemon has its own filter chain that determines what
files it will let the client access. This chain is not sent to the client
and is independent of any filters the client may have specified. Files
excluded by the daemon filter chain ( daemon-excluded files) are
treated as non-existent if the client tries to pull them, are skipped with
an error message if the client tries to push them (triggering exit code
23), and are never deleted from the module. You can use daemon filters to
prevent clients from downloading or tampering with private administrative
files, such as files you may add to support uid/gid name
- The daemon filter chain is built from the
"filter", "include from", "include",
"exclude from", and "exclude" parameters, in that
order of priority. Anchored patterns are anchored at the root of the
module. To prevent access to an entire subtree, for example,
"/secret", you must exclude everything in the subtree;
the easiest way to do this is with a triple-star pattern like
- The "filter" parameter takes a space-separated
list of daemon filter rules, though it is smart enough to know not to
split a token at an internal space in a rule (e.g. "- /foo -
/bar" is parsed as two rules). You may specify one or more merge-file
rules using the normal syntax. Only one "filter" parameter can
apply to a given module in the config file, so put all the rules you want
in a single parameter. Note that per-directory merge-file rules do not
provide as much protection as global rules, but they can be used to make
--delete work better during a client download operation if the
per-dir merge files are included in the transfer and the client requests
that they be used.
- This parameter takes a space-separated list of daemon
exclude patterns. As with the client --exclude option, patterns can
be qualified with "- " or "+ " to explicitly indicate
exclude/include. Only one "exclude" parameter can apply to a
given module. See the "filter" parameter for a description of
how excluded files affect the daemon.
- Use an "include" to override the effects of the
"exclude" parameter. Only one "include" parameter can
apply to a given module. See the "filter" parameter for a
description of how excluded files affect the daemon.
- exclude from
- This parameter specifies the name of a file on the daemon
that contains daemon exclude patterns, one per line. Only one
"exclude from" parameter can apply to a given module; if you
have multiple exclude-from files, you can specify them as a merge file in
the "filter" parameter. See the "filter" parameter for
a description of how excluded files affect the daemon.
- include from
- Analogue of "exclude from" for a file of daemon
include patterns. Only one "include from" parameter can apply to
a given module. See the "filter" parameter for a description of
how excluded files affect the daemon.
- incoming chmod
- This parameter allows you to specify a set of
comma-separated chmod strings that will affect the permissions of all
incoming files (files that are being received by the daemon). These
changes happen after all other permission calculations, and this will even
override destination-default and/or existing permissions when the client
does not specify --perms. See the description of the --chmod
rsync option and the chmod(1) manpage for information on the format
of this string.
- outgoing chmod
- This parameter allows you to specify a set of
comma-separated chmod strings that will affect the permissions of all
outgoing files (files that are being sent out from the daemon). These
changes happen first, making the sent permissions appear to be different
than those stored in the filesystem itself. For instance, you could
disable group write permissions on the server while having it appear to be
on to the clients. See the description of the --chmod rsync option
and the chmod(1) manpage for information on the format of this
- auth users
- This parameter specifies a comma and/or space-separated
list of authorization rules. In its simplest form, you list the usernames
that will be allowed to connect to this module. The usernames do not need
to exist on the local system. The rules may contain shell wildcard
characters that will be matched against the username provided by the
client for authentication. 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 protocol is used for this
exchange. The plain text usernames and passwords are stored in the file
specified by the "secrets file" parameter. The default is for
all users to be able to connect without a password (this is called
- In addition to username matching, you can specify groupname
matching via a ’@’ prefix. When using groupname matching,
the authenticating username must be a real user on the system, or it will
be assumed to be a member of no groups. For example, specifying
"@rsync" will match the authenticating user if the named user is
a member of the rsync group.
- Finally, options may be specified after a colon (:). The
options allow you to "deny" a user or a group, set the access to
"ro" (read-only), or set the access to "rw"
(read/write). Setting an auth-rule-specific ro/rw setting overrides the
module’s "read only" setting.
- Be sure to put the rules in the order you want them to be
matched, because the checking stops at the first matching user or group,
and that is the only auth that is checked. For example:
auth users = joe:deny @guest:deny admin:rw @rsync:ro susan joe sam
- In the above rule, user joe will be denied access no matter
what. Any user that is in the group "guest" is also denied
access. The user "admin" gets access in read/write mode, but
only if the admin user is not in group "guest" (because the
admin user-matching rule would never be reached if the user is in group
"guest"). Any other user who is in group "rsync" will
get read-only access. Finally, users susan, joe, and sam get the ro/rw
setting of the module, but only if the user didn’t match an earlier
- See the description of the secrets file for how you can
have per-user passwords as well as per-group passwords. It also explains
how a user can authenticate using their user password or (when applicable)
a group password, depending on what rule is being authenticated.
