前往小程序,Get更优阅读体验!
立即前往
首页
学习
活动
专区
工具
TVP
发布
社区首页 >专栏 >rsync 运维利器,同步工具

rsync 运维利器,同步工具

作者头像
WindWant
发布2020-09-11 15:24:25
2.3K0
发布2020-09-11 15:24:25
举报
文章被收录于专栏:后端码事

NAME

rsync - faster, flexible replacement for rcp

SYNOPSIS

rsync [OPTION]... SRC [SRC]... DEST

rsync [OPTION]... SRC [SRC]... [USER@]HOST:DEST

rsync [OPTION]... SRC [SRC]... [USER@]HOST::DEST

rsync [OPTION]... SRC [SRC]... rsync://[USER@]HOST[:PORT]/DEST

rsync [OPTION]... SRC

rsync [OPTION]... [USER@]HOST:SRC [DEST]

rsync [OPTION]... [USER@]HOST::SRC [DEST]

rsync [OPTION]... rsync://[USER@]HOST[:PORT]/SRC [DEST]

DESCRIPTION

rsync is a program that behaves in much the same way that rcp does, but

has many more options and uses the rsync remote-update protocol to

greatly speed up file transfers when the destination file is being

updated.

The rsync remote-update protocol allows rsync to transfer just the dif-

ferences between two sets of files across the network connection, using

an efficient checksum-search algorithm described in the technical

report that accompanies this package.

Some of the additional features of rsync are:

o support for copying links, devices, owners, groups, and permis-

sions

o exclude and exclude-from options similar to GNU tar

o a CVS exclude mode for ignoring the same files that CVS would

ignore

o can use any transparent remote shell, including ssh or rsh

o does not require super-user privileges

o pipelining of file transfers to minimize latency costs

o support for anonymous or authenticated rsync daemons (ideal for

mirroring)

GENERAL

Rsync copies files either to or from a remote host, or locally on the

current host (it does not support copying files between two remote

hosts).

There are two different ways for rsync to contact a remote system:

using a remote-shell program as the transport (such as ssh or rsh) or

contacting an rsync daemon directly via TCP. The remote-shell trans-

port is used whenever the source or destination path contains a single

colon (:) separator after a host specification. Contacting an rsync

daemon directly happens when the source or destination path contains a

double colon (::) separator after a host specification, OR when an

rsync:// URL is specified (see also the "USING RSYNC-DAEMON FEATURES

VIA A REMOTE-SHELL CONNECTION" section for an exception to this latter

rule).

As a special case, if a single source arg is specified without a desti-

nation, the files are listed in an output format similar to "ls -l".

As expected, if neither the source or destination path specify a remote

host, the copy occurs locally (see also the --list-only option).

SETUP

See the file README for installation instructions.

Once installed, you can use rsync to any machine that you can access

via a remote shell (as well as some that you can access using the rsync

daemon-mode protocol). For remote transfers, a modern rsync uses ssh

for its communications, but it may have been configured to use a dif-

ferent remote shell by default, such as rsh or remsh.

You can also specify any remote shell you like, either by using the -e

command line option, or by setting the RSYNC_RSH environment variable.

Note that rsync must be installed on both the source and destination

machines.

USAGE

You use rsync in the same way you use rcp. You must specify a source

and a destination, one of which may be remote.

Perhaps the best way to explain the syntax is with some examples:

rsync -t *.c foo:src/

This would transfer all files matching the pattern *.c from the current

directory to the directory src on the machine foo. If any of the files

already exist on the remote system then the rsync remote-update proto-

col is used to update the file by sending only the differences. See the

tech report for details.

rsync -avz foo:src/bar /data/tmp

This would recursively transfer all files from the directory src/bar on

the machine foo into the /data/tmp/bar directory on the local machine.

The files are transferred in "archive" mode, which ensures that sym-

bolic links, devices, attributes, permissions, ownerships, etc. are

preserved in the transfer. Additionally, compression will be used to

reduce the size of data portions of the transfer.

rsync -avz foo:src/bar/ /data/tmp

A trailing slash on the source changes this behavior to avoid creating

an additional directory level at the destination. You can think of a

trailing / on a source as meaning "copy the contents of this directory"

as opposed to "copy the directory by name", but in both cases the

attributes of the containing directory are transferred to the contain-

ing directory on the destination. In other words, each of the follow-

ing commands copies the files in the same way, including their setting

of the attributes of /dest/foo:

rsync -av /src/foo /dest

rsync -av /src/foo/ /dest/foo

Note also that host and module references don't require a trailing

slash to copy the contents of the default directory. For example, both

of these copy the remote directory's contents into "/dest":

rsync -av host: /dest

rsync -av host::module /dest

You can also use rsync in local-only mode, where both the source and

destination don't have a ':' in the name. In this case it behaves like

an improved copy command.

Finally, you can list all the (listable) modules available from a par-

ticular rsync daemon by leaving off the module name:

rsync somehost.mydomain.com::

See the following section for more details.

ADVANCED USAGE

The syntax for requesting multiple files from a remote host involves

using quoted spaces in the SRC. Some examples:

rsync host::'modname/dir1/file1 modname/dir2/file2' /dest

This would copy file1 and file2 into /dest from an rsync daemon. Each

additional arg must include the same "modname/" prefix as the first

one, and must be preceded by a single space. All other spaces are

assumed to be a part of the filenames.

rsync -av host:'dir1/file1 dir2/file2' /dest

This would copy file1 and file2 into /dest using a remote shell. This

word-splitting is done by the remote shell, so if it doesn't work it

means that the remote shell isn't configured to split its args based on

whitespace (a very rare setting, but not unknown). If you need to

transfer a filename that contains whitespace, you'll need to either

escape the whitespace in a way that the remote shell will understand,

or use wildcards in place of the spaces. Two examples of this are:

rsync -av host:'file\ name\ with\ spaces' /dest

rsync -av host:file?name?with?spaces /dest

This latter example assumes that your shell passes through unmatched

wildcards. If it complains about "no match", put the name in quotes.

CONNECTING TO AN RSYNC DAEMON

It is also possible to use rsync without a remote shell as the trans-

port. In this case you will directly connect to a remote rsync daemon,

typically using TCP port 873. (This obviously requires the daemon to

be running on the remote system, so refer to the STARTING AN RSYNC DAE-

MON TO ACCEPT CONNECTIONS section below for information on that.)

Using rsync in this way is the same as using it with a remote shell

except that:

o you either use a double colon :: instead of a single colon to

separate the hostname from the path, or you use an rsync:// URL.

o the first word of the "path" is actually a module name.

o the remote daemon may print a message of the day when you con-

nect.

o if you specify no path name on the remote daemon then the list

of accessible paths on the daemon will be shown.

o if you specify no local destination then a listing of the speci-

fied files on the remote daemon is provided.

o you must not specify the --rsh (-e) option.

