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manpage(rsyncd.conf)(5)(22 Jun 2014)()()

manpagename(rsyncd.conf)(configuration file for rsync in daemon mode)

manpagesynopsis()

rsyncd.conf

manpagedescription()

The rsyncd.conf file is the runtime configuration file for rsync when

run as an rsync daemon.

The rsyncd.conf file controls authentication, access, logging and

available modules.

manpagesection(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 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 bf(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.

manpagesection(LAUNCHING THE RSYNC DAEMON)

The rsync daemon is launched by specifying the bf(--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 "bf(rsync --daemon)" from a suitable startup script.

When run via inetd you should add a line like this to /etc/services:

verb( rsync 873/tcp)

and a single line something like this to /etc/inetd.conf:

verb( 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 bf(not) send the rsync daemon a HUP signal to force

it to reread the tt(rsyncd.conf) file. The file is re-read on each client

connection.

manpagesection(GLOBAL PARAMETERS)

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.

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 %%.

startdit()

dit(bf(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 bf(--dparam=motdfile=FILE)

command-line option when starting the daemon.

dit(bf(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 bf(--dparam=pidfile=FILE)

command-line option when starting the daemon.

dit(bf(port)) 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 bf(--port) command-line option.

dit(bf(address)) 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 bf(--address) command-line option.

dit(bf(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 code(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 bf(--sockopts) command-line option.

dit(bf(listen backlog)) You can override the default backlog value when the

daemon listens for connections. It defaults to 5.

enddit()

manpagesection(MODULE PARAMETERS)

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.

As with GLOBAL PARAMETERS, you may use references to environment variables in

the values of parameters. See the GLOBAL PARAMETERS section for more details.

startdit()

dit(bf(comment)) 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.

dit(bf(path)) 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 tt(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:

verb( 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.

dit(bf(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

bf(--backup-dir), bf(--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, rsync will not attempt to map users and groups

by name (by default), but instead copy IDs as though bf(--numeric-ids) had

been specified. In order to enable name-mapping, rsync needs to be able to

use the standard library functions for looking up names and IDs (i.e.

code(getpwuid()), code(getgrgid()), code(getpwname()), and code(getgrnam())).

This means the rsync

process in the chroot hierarchy will need to have access to the resources

used by these library functions (traditionally /etc/passwd and

/etc/group, but perhaps additional dynamic libraries as well).

If you copy the necessary 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 the "numeric ids" daemon parameter (see below).

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.

dit(bf(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 bf(--numeric-ids) command-line option. By default, this parameter is

enabled for chroot modules and disabled for non-chroot modules.

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.

dit(bf(munge symlinks)) This parameter tells rsync to modify

all symlinks in the same way as the (non-daemon-affecting)

bf(--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 allow).

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.

dit(bf(charset)) This specifies the name of the character set in which the

module's filenames are stored. If the client uses an bf(--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 bf(--iconv) option is

refused, just as if "iconv" had been specified via "refuse options".

If you wish to force users to always use bf(--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.

dit(bf(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.

dit(bf(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 code(syslog()) doesn't work for chrooted programs. The file is

opened before code(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 error.)

This setting can be overridden by using the bf(--log-file=FILE) or

bf(--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.

dit(bf(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 settings).

dit(bf(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 bf(--info) and

bf(--debug) logging. If the max value is 2, then no info and/or debug value

that is higher than what would be set by bf(-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.

dit(bf(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 tt(/var/run/rsyncd.lock).

dit(bf(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.

dit(bf(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.

dit(bf(list)) 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 listable.

dit(bf(uid)) 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:

verb( uid = %RSYNC_USER_NAME%

gid = * )

dit(bf(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).

dit(bf(fake super)) Setting "fake super = yes" for a module causes the

daemon side to behave as if the bf(--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.

dit(bf(filter)) 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 (bf(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 translations.

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 em(must) exclude everything in the

subtree; the easiest way to do this is with a triple-star pattern like

"/secret/***".

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 bf(--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.

dit(bf(exclude)) This parameter takes a space-separated list of daemon

exclude patterns. As with the client bf(--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.

dit(bf(include)) 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.

dit(bf(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.

dit(bf(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.

dit(bf(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 bf(--perms).

See the description of the bf(--chmod) rsync option and the bf(chmod)(1)

manpage for information on the format of this string.

dit(bf(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 bf(--chmod) rsync option and the bf(chmod)(1)

manpage for information on the format of this string.

dit(bf(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 "anonymous rsync").

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:

verb( 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 group-matching rule.

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 bf(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 rsync daemon.

dit(bf(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 work.

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 tt(/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.

dit(bf(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.

dit(bf(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:

quote(itemization(

it() 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.

it() 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.

it() 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.

it() 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 (the default).

it() 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 address specification:

quote(

tt( fe80::1%link1)nl()

tt( fe80::%link1/64)nl()

tt( fe80::%link1/ffff:ffff:ffff:ffff::)nl()

)

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.

dit(bf(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.

dit(bf(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

"UNDETERMINED" instead.

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.

dit(bf(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.

dit(bf(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 bf(--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.

dit(bf(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.

dit(bf(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 format" parameter.

dit(bf(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. "bf(%-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 bf(--human-readable)

command-line option, though the default is for human-readability to be off.