- See also the section entitled "USING RSYNC-DAEMON
FEATURES VIA A REMOTE SHELL CONNECTION" in rsync(1) for
information on how handle an rsyncd.conf-level username that differs from
the remote-shell-level username when using a remote shell to connect to an
- secrets file
- This parameter specifies the name of a file that contains
the username:password and/or @groupname:password pairs used for
authenticating this module. This file is only consulted if the "auth
users" parameter is specified. The file is line-based and contains
one name:password pair per line. Any line has a hash (#) as the very first
character on the line is considered a comment and is skipped. The
passwords can contain any characters 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
- The use of group-specific lines are only relevant when the
module is being authorized using a matching "@groupname" rule.
When that happens, the user can be authorized via either their
"username:password" line or the "@groupname:password"
line for the group that triggered the authentication.
- It is up to you what kind of password entries you want to
include, either users, groups, or both. The use of group rules in
"auth users" does not require that you specify a group password
if you do not want to use shared passwords.
- There is no default for the "secrets file"
parameter, you must choose a name (such as /etc/rsyncd.secrets). The file
must normally not be readable by "other"; see "strict
modes". If the file is not found or is rejected, no logins for a
"user auth" module will be possible.
- strict modes
- This parameter 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 parameter was
added to accommodate rsync running on the Windows operating system.
- hosts allow
- This parameter allows you to specify a list of patterns
that are matched against a connecting 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:
- 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.
- 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.
- an address/mask in the form ipaddr/maskaddr where ipaddr is
the IP address and maskaddr is the netmask in dotted decimal notation for
IPv4, or similar for IPv6, e.g. ffff:ffff:ffff:ffff:: instead of /64. All
IP addresses which match the masked IP address will be allowed in.
- a hostname pattern using wildcards. If the hostname of the
connecting IP (as determined by a reverse lookup) matches the wildcarded
name (using the same rules as normal unix filename matching), the client
is allowed in. This only works if "reverse lookup" is enabled
- a hostname. A plain hostname is matched against the reverse
DNS of the connecting IP (if "reverse lookup" is enabled),
and/or the IP of the given hostname is matched against the connecting IP
(if "forward lookup" is enabled, as it is by default). Any match
will be allowed in.
- Note IPv6 link-local addresses can have a scope in the
- You can also combine "hosts allow" with a
separate "hosts deny" parameter. If both parameters are
specified then the "hosts allow" parameter is checked first and
a match results in the client being able to connect. The "hosts
deny" parameter 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" parameter, which
means all hosts can connect.
- hosts deny
- This parameter allows you to specify a list of patterns
that are matched against a connecting clients hostname and IP address. If
the pattern matches then the connection is rejected. See the "hosts
allow" parameter for more information.
- The default is no "hosts deny" parameter, which
means all hosts can connect.
- reverse lookup
- Controls whether the daemon performs a reverse lookup on
the client’s IP address to determine its hostname, which is used
for "hosts allow"/"hosts deny" checks and the
"%h" log escape. This is enabled by default, but you may wish to
disable it to save time if you know the lookup will not return a useful
result, in which case the daemon will use the name
- If this parameter is enabled globally (even by default),
rsync performs the lookup as soon as a client connects, so disabling it
for a module will not avoid the lookup. Thus, you probably want to disable
it globally and then enable it for modules that need the information.
- forward lookup
- Controls whether the daemon performs a forward lookup on
any hostname specified in an hosts allow/deny setting. By default this is
enabled, allowing the use of an explicit hostname that would not be
returned by reverse DNS of the connecting IP.
- ignore errors
- This parameter tells rsyncd to ignore I/O errors on the
daemon when deciding whether to run the delete phase of the transfer.
Normally rsync skips the --delete step if any I/O errors have
occurred in order to prevent disastrous deletion due to a temporary
resource shortage or other I/O error. In some cases this test is counter
productive so you can use this parameter to turn off this behavior.
- ignore nonreadable
- This tells the rsync daemon 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
- This parameter enables per-file logging of downloads and
uploads in a format somewhat similar to that used by ftp daemons. The
daemon always logs the transfer at the end, so if a transfer is aborted,
no mention will be made in the log file.