An example that copies all the files in a remote module named "src":

rsync -av host::src /dest

Some modules on the remote daemon may require authentication. If so,

you will receive a password prompt when you connect. You can avoid the

password prompt by setting the environment variable RSYNC_PASSWORD to

the password you want to use or using the --password-file option. This

may be useful when scripting rsync.

WARNING: On some systems environment variables are visible to all

users. On those systems using --password-file is recommended.

You may establish the connection via a web proxy by setting the envi-

ronment variable RSYNC_PROXY to a hostname:port pair pointing to your

web proxy. Note that your web proxy's configuration must support proxy

connections to port 873.

USING RSYNC-DAEMON FEATURES VIA A REMOTE-SHELL CONNECTION

It is sometimes useful to use various features of an rsync daemon (such

as named modules) without actually allowing any new socket connections

into a system (other than what is already required to allow remote-

shell access). Rsync supports connecting to a host using a remote

shell and then spawning a single-use "daemon" server that expects to

read its config file in the home dir of the remote user. This can be

useful if you want to encrypt a daemon-style transfer's data, but since

the daemon is started up fresh by the remote user, you may not be able

to use features such as chroot or change the uid used by the daemon.

(For another way to encrypt a daemon transfer, consider using ssh to

tunnel a local port to a remote machine and configure a normal rsync

daemon on that remote host to only allow connections from "localhost".)

From the user's perspective, a daemon transfer via a remote-shell con-

nection uses nearly the same command-line syntax as a normal rsync-dae-

mon transfer, with the only exception being that you must explicitly

set the remote shell program on the command-line with the --rsh=COMMAND

option. (Setting the RSYNC_RSH in the environment will not turn on

this functionality.) For example:

rsync -av --rsh=ssh host::module /dest

If you need to specify a different remote-shell user, keep in mind that

the user@ prefix in front of the host is specifying the rsync-user

value (for a module that requires user-based authentication). This

means that you must give the '-l user' option to ssh when specifying

the remote-shell, as in this example that uses the short version of the

--rsh option:

rsync -av -e "ssh -l ssh-user" rsync-user@host::module /dest

The "ssh-user" will be used at the ssh level; the "rsync-user" will be

used to log-in to the "module".

STARTING AN RSYNC DAEMON TO ACCEPT CONNECTIONS

In order to connect to an rsync daemon, the remote system needs to have

a daemon already running (or it needs to have configured something like

inetd to spawn an rsync daemon for incoming connections on a particular

port). For full information on how to start a daemon that will han-

dling incoming socket connections, see the rsyncd.conf(5) man page --

that is the config file for the daemon, and it contains the full

details for how to run the daemon (including stand-alone and inetd con-

figurations).

If you're using one of the remote-shell transports for the transfer,

there is no need to manually start an rsync daemon.

EXAMPLES

Here are some examples of how I use rsync.

To backup my wife's home directory, which consists of large MS Word

files and mail folders, I use a cron job that runs

rsync -Cavz . arvidsjaur:backup

each night over a PPP connection to a duplicate directory on my machine

"arvidsjaur".

To synchronize my samba source trees I use the following Makefile tar-

gets:

get:

rsync -avuzb --exclude '*~' samba:samba/ .

put:

rsync -Cavuzb . samba:samba/

sync: get put

this allows me to sync with a CVS directory at the other end of the

connection. I then do CVS operations on the remote machine, which saves

a lot of time as the remote CVS protocol isn't very efficient.

I mirror a directory between my "old" and "new" ftp sites with the com-

mand:

rsync -az -e ssh --delete ~ftp/pub/samba nimbus:"~ftp/pub/tridge"

This is launched from cron every few hours.

OPTIONS SUMMARY

Here is a short summary of the options available in rsync. Please refer

to the detailed description below for a complete description.

-v, --verbose increase verbosity

-q, --quiet suppress non-error messages

--no-motd suppress daemon-mode MOTD (see caveat)

-c, --checksum skip based on checksum, not mod-time & size

-a, --archive archive mode; same as -rlptgoD (no -H)

--no-OPTION turn off an implied OPTION (e.g. --no-D)

-r, --recursive recurse into directories

-R, --relative use relative path names

--no-implied-dirs don't send implied dirs with --relative

-b, --backup make backups (see --suffix & --backup-dir)

--backup-dir=DIR make backups into hierarchy based in DIR

--suffix=SUFFIX backup suffix (default ~ w/o --backup-dir)

-u, --update skip files that are newer on the receiver

--inplace update destination files in-place

--append append data onto shorter files

-d, --dirs transfer directories without recursing

-l, --links copy symlinks as symlinks

-L, --copy-links transform symlink into referent file/dir

--copy-unsafe-links only "unsafe" symlinks are transformed

--safe-links ignore symlinks that point outside the tree

-k, --copy-dirlinks transform symlink to dir into referent dir

-K, --keep-dirlinks treat symlinked dir on receiver as dir

-H, --hard-links preserve hard links

-p, --perms preserve permissions

--executability preserve executability

--chmod=CHMOD affect file and/or directory permissions

-o, --owner preserve owner (super-user only)

-g, --group preserve group

--devices preserve device files (super-user only)

--specials preserve special files

-D same as --devices --specials

-t, --times preserve times

-O, --omit-dir-times omit directories when preserving times

--super receiver attempts super-user activities

-S, --sparse handle sparse files efficiently

-n, --dry-run show what would have been transferred

-W, --whole-file copy files whole (without rsync algorithm)

-x, --one-file-system don't cross filesystem boundaries

-B, --block-size=SIZE force a fixed checksum block-size

-e, --rsh=COMMAND specify the remote shell to use

--rsync-path=PROGRAM specify the rsync to run on remote machine

--existing skip creating new files on receiver

--ignore-existing skip updating files that exist on receiver

--remove-source-files sender removes synchronized files (non-dir)

--del an alias for --delete-during

--delete delete extraneous files from dest dirs

--delete-before receiver deletes before transfer (default)