Each added apostrophe increases the level (e.g. "bf(%''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 follows:

quote(itemization(

it() %a the remote IP address (only available for a daemon)

it() %b the number of bytes actually transferred

it() %B the permission bits of the file (e.g. rwxrwxrwt)

it() %c the total size of the block checksums received for the basis file (only when sending)

it() %C the full-file MD5 checksum if bf(--checksum) is enabled or a file was transferred (only for protocol 30 or above).

it() %f the filename (long form on sender; no trailing "/")

it() %G the gid of the file (decimal) or "DEFAULT"

it() %h the remote host name (only available for a daemon)

it() %i an itemized list of what is being updated

it() %l the length of the file in bytes

it() %L the string " -> SYMLINK", " => HARDLINK", or "" (where bf(SYMLINK) or bf(HARDLINK) is a filename)

it() %m the module name

it() %M the last-modified time of the file

it() %n the filename (short form; trailing "/" on dir)

it() %o the operation, which is "send", "recv", or "del." (the latter includes the trailing period)

it() %p the process ID of this rsync session

it() %P the module path

it() %t the current date time

it() %u the authenticated username or an empty string

it() %U the uid of the file (decimal)

))

For a list of what the characters mean that are output by "%i", see the

bf(--itemize-changes) option in the rsync manpage.

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.

dit(bf(timeout)) 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 timeout).

dit(bf(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 bf(--checksum) (bf(-c)) and all the various

delete options:

quote(tt( refuse options = c delete))

The reason the above refuses all delete options is that the options imply

bf(--delete), and implied options are refused just like explicit options.

As an additional safety feature, the refusal of "delete" also refuses

bf(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 affecting bf(--remove-source-files).

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 requests compression.

dit(bf(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 transfer.

See the bf(--skip-compress) parameter in the bf(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 sender.

dit(bf(pre-xfer exec), bf(post-xfer exec)) You may specify a command to be run

before and/or after the transfer. If the bf(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:

quote(itemization(

it() bf(RSYNC_MODULE_NAME): The name of the module being accessed.

it() bf(RSYNC_MODULE_PATH): The path configured for the module.

it() bf(RSYNC_HOST_ADDR): The accessing host's IP address.

it() bf(RSYNC_HOST_NAME): The accessing host's name.

it() bf(RSYNC_USER_NAME): The accessing user's name (empty if no user).

it() bf(RSYNC_PID): A unique number for this transfer.

it() bf(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 mod/path2", etc.

it() bf(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.

it() bf(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.

it() bf(RSYNC_RAW_STATUS): (post-xfer only) the raw exit value from code(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 chroot restrictions.

enddit()

manpagesection(CONFIG DIRECTIVES)

There are currently two config directives available that allow a config file to

incorporate the contents of other files: bf(&include) and bf(&merge). Both

allow a reference to either a file or a directory. They differ in how

segregated the file's contents are considered to be.

The bf(&include) 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.

The bf(&merge) 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 bf(&include) or bf(&merge) directive refers to a directory, it will read

in all the bf(*.conf) or bf(*.inc) files (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:

verb( &include /path/rsyncd.d )

would be the same as this set of directives:

verb( &include /path/rsyncd.d/bar.conf

&include /path/rsyncd.d/baz.conf

&include /path/rsyncd.d/foo.conf )

except that it adjusts as files are added and removed from the directory.

The advantage of the bf(&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 bf(&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 bf(motd file)), or globals

that will affect other include files.

For example, this is a useful /etc/rsyncd.conf file:

verb( port = 873

log file = /var/log/rsync.log

pid file = /var/lock/rsync.lock

&merge /etc/rsyncd.d

&include /etc/rsyncd.d )

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).

manpagesection(AUTHENTICATION STRENGTH)

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.

manpagesection(EXAMPLES)

A simple rsyncd.conf file that allow anonymous rsync to a ftp area at

tt(/home/ftp) would be:

verb(

[ftp]

path = /home/ftp

comment = ftp export area

)

A more sophisticated example would be:

verb(

uid = nobody

gid = nobody

use chroot = yes

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:

quote(

tt(tridge:mypass)nl()

tt(susan:herpass)nl()

)

manpagefiles()

/etc/rsyncd.conf or rsyncd.conf

manpageseealso()

bf(rsync)(1)

manpagediagnostics()

manpagebugs()

Please report bugs! The rsync bug tracking system is online at

url(http://rsync.samba.org/)(http://rsync.samba.org/)

manpagesection(VERSION)

This man page is current for version 3.1.1 of rsync.

manpagesection(CREDITS)

rsync is distributed under the GNU General Public License. See the file

COPYING for details.

The primary ftp site for rsync is

url(ftp://rsync.samba.org/pub/rsync)(ftp://rsync.samba.org/pub/rsync).

A WEB site is available at

url(http://rsync.samba.org/)(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.

manpagesection(THANKS)

Thanks to Warren Stanley for his original idea and patch for the rsync

daemon. Thanks to Karsten Thygesen for his many suggestions and

documentation!

manpageauthor()

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

url(http://lists.samba.org)(lists.samba.org)