- If you want to customize the log lines, see the "log
- log format
- This parameter allows you to specify the format used for
logging file transfers when transfer logging is enabled. The format is a
text string containing embedded single-character escape sequences prefixed
with a percent (%) character. An optional numeric field width may also be
specified between the percent and the escape letter (e.g. " %-50n
%8l %07p"). In addition, one or more apostrophes may be specified
prior to a numerical escape to indicate that the numerical value should be
made more human-readable. The 3 supported levels are the same as for the
--human-readable command-line option, though the default is for
human-readability to be off. Each added apostrophe increases the level
(e.g. " %''l %'b %f").
- The default log format is "%o %h [%a] %m (%u) %f
%l", and a "%t [%p] " is always prefixed when using the
"log file" parameter. (A perl script that will summarize this
default log format is included in the rsync source code distribution in
the "support" subdirectory: rsyncstats.)
- The single-character escapes that are understood are as
- %a the remote IP address (only available for a daemon)
- %b the number of bytes actually transferred
- %B the permission bits of the file (e.g. rwxrwxrwt)
- %c the total size of the block checksums received for the
basis file (only when sending)
- %C the full-file MD5 checksum if --checksum is
enabled or a file was transferred (only for protocol 30 or above).
- %f the filename (long form on sender; no trailing
- %G the gid of the file (decimal) or
- %h the remote host name (only available for a daemon)
- %i an itemized list of what is being updated
- %l the length of the file in bytes
- %L the string " -> SYMLINK", " =>
HARDLINK", or "" (where SYMLINK or HARDLINK
is a filename)
- %m the module name
- %M the last-modified time of the file
- %n the filename (short form; trailing "/" on
- %o the operation, which is "send",
"recv", or "del." (the latter includes the trailing
- %p the process ID of this rsync session
- %P the module path
- %t the current date time
- %u the authenticated username or an empty string
- %U the uid of the file (decimal)
- For a list of what the characters mean that are output by
"%i", see the --itemize-changes option in the rsync
- Note that some of the logged output changes when talking
with older rsync versions. For instance, deleted files were only output as
verbose messages prior to rsync 2.6.4.
- This parameter allows you to override the clients choice
for I/O timeout for this module. Using this parameter you can ensure that
rsync won’t wait on a dead client forever. The timeout is specified
in seconds. A value of zero means no timeout and is the default. A good
choice for anonymous rsync daemons may be 600 (giving a 10 minute
- refuse options
- This parameter allows you to specify a space-separated list
of rsync command line options that will be refused by your rsync daemon.
You may specify the full option name, its one-letter abbreviation, or a
wild-card string that matches multiple options. For example, this would
refuse --checksum (-c) and all the various delete
refuse options = c delete
- The reason the above refuses all delete options is that the
options imply --delete, and implied options are refused just like
explicit options. As an additional safety feature, the refusal of
"delete" also refuses remove-source-files when the daemon
is the sender; if you want the latter without the former, instead refuse
"delete-*" -- that refuses all the delete modes without
- When an option is refused, the daemon prints an error
message and exits. To prevent all compression when serving files, you can
use "dont compress = *" (see below) instead of "refuse
options = compress" to avoid returning an error to a client that
- dont compress
- This parameter allows you to select filenames based on
wildcard patterns that should not be compressed when pulling files from
the daemon (no analogous parameter exists to govern the pushing of files
to a daemon). Compression is expensive in terms of CPU usage, so it is
usually good to not try to compress files that won’t compress well,
such as already compressed files.
- The "dont compress" parameter takes a
space-separated list of case-insensitive wildcard patterns. Any source
filename matching one of the patterns will not be compressed during
- See the --skip-compress parameter in the
rsync(1) manpage for the list of file suffixes that are not
compressed by default. Specifying a value for the "dont
compress" parameter changes the default when the daemon is the
- pre-xfer exec, post-xfer exec
- You may specify a command to be run before and/or after the
transfer. If the pre-xfer exec command fails, the transfer is
aborted before it begins. Any output from the script on stdout (up to
several KB) will be displayed to the user when aborting, but is NOT
displayed if the script returns success. Any output from the script on
stderr goes to the daemon’s stderr, which is typically discarded
(though see --no-detatch option for a way to see the stderr output, which
can assist with debugging).