--delete-during receiver deletes during xfer, not before

--delete-after receiver deletes after transfer, not before

--delete-excluded also delete excluded files from dest dirs

--ignore-errors delete even if there are I/O errors

--force force deletion of dirs even if not empty

--max-delete=NUM don't delete more than NUM files

--max-size=SIZE don't transfer any file larger than SIZE

--min-size=SIZE don't transfer any file smaller than SIZE

--partial keep partially transferred files

--partial-dir=DIR put a partially transferred file into DIR

--delay-updates put all updated files into place at end

-m, --prune-empty-dirs prune empty directory chains from file-list

--numeric-ids don't map uid/gid values by user/group name

--timeout=TIME set I/O timeout in seconds

-I, --ignore-times don't skip files that match size and time

--size-only skip files that match in size

--modify-window=NUM compare mod-times with reduced accuracy

-T, --temp-dir=DIR create temporary files in directory DIR

-y, --fuzzy find similar file for basis if no dest file

--compare-dest=DIR also compare received files relative to DIR

--copy-dest=DIR ... and include copies of unchanged files

--link-dest=DIR hardlink to files in DIR when unchanged

-z, --compress compress file data during the transfer

--compress-level=NUM explicitly set compression level

-C, --cvs-exclude auto-ignore files in the same way CVS does

-f, --filter=RULE add a file-filtering RULE

-F same as --filter='dir-merge /.rsync-filter'

repeated: --filter='- .rsync-filter'

--exclude=PATTERN exclude files matching PATTERN

--exclude-from=FILE read exclude patterns from FILE

--include=PATTERN don't exclude files matching PATTERN

--include-from=FILE read include patterns from FILE

--files-from=FILE read list of source-file names from FILE

-0, --from0 all *from/filter files are delimited by 0s

--address=ADDRESS bind address for outgoing socket to daemon

--port=PORT specify double-colon alternate port number

--sockopts=OPTIONS specify custom TCP options

--blocking-io use blocking I/O for the remote shell

--stats give some file-transfer stats

-8, --8-bit-output leave high-bit chars unescaped in output

-h, --human-readable output numbers in a human-readable format

--progress show progress during transfer

-P same as --partial --progress

-i, --itemize-changes output a change-summary for all updates

--out-format=FORMAT output updates using the specified FORMAT

--log-file=FILE log what we're doing to the specified FILE

--log-file-format=FMT log updates using the specified FMT

--password-file=FILE read password from FILE

--list-only list the files instead of copying them

--bwlimit=KBPS limit I/O bandwidth; KBytes per second

--write-batch=FILE write a batched update to FILE

--only-write-batch=FILE like --write-batch but w/o updating dest

--read-batch=FILE read a batched update from FILE

--protocol=NUM force an older protocol version to be used

--checksum-seed=NUM set block/file checksum seed (advanced)

-4, --ipv4 prefer IPv4

-6, --ipv6 prefer IPv6

-E, --extended-attributes copy extended attributes, resource forks

--cache disable fcntl(F_NOCACHE)

--version print version number

(-h) --help show this help (see below for -h comment)

Rsync can also be run as a daemon, in which case the following options

are accepted:

--daemon run as an rsync daemon

--address=ADDRESS bind to the specified address

--bwlimit=KBPS limit I/O bandwidth; KBytes per second

--config=FILE specify alternate rsyncd.conf file

--no-detach do not detach from the parent

--port=PORT listen on alternate port number

--log-file=FILE override the "log file" setting

--log-file-format=FMT override the "log format" setting

--sockopts=OPTIONS specify custom TCP options

-v, --verbose increase verbosity

-4, --ipv4 prefer IPv4

-6, --ipv6 prefer IPv6

-h, --help show this help (if used after --daemon)

OPTIONS

rsync uses the GNU long options package. Many of the command line

options have two variants, one short and one long. These are shown

below, separated by commas. Some options only have a long variant. The

'=' for options that take a parameter is optional; whitespace can be

used instead.

--help Print a short help page describing the options available in

rsync and exit. For backward-compatibility with older versions

of rsync, the help will also be output if you use the -h option

without any other args.

--version

print the rsync version number and exit.

-v, --verbose

This option increases the amount of information you are given

during the transfer. By default, rsync works silently. A single

-v will give you information about what files are being trans-

ferred and a brief summary at the end. Two -v flags will give

you information on what files are being skipped and slightly

more information at the end. More than two -v flags should only

be used if you are debugging rsync.

Note that the names of the transferred files that are output are

done using a default --out-format of "%n%L", which tells you

just the name of the file and, if the item is a link, where it

points. At the single -v level of verbosity, this does not men-

tion when a file gets its attributes changed. If you ask for an

itemized list of changed attributes (either --itemize-changes or

adding "%i" to the --out-format setting), the output (on the

client) increases to mention all items that are changed in any

way. See the --out-format option for more details.

-q, --quiet

This option decreases the amount of information you are given

during the transfer, notably suppressing information messages

from the remote server. This flag is useful when invoking rsync

from cron.

--no-motd

This option affects the information that is output by the client

at the start of a daemon transfer. This suppresses the message-

of-the-day (MOTD) text, but it also affects the list of modules

that the daemon sends in response to the "rsync host::" request

(due to a limitation in the rsync protocol), so omit this option

if you want to request the list of modules from the deamon.

-I, --ignore-times

Normally rsync will skip any files that are already the same

size and have the same modification time-stamp. This option

turns off this "quick check" behavior, causing all files to be

updated.

--size-only

Normally rsync will not transfer any files that are already the

same size and have the same modification time-stamp. With the

--size-only option, files will not be transferred if they have

the same size, regardless of timestamp. This is useful when

starting to use rsync after using another mirroring system which

may not preserve timestamps exactly.

--modify-window

When comparing two timestamps, rsync treats the timestamps as

being equal if they differ by no more than the modify-window

value. This is normally 0 (for an exact match), but you may

find it useful to set this to a larger value in some situations.

In particular, when transferring to or from an MS Windows FAT

filesystem (which represents times with a 2-second resolution),

--modify-window=1 is useful (allowing times to differ by up to 1

second).

-c, --checksum

This forces the sender to checksum every regular file using a

128-bit MD4 checksum. It does this during the initial file-sys-

tem scan as it builds the list of all available files. The

receiver then checksums its version of each file (if it exists

and it has the same size as its sender-side counterpart) in

order to decide which files need to be updated: files with

either a changed size or a changed checksum are selected for

transfer. Since this whole-file checksumming of all files on

both sides of the connection occurs in addition to the automatic

checksum verifications that occur during a file's transfer, this

option can be quite slow.

Note that rsync always verifies that each transferred file was

correctly reconstructed on the receiving side by checking its

whole-file checksum, but that automatic after-the-transfer veri-

fication has nothing to do with this option's before-the-trans-

fer "Does this file need to be updated?" check.

-a, --archive

This is equivalent to -rlptgoD. It is a quick way of saying you

want recursion and want to preserve almost everything (with -H

being a notable omission). The only exception to the above

equivalence is when --files-from is specified, in which case -r

is not implied.

Note that -a does not preserve hardlinks, because finding multi-

ply-linked files is expensive. You must separately specify -H.

--no-OPTION

You may turn off one or more implied options by prefixing the

option name with "no-". Not all options may be prefixed with a

"no-": only options that are implied by other options (e.g.

--no-D, --no-perms) or have different defaults in various cir-

cumstances (e.g. --no-whole-file, --no-blocking-io, --no-dirs).

You may specify either the short or the long option name after

the "no-" prefix (e.g. --no-R is the same as --no-relative).

For example: if you want to use -a (--archive) but don't want -o

(--owner), instead of converting -a into -rlptgD, you could

specify -a --no-o (or -a --no-owner).

The order of the options is important: if you specify --no-r

-a, the -r option would end up being turned on, the opposite of

-a --no-r. Note also that the side-effects of the --files-from

option are NOT positional, as it affects the default state of

several options and slightly changes the meaning of -a (see the

--files-from option for more details).

-r, --recursive

This tells rsync to copy directories recursively. See also

--dirs (-d).

-R, --relative

Use relative paths. This means that the full path names speci-

fied on the command line are sent to the server rather than just

the last parts of the filenames. This is particularly useful

when you want to send several different directories at the same

time. For example, if you used this command:

rsync -av /foo/bar/baz.c remote:/tmp/

... this would create a file named baz.c in /tmp/ on the remote

machine. If instead you used

rsync -avR /foo/bar/baz.c remote:/tmp/

then a file named /tmp/foo/bar/baz.c would be created on the

remote machine -- the full path name is preserved. To limit the

amount of path information that is sent, you have a couple

options: (1) With a modern rsync on the sending side (beginning

with 2.6.7), you can insert a dot and a slash into the source

path, like this:

rsync -avR /foo/./bar/baz.c remote:/tmp/

That would create /tmp/bar/baz.c on the remote machine. (Note

that the dot must be followed by a slash, so "/foo/." would not

be abbreviated.) (2) For older rsync versions, you would need

to use a chdir to limit the source path. For example, when

pushing files:

(cd /foo; rsync -avR bar/baz.c remote:/tmp/)

(Note that the parens put the two commands into a sub-shell, so

that the "cd" command doesn't remain in effect for future com-

mands.) If you're pulling files, use this idiom (which doesn't

work with an rsync daemon):

rsync -avR --rsync-path="cd /foo; rsync" \

remote:bar/baz.c /tmp/

--no-implied-dirs

This option affects the default behavior of the --relative

option. When it is specified, the attributes of the implied

directories from the source names are not included in the trans-

fer. This means that the corresponding path elements on the

destination system are left unchanged if they exist, and any

missing implied directories are created with default attributes.

This even allows these implied path elements to have big differ-

ences, such as being a symlink to a directory on one side of the

transfer, and a real directory on the other side.

For instance, if a command-line arg or a files-from entry told

rsync to transfer the file "path/foo/file", the directories

"path" and "path/foo" are implied when --relative is used. If

"path/foo" is a symlink to "bar" on the destination system, the

receiving rsync would ordinarily delete "path/foo", recreate it

as a directory, and receive the file into the new directory.

With --no-implied-dirs, the receiving rsync updates

"path/foo/file" using the existing path elements, which means

that the file ends up being created in "path/bar". Another way

to accomplish this link preservation is to use the

--keep-dirlinks option (which will also affect symlinks to

directories in the rest of the transfer).

In a similar but opposite scenario, if the transfer of

"path/foo/file" is requested and "path/foo" is a symlink on the

sending side, running without --no-implied-dirs would cause

rsync to transform "path/foo" on the receiving side into an

identical symlink, and then attempt to transfer "path/foo/file",

which might fail if the duplicated symlink did not point to a

directory on the receiving side. Another way to avoid this

sending of a symlink as an implied directory is to use

--copy-unsafe-links, or --copy-dirlinks (both of which also

affect symlinks in the rest of the transfer -- see their

descriptions for full details).

-b, --backup

With this option, preexisting destination files are renamed as

each file is transferred or deleted. You can control where the

backup file goes and what (if any) suffix gets appended using

the --backup-dir and --suffix options.

Note that if you don't specify --backup-dir, (1) the

--omit-dir-times option will be implied, and (2) if --delete is

also in effect (without --delete-excluded), rsync will add a

"protect" filter-rule for the backup suffix to the end of all

your existing excludes (e.g. -f "P *~"). This will prevent pre-

viously backed-up files from being deleted. Note that if you

are supplying your own filter rules, you may need to manually

insert your own exclude/protect rule somewhere higher up in the

list so that it has a high enough priority to be effective

(e.g., if your rules specify a trailing inclusion/exclusion of

'*', the auto-added rule would never be reached).

--backup-dir=DIR

In combination with the --backup option, this tells rsync to

store all backups in the specified directory on the receiving

side. This can be used for incremental backups. You can addi-

tionally specify a backup suffix using the --suffix option (oth-

erwise the files backed up in the specified directory will keep

their original filenames).

--suffix=SUFFIX

This option allows you to override the default backup suffix

used with the --backup (-b) option. The default suffix is a ~ if

no --backup-dir was specified, otherwise it is an empty string.

-u, --update

This forces rsync to skip any files which exist on the destina-

tion and have a modified time that is newer than the source

file. (If an existing destination file has a modify time equal

to the source file's, it will be updated if the sizes are dif-

ferent.)

In the current implementation of --update, a difference of file

format between the sender and receiver is always considered to

be important enough for an update, no matter what date is on the

objects. In other words, if the source has a directory or a

symlink where the destination has a file, the transfer would

occur regardless of the timestamps. This might change in the

future (feel free to comment on this on the mailing list if you

have an opinion).

--inplace

This causes rsync not to create a new copy of the file and then

move it into place. Instead rsync will overwrite the existing

file, meaning that the rsync algorithm can't accomplish the full

amount of network reduction it might be able to otherwise (since

it does not yet try to sort data matches). One exception to

this is if you combine the option with --backup, since rsync is

smart enough to use the backup file as the basis file for the

transfer.

This option is useful for transfer of large files with block-

based changes or appended data, and also on systems that are

disk bound, not network bound.

The option implies --partial (since an interrupted transfer does

not delete the file), but conflicts with --partial-dir and

--delay-updates. Prior to rsync 2.6.4 --inplace was also incom-

patible with --compare-dest and --link-dest.

WARNING: The file's data will be in an inconsistent state during

the transfer (and possibly afterward if the transfer gets inter-

rupted), so you should not use this option to update files that

are in use. Also note that rsync will be unable to update a

file in-place that is not writable by the receiving user.

--append

This causes rsync to update a file by appending data onto the

end of the file, which presumes that the data that already

exists on the receiving side is identical with the start of the

file on the sending side. If that is not true, the file will

fail the checksum test, and the resend will do a normal

--inplace update to correct the mismatched data. Only files on

the receiving side that are shorter than the corresponding file

on the sending side (as well as new files) are sent. Implies

--inplace, but does not conflict with --sparse (though the

--sparse option will be auto-disabled if a resend of the

already-existing data is required).