- The following environment variables will be set, though
some are specific to the pre-xfer or the post-xfer environment:
- RSYNC_MODULE_NAME: The name of the module being
- RSYNC_MODULE_PATH: The path configured for the
- RSYNC_HOST_ADDR: The accessing host’s IP
- RSYNC_HOST_NAME: The accessing host’s
- RSYNC_USER_NAME: The accessing user’s name
(empty if no user).
- RSYNC_PID: A unique number for this transfer.
- RSYNC_REQUEST: (pre-xfer only) The module/path info
specified by the user. Note that the user can specify multiple source
files, so the request can be something like "mod/path1
- RSYNC_ARG#: (pre-xfer only) The pre-request
arguments are set in these numbered values. RSYNC_ARG0 is always
"rsyncd", followed by the options that were used in RSYNC_ARG1,
and so on. There will be a value of "." indicating that the
options are done and the path args are beginning -- these contain similar
information to RSYNC_REQUEST, but with values separated and the module
name stripped off.
- RSYNC_EXIT_STATUS: (post-xfer only) the server
side’s exit value. This will be 0 for a successful run, a positive
value for an error that the server generated, or a -1 if rsync failed to
exit properly. Note that an error that occurs on the client side does not
currently get sent to the server side, so this is not the final exit
status for the whole transfer.
- RSYNC_RAW_STATUS: (post-xfer only) the raw exit
value from waitpid() .
- Even though the commands can be associated with a
particular module, they are run using the permissions of the user that
started the daemon (not the module’s uid/gid setting) without any
There are currently two config directives available that allow a config file to
incorporate the contents of other files: &include
. Both allow a reference to either a file or a directory.
They differ in how segregated the file’s contents are considered to be.
directive treats each file as more distinct, with each
one inheriting the defaults of the parent file, starting the parameter parsing
as globals/defaults, and leaving the defaults unchanged for the parsing of the
rest of the parent file.
directive, on the other hand, treats the file’s
contents as if it were simply inserted in place of the directive, and thus it
can set parameters in a module started in another file, can affect the
defaults for other files, etc.
When an &include
directive refers to a
directory, it will read in all the *.conf
(respectively) that are contained inside that directory (without any recursive
scanning), with the files sorted into alpha order. So, if you have a directory
named "rsyncd.d" with the files "foo.conf",
"bar.conf", and "baz.conf" inside it, this directive:
would be the same as this set of directives:
except that it adjusts as files are added and removed from the directory.
The advantage of the &include
directive is that you can define one or
more modules in a separate file without worrying about unintended side-effects
between the self-contained module files.
The advantage of the &merge
directive is that you can load config
snippets that can be included into multiple module definitions, and you can
also set global values that will affect connections (such as motd
), or globals that will affect other include files.
For example, this is a useful /etc/rsyncd.conf file:
port = 873
log file = /var/log/rsync.log
pid file = /var/lock/rsync.lock
This would merge any /etc/rsyncd.d/*.inc files (for global values that should
stay in effect), and then include any /etc/rsyncd.d/*.conf files (defining
modules without any global-value cross-talk).
The authentication protocol used in rsync is a 128 bit MD4 based challenge
response system. This is fairly weak protection, though (with at least one
brute-force hash-finding algorithm publicly available), so if you want really
top-quality security, then I recommend that you run rsync over ssh. (Yes, a
future version of rsync will switch over to a stronger hashing method.)
Also note that the rsync daemon protocol does not currently provide any
encryption of the data that is transferred over the connection. 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.
A simple rsyncd.conf file that allow anonymous rsync to a ftp area at /home/ftp
path = /home/ftp
comment = ftp export area
A more sophisticated example would be:
uid = nobody
gid = nobody
use chroot = yes
max connections = 4
syslog facility = local5
pid file = /var/run/rsyncd.pid
path = /var/ftp/./pub
comment = whole ftp area (approx 6.1 GB)
path = /var/ftp/./pub/samba
comment = Samba ftp area (approx 300 MB)
path = /var/ftp/./pub/rsync
comment = rsync ftp area (approx 6 MB)
path = /public_html/samba
comment = Samba WWW pages (approx 240 MB)
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:
/etc/rsyncd.conf or rsyncd.conf
Please report bugs! The rsync bug tracking system is online at
This man page is current for version 3.1.2 of rsync.
rsync is distributed under the GNU General Public License. See the file COPYING
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
Thanks to Warren Stanley for his original idea and patch for the rsync daemon.
Thanks to Karsten Thygesen for his many suggestions and documentation!
rsync was written by Andrew Tridgell and Paul Mackerras. Many people have later
contributed to it.
Mailing lists for support and development are available at