-d, --dirs

Tell the sending side to include any directories that are

encountered. Unlike --recursive, a directory's contents are not

copied unless the directory name specified is "." or ends with a

trailing slash (e.g. ".", "dir/.", "dir/", etc.). Without this

option or the --recursive option, rsync will skip all directo-

ries it encounters (and output a message to that effect for each

one). If you specify both --dirs and --recursive, --recursive

takes precedence.

-l, --links

When symlinks are encountered, recreate the symlink on the des-

tination.

-L, --copy-links

When symlinks are encountered, the item that they point to (the

referent) is copied, rather than the symlink. In older versions

of rsync, this option also had the side-effect of telling the

receiving side to follow symlinks, such as symlinks to directo-

ries. In a modern rsync such as this one, you'll need to spec-

ify --keep-dirlinks (-K) to get this extra behavior. The only

exception is when sending files to an rsync that is too old to

understand -K -- in that case, the -L option will still have the

side-effect of -K on that older receiving rsync.

--copy-unsafe-links

This tells rsync to copy the referent of symbolic links that

point outside the copied tree. Absolute symlinks are also

treated like ordinary files, and so are any symlinks in the

source path itself when --relative is used. This option has no

additional effect if --copy-links was also specified.

--safe-links

This tells rsync to ignore any symbolic links which point out-

side the copied tree. All absolute symlinks are also ignored.

Using this option in conjunction with --relative may give unex-

pected results.

-K, --copy-dirlinks

This option causes the sending side to treat a symlink to a

directory as though it were a real directory. This is useful if

you don't want symlinks to non-directories to be affected, as

they would be using --copy-links.

Without this option, if the sending side has replaced a direc-

tory with a symlink to a directory, the receiving side will

delete anything that is in the way of the new symlink, including

a directory hierarchy (as long as --force or --delete is in

effect).

See also --keep-dirlinks for an analogous option for the receiv-

ing side.

-K, --keep-dirlinks

This option causes the receiving side to treat a symlink to a

directory as though it were a real directory, but only if it

matches a real directory from the sender. Without this option,

the receiver's symlink would be deleted and replaced with a real

directory.

For example, suppose you transfer a directory "foo" that con-

tains a file "file", but "foo" is a symlink to directory "bar"

on the receiver. Without --keep-dirlinks, the receiver deletes

symlink "foo", recreates it as a directory, and receives the

file into the new directory. With --keep-dirlinks, the receiver

keeps the symlink and "file" ends up in "bar".

See also --copy-dirlinks for an analogous option for the sending

side.

-H, --hard-links

This tells rsync to look for hard-linked files in the transfer

and link together the corresponding files on the receiving side.

Without this option, hard-linked files in the transfer are

treated as though they were separate files.

Note that rsync can only detect hard links if both parts of the

link are in the list of files being sent.

-p, --perms

This option causes the receiving rsync to set the destination

permissions to be the same as the source permissions. (See also

the --chmod option for a way to modify what rsync considers to

be the source permissions.)

When this option is off, permissions are set as follows:

o Existing files (including updated files) retain their

existing permissions, though the --executability option

might change just the execute permission for the file.

o New files get their "normal" permission bits set to the

source file's permissions masked with the receiving end's

umask setting, and their special permission bits disabled

except in the case where a new directory inherits a set-

gid bit from its parent directory.

Thus, when --perms and --executability are both disabled,

rsync's behavior is the same as that of other file-copy utili-

ties, such as cp(1) and tar(1).

In summary: to give destination files (both old and new) the

source permissions, use --perms. To give new files the destina-

tion-default permissions (while leaving existing files

unchanged), make sure that the --perms option is off and use

--chmod=ugo=rwX (which ensures that all non-masked bits get

enabled). If you'd care to make this latter behavior easier to

type, you could define a popt alias for it, such as putting this

line in the file ~/.popt (this defines the -s option, and

includes --no-g to use the default group of the destination

dir):

rsync alias -s --no-p --no-g --chmod=ugo=rwX

You could then use this new option in a command such as this

one:

rsync -asv src/ dest/

(Caveat: make sure that -a does not follow -s, or it will re-

enable the "--no-*" options.)

The preservation of the destination's setgid bit on newly-cre-

ated directories when --perms is off was added in rsync 2.6.7.

Older rsync versions erroneously preserved the three special

permission bits for newly-created files when --perms was off,

while overriding the destination's setgid bit setting on a

newly-created directory. (Keep in mind that it is the version

of the receiving rsync that affects this behavior.)

--executability

This option causes rsync to preserve the executability (or non-

executability) of regular files when --perms is not enabled. A

regular file is considered to be executable if at least one 'x'

is turned on in its permissions. When an existing destination

file's executability differs from that of the corresponding

source file, rsync modifies the destination file's permissions

as follows:

o To make a file non-executable, rsync turns off all its

'x' permissions.

o To make a file executable, rsync turns on each 'x' per-

mission that has a corresponding 'r' permission enabled.

If --perms is enabled, this option is ignored.

--chmod

This option tells rsync to apply one or more comma-separated

"chmod" strings to the permission of the files in the transfer.

The resulting value is treated as though it was the permissions

that the sending side supplied for the file, which means that

this option can seem to have no effect on existing files if

--perms is not enabled.

In addition to the normal parsing rules specified in the

chmod(1) manpage, you can specify an item that should only apply

to a directory by prefixing it with a 'D', or specify an item

that should only apply to a file by prefixing it with a 'F'.

For example:

--chmod=Dg+s,ug+w,Fo-w,+X

It is also legal to specify multiple --chmod options, as each

additional option is just appended to the list of changes to

make.

See the --perms and --executability options for how the result-

ing permission value can be applied to the files in the trans-

fer.

-o, --owner

This option causes rsync to set the owner of the destination

file to be the same as the source file, but only if the receiv-

ing rsync is being run as the super-user (see also the --super

option to force rsync to attempt super-user activities). With-

out this option, the owner is set to the invoking user on the

receiving side.

The preservation of ownership will associate matching names by

default, but may fall back to using the ID number in some cir-

cumstances (see also the --numeric-ids option for a full discus-

sion).

-g, --group

This option causes rsync to set the group of the destination

file to be the same as the source file. If the receiving pro-

gram is not running as the super-user (or if --no-super was

specified), only groups that the invoking user on the receiving

side is a member of will be preserved. Without this option, the

group is set to the default group of the invoking user on the

receiving side.

The preservation of group information will associate matching

names by default, but may fall back to using the ID number in

some circumstances (see also the --numeric-ids option for a full

discussion).

--devices

This option causes rsync to transfer character and block device

files to the remote system to recreate these devices. This

option has no effect if the receiving rsync is not run as the

super-user and --super is not specified.

--specials

This option causes rsync to transfer special files such as named

sockets and fifos.

-D The -D option is equivalent to --devices --specials.

-t, --times

This tells rsync to transfer modification times along with the

files and update them on the remote system. Note that if this

option is not used, the optimization that excludes files that

have not been modified cannot be effective; in other words, a

missing -t or -a will cause the next transfer to behave as if it

used -I, causing all files to be updated (though the rsync algo-

rithm will make the update fairly efficient if the files haven't

actually changed, you're much better off using -t).

-O, --omit-dir-times

This tells rsync to omit directories when it is preserving modi-

fication times (see --times). If NFS is sharing the directories

on the receiving side, it is a good idea to use -O. This option

is inferred if you use --backup without --backup-dir.

--super

This tells the receiving side to attempt super-user activities

even if the receiving rsync wasn't run by the super-user. These

activities include: preserving users via the --owner option,

preserving all groups (not just the current user's groups) via

the --groups option, and copying devices via the --devices

option. This is useful for systems that allow such activities

without being the super-user, and also for ensuring that you

will get errors if the receiving side isn't being running as the

super-user. To turn off super-user activities, the super-user

can use --no-super.

-S, --sparse

Try to handle sparse files efficiently so they take up less

space on the destination. Conflicts with --inplace because it's

not possible to overwrite data in a sparse fashion.

NOTE: Don't use this option when the destination is a Solaris

"tmpfs" filesystem. It doesn't seem to handle seeks over null

regions correctly and ends up corrupting the files.

-n, --dry-run

This tells rsync to not do any file transfers, instead it will

just report the actions it would have taken.

-W, --whole-file

With this option the incremental rsync algorithm is not used and

the whole file is sent as-is instead. The transfer may be

faster if this option is used when the bandwidth between the

source and destination machines is higher than the bandwidth to

disk (especially when the "disk" is actually a networked

filesystem). This is the default when both the source and des-

tination are specified as local paths.

-x, --one-file-system

This tells rsync to avoid crossing a filesystem boundary when

recursing. This does not limit the user's ability to specify

items to copy from multiple filesystems, just rsync's recursion

through the hierarchy of each directory that the user specified,

and also the analogous recursion on the receiving side during

deletion. Also keep in mind that rsync treats a "bind" mount to

the same device as being on the same filesystem.

If this option is repeated, rsync omits all mount-point directo-

ries from the copy. Otherwise, it includes an empty directory

at each mount-point it encounters (using the attributes of the

mounted directory because those of the underlying mount-point

directory are inaccessible).

If rsync has been told to collapse symlinks (via --copy-links or

--copy-unsafe-links), a symlink to a directory on another device

is treated like a mount-point. Symlinks to non-directories are

unaffected by this option.

--existing, --ignore-non-existing

This tells rsync to skip creating files (including directories)

that do not exist yet on the destination. If this option is

combined with the --ignore-existing option, no files will be

updated (which can be useful if all you want to do is to delete

extraneous files).

--ignore-existing

This tells rsync to skip updating files that already exist on

the destination (this does not ignore existing directores, or

nothing would get done). See also --existing.

--remove-source-files

This tells rsync to remove from the sending side the files

(meaning non-directories) that are a part of the transfer and

have been successfully duplicated on the receiving side.

--delete

This tells rsync to delete extraneous files from the receiving

side (ones that aren't on the sending side), but only for the

directories that are being synchronized. You must have asked

rsync to send the whole directory (e.g. "dir" or "dir/") without

using a wildcard for the directory's contents (e.g. "dir/*")

since the wildcard is expanded by the shell and rsync thus gets

a request to transfer individual files, not the files' parent

directory. Files that are excluded from transfer are also

excluded from being deleted unless you use the --delete-excluded

option or mark the rules as only matching on the sending side

(see the include/exclude modifiers in the FILTER RULES section).

Prior to rsync 2.6.7, this option would have no effect unless

--recursive was in effect. Beginning with 2.6.7, deletions will

also occur when --dirs (-d) is in effect, but only for directo-

ries whose contents are being copied.

This option can be dangerous if used incorrectly! It is a very

good idea to run first using the --dry-run option (-n) to see

what files would be deleted to make sure important files aren't

listed.

If the sending side detects any I/O errors, then the deletion of

any files at the destination will be automatically disabled.

This is to prevent temporary filesystem failures (such as NFS

errors) on the sending side causing a massive deletion of files

on the destination. You can override this with the

--ignore-errors option.

The --delete option may be combined with one of the

--delete-WHEN options without conflict, as well as

--delete-excluded. However, if none of the --delete-WHEN

options are specified, rsync will currently choose the

--delete-before algorithm. A future version may change this to

choose the --delete-during algorithm. See also --delete-after.

--delete-before

Request that the file-deletions on the receiving side be done

before the transfer starts. This is the default if --delete or

--delete-excluded is specified without one of the --delete-WHEN

options. See --delete (which is implied) for more details on

file-deletion.

Deleting before the transfer is helpful if the filesystem is

tight for space and removing extraneous files would help to make

the transfer possible. However, it does introduce a delay

before the start of the transfer, and this delay might cause the

transfer to timeout (if --timeout was specified).

--delete-during, --del

Request that the file-deletions on the receiving side be done

incrementally as the transfer happens. This is a faster method

than choosing the before- or after-transfer algorithm, but it is

only supported beginning with rsync version 2.6.4. See --delete

(which is implied) for more details on file-deletion.

--delete-after

Request that the file-deletions on the receiving side be done

after the transfer has completed. This is useful if you are

sending new per-directory merge files as a part of the transfer

and you want their exclusions to take effect for the delete

phase of the current transfer. See --delete (which is implied)

for more details on file-deletion.

--delete-excluded

In addition to deleting the files on the receiving side that are

not on the sending side, this tells rsync to also delete any

files on the receiving side that are excluded (see --exclude).

See the FILTER RULES section for a way to make individual exclu-

sions behave this way on the receiver, and for a way to protect

files from --delete-excluded. See --delete (which is implied)

for more details on file-deletion.

--ignore-errors

Tells --delete to go ahead and delete files even when there are

I/O errors.

--force

This option tells rsync to delete a non-empty directory when it

is to be replaced by a non-directory. This is only relevant if

deletions are not active (see --delete for details).

Note for older rsync versions: --force used to still be required

when using --delete-after, and it used to be non-functional

unless the --recursive option was also enabled.

--max-delete=NUM

This tells rsync not to delete more than NUM files or directo-

ries (NUM must be non-zero). This is useful when mirroring very

large trees to prevent disasters.

--max-size=SIZE

This tells rsync to avoid transferring any file that is larger

than the specified SIZE. The SIZE value can be suffixed with a

string to indicate a size multiplier, and may be a fractional

value (e.g. "--max-size=1.5m").

The suffixes are as follows: "K" (or "KiB") is a kibibyte

(1024), "M" (or "MiB") is a mebibyte (1024*1024), and "G" (or

"GiB") is a gibibyte (1024*1024*1024). If you want the multi-

plier to be 1000 instead of 1024, use "KB", "MB", or "GB".

(Note: lower-case is also accepted for all values.) Finally, if

the suffix ends in either "+1" or "-1", the value will be offset

by one byte in the indicated direction.

Examples: --max-size=1.5mb-1 is 1499999 bytes, and

--max-size=2g+1 is 2147483649 bytes.

--min-size=SIZE

This tells rsync to avoid transferring any file that is smaller

than the specified SIZE, which can help in not transferring

small, junk files. See the --max-size option for a description

of SIZE.

-B, --block-size=BLOCKSIZE

This forces the block size used in the rsync algorithm to a

fixed value. It is normally selected based on the size of each

file being updated. See the technical report for details.

-e, --rsh=COMMAND

This option allows you to choose an alternative remote shell

program to use for communication between the local and remote

copies of rsync. Typically, rsync is configured to use ssh by

default, but you may prefer to use rsh on a local network.

If this option is used with [user@]host::module/path, then the

remote shell COMMAND will be used to run an rsync daemon on the

remote host, and all data will be transmitted through that

remote shell connection, rather than through a direct socket

connection to a running rsync daemon on the remote host. See

the section "USING RSYNC-DAEMON FEATURES VIA A REMOTE-SHELL CON-

NECTION" above.

Command-line arguments are permitted in COMMAND provided that

COMMAND is presented to rsync as a single argument. You must

use spaces (not tabs or other whitespace) to separate the com-

mand and args from each other, and you can use single- and/or

double-quotes to preserve spaces in an argument (but not back-

slashes). Note that doubling a single-quote inside a single-

quoted string gives you a single-quote; likewise for double-

quotes (though you need to pay attention to which quotes your

shell is parsing and which quotes rsync is parsing). Some exam-

ples:

-e 'ssh -p 2234'

-e 'ssh -o "ProxyCommand nohup ssh firewall nc -w1 %h %p"'

(Note that ssh users can alternately customize site-specific

connect options in their .ssh/config file.)

You can also choose the remote shell program using the RSYNC_RSH

environment variable, which accepts the same range of values as

-e.

See also the --blocking-io option which is affected by this

option.

--rsync-path=PROGRAM

Use this to specify what program is to be run on the remote

machine to start-up rsync. Often used when rsync is not in the

default remote-shell's path (e.g.

--rsync-path=/usr/local/bin/rsync). Note that PROGRAM is run

with the help of a shell, so it can be any program, script, or

command sequence you'd care to run, so long as it does not cor-

rupt the standard-in & standard-out that rsync is using to com-

municate.

One tricky example is to set a different default directory on

the remote machine for use with the --relative option. For

instance:

rsync -avR --rsync-path="cd /a/b && rsync" hst:c/d /e/

-C, --cvs-exclude

This is a useful shorthand for excluding a broad range of files

that you often don't want to transfer between systems. It uses

the same algorithm that CVS uses to determine if a file should

be ignored.

The exclude list is initialized to:

RCS SCCS CVS CVS.adm RCSLOG cvslog.* tags TAGS

.make.state .nse_depinfo *~ #* .#* ,* _* * *.old *.bak

*.BAK *.orig *.rej .del-* *.a *.olb *.o *.obj *.so *.exe

*.Z *.elc *.ln core .svn/

then files listed in a $HOME/.cvsignore are added to the list

and any files listed in the CVSIGNORE environment variable (all

cvsignore names are delimited by whitespace).

Finally, any file is ignored if it is in the same directory as a

.cvsignore file and matches one of the patterns listed therein.

Unlike rsync's filter/exclude files, these patterns are split on

whitespace. See the cvs(1) manual for more information.

If you're combining -C with your own --filter rules, you should

note that these CVS excludes are appended at the end of your own

rules, regardless of where the -C was placed on the command-

line. This makes them a lower priority than any rules you spec-

ified explicitly. If you want to control where these CVS

excludes get inserted into your filter rules, you should omit

the -C as a command-line option and use a combination of --fil-

ter=:C and --filter=-C (either on your command-line or by

putting the ":C" and "-C" rules into a filter file with your

other rules). The first option turns on the per-directory scan-

ning for the .cvsignore file. The second option does a one-time

import of the CVS excludes mentioned above.

-f, --filter=RULE

This option allows you to add rules to selectively exclude cer-

tain files from the list of files to be transferred. This is

most useful in combination with a recursive transfer.

You may use as many --filter options on the command line as you

like to build up the list of files to exclude.

See the FILTER RULES section for detailed information on this

option.

-F The -F option is a shorthand for adding two --filter rules to

your command. The first time it is used is a shorthand for this

rule:

--filter='dir-merge /.rsync-filter'

This tells rsync to look for per-directory .rsync-filter files

that have been sprinkled through the hierarchy and use their

rules to filter the files in the transfer. If -F is repeated,

it is a shorthand for this rule:

--filter='exclude .rsync-filter'

This filters out the .rsync-filter files themselves from the

transfer.

See the FILTER RULES section for detailed information on how

these options work.

--exclude=PATTERN

This option is a simplified form of the --filter option that

defaults to an exclude rule and does not allow the full rule-

parsing syntax of normal filter rules.

See the FILTER RULES section for detailed information on this

option.

--exclude-from=FILE

This option is related to the --exclude option, but it specifies

a FILE that contains exclude patterns (one per line). Blank

lines in the file and lines starting with ';' or '#' are

ignored. If FILE is -, the list will be read from standard

input.

--include=PATTERN

This option is a simplified form of the --filter option that

defaults to an include rule and does not allow the full rule-

parsing syntax of normal filter rules.

See the FILTER RULES section for detailed information on this

option.

--include-from=FILE

This option is related to the --include option, but it specifies

a FILE that contains include patterns (one per line). Blank

lines in the file and lines starting with ';' or '#' are

ignored. If FILE is -, the list will be read from standard

input.

--files-from=FILE

Using this option allows you to specify the exact list of files

to transfer (as read from the specified FILE or - for standard

input). It also tweaks the default behavior of rsync to make

transferring just the specified files and directories easier:

o The --relative (-R) option is implied, which preserves

the path information that is specified for each item in

the file (use --no-relative or --no-R if you want to turn

that off).

o The --dirs (-d) option is implied, which will create

directories specified in the list on the destination

rather than noisily skipping them (use --no-dirs or

--no-d if you want to turn that off).

o The --archive (-a) option's behavior does not imply

--recursive (-r), so specify it explicitly, if you want

it.

o These side-effects change the default state of rsync, so

the position of the --files-from option on the command-

line has no bearing on how other options are parsed (e.g.

-a works the same before or after --files-from, as does

--no-R and all other options).

The file names that are read from the FILE are all relative to

the source dir -- any leading slashes are removed and no ".."

references are allowed to go higher than the source dir. For

example, take this command:

rsync -a --files-from=/tmp/foo /usr remote:/backup

If /tmp/foo contains the string "bin" (or even "/bin"), the

/usr/bin directory will be created as /backup/bin on the remote

host. If it contains "bin/" (note the trailing slash), the

immediate contents of the directory would also be sent (without

needing to be explicitly mentioned in the file -- this began in

version 2.6.4). In both cases, if the -r option was enabled,

that dir's entire hierarchy would also be transferred (keep in

mind that -r needs to be specified explicitly with --files-from,

since it is not implied by -a). Also note that the effect of

the (enabled by default) --relative option is to duplicate only

the path info that is read from the file -- it does not force

the duplication of the source-spec path (/usr in this case).

In addition, the --files-from file can be read from the remote

host instead of the local host if you specify a "host:" in front

of the file (the host must match one end of the transfer). As a

short-cut, you can specify just a prefix of ":" to mean "use the

remote end of the transfer". For example:

rsync -a --files-from=:/path/file-list src:/ /tmp/copy

This would copy all the files specified in the /path/file-list

file that was located on the remote "src" host.

-0, --from0

This tells rsync that the rules/filenames it reads from a file

are terminated by a null ('\0') character, not a NL, CR, or

CR+LF. This affects --exclude-from, --include-from,

--files-from, and any merged files specified in a --filter rule.

It does not affect --cvs-exclude (since all names read from a

.cvsignore file are split on whitespace).

-T, --temp-dir=DIR

This option instructs rsync to use DIR as a scratch directory

when creating temporary copies of the files transferred on the

receiving side. The default behavior is to create each tempo-

rary file in the same directory as the associated destination

file.

This option is most often used when the receiving disk partition

does not have enough free space to hold a copy of the largest

file in the transfer. In this case (i.e. when the scratch

directory in on a different disk partition), rsync will not be

able to rename each received temporary file over the top of the

associated destination file, but instead must copy it into

place. Rsync does this by copying the file over the top of the

destination file, which means that the destination file will

contain truncated data during this copy. If this were not done

this way (even if the destination file were first removed, the

data locally copied to a temporary file in the destination

directory, and then renamed into place) it would be possible for

the old file to continue taking up disk space (if someone had it

open), and thus there might not be enough room to fit the new

version on the disk at the same time.

If you are using this option for reasons other than a shortage

of disk space, you may wish to combine it with the

--delay-updates option, which will ensure that all copied files

get put into subdirectories in the destination hierarchy, await-

ing the end of the transfer. If you don't have enough room to

duplicate all the arriving files on the destination partition,

another way to tell rsync that you aren't overly concerned about

disk space is to use the --partial-dir option with a relative

path; because this tells rsync that it is OK to stash off a copy

of a single file in a subdir in the destination hierarchy, rsync

will use the partial-dir as a staging area to bring over the

copied file, and then rename it into place from there. (Specify-

ing a --partial-dir with an absolute path does not have this

side-effect.)

-y, --fuzzy

This option tells rsync that it should look for a basis file for

any destination file that is missing. The current algorithm

looks in the same directory as the destination file for either a

file that has an identical size and modified-time, or a simi-

larly-named file. If found, rsync uses the fuzzy basis file to

try to speed up the transfer.

Note that the use of the --delete option might get rid of any

potential fuzzy-match files, so either use --delete-after or

specify some filename exclusions if you need to prevent this.

--compare-dest=DIR

This option instructs rsync to use DIR on the destination

machine as an additional hierarchy to compare destination files

against doing transfers (if the files are missing in the desti-

nation directory). If a file is found in DIR that is identical

to the sender's file, the file will NOT be transferred to the

destination directory. This is useful for creating a sparse

backup of just files that have changed from an earlier backup.

Beginning in version 2.6.4, multiple --compare-dest directories

may be provided, which will cause rsync to search the list in

the order specified for an exact match. If a match is found

that differs only in attributes, a local copy is made and the

attributes updated. If a match is not found, a basis file from

one of the DIRs will be selected to try to speed up the trans-

fer.

If DIR is a relative path, it is relative to the destination

directory. See also --copy-dest and --link-dest.

--copy-dest=DIR

This option behaves like --compare-dest, but rsync will also

copy unchanged files found in DIR to the destination directory

using a local copy. This is useful for doing transfers to a new

destination while leaving existing files intact, and then doing

a flash-cutover when all files have been successfully trans-

ferred.

Multiple --copy-dest directories may be provided, which will

cause rsync to search the list in the order specified for an

unchanged file. If a match is not found, a basis file from one

of the DIRs will be selected to try to speed up the transfer.

If DIR is a relative path, it is relative to the destination

directory. See also --compare-dest and --link-dest.

--link-dest=DIR

This option behaves like --copy-dest, but unchanged files are

hard linked from DIR to the destination directory. The files

must be identical in all preserved attributes (e.g. permissions,

possibly ownership) in order for the files to be linked

together. An example:

rsync -av --link-dest=$PWD/prior_dir host:src_dir/ new_dir/

Beginning in version 2.6.4, multiple --link-dest directories may

be provided, which will cause rsync to search the list in the

order specified for an exact match. If a match is found that

differs only in attributes, a local copy is made and the

attributes updated. If a match is not found, a basis file from

one of the DIRs will be selected to try to speed up the trans-

fer.

Note that if you combine this option with --ignore-times, rsync

will not link any files together because it only links identical

files together as a substitute for transferring the file, never

as an additional check after the file is updated.

If DIR is a relative path, it is relative to the destination

directory. See also --compare-dest and --copy-dest.

Note that rsync versions prior to 2.6.1 had a bug that could

prevent --link-dest from working properly for a non-super-user

when -o was specified (or implied by -a). You can work-around

this bug by avoiding the -o option when sending to an old rsync.

-z, --compress

With this option, rsync compresses the file data as it is sent

to the destination machine, which reduces the amount of data

being transmitted -- something that is useful over a slow con-

nection.

Note that this option typically achieves better compression

ratios than can be achieved by using a compressing remote shell

or a compressing transport because it takes advantage of the

implicit information in the matching data blocks that are not

explicitly sent over the connection.

--compress-level=NUM

Explicitly set the compression level to use (see --compress)

instead of letting it default. If NUM is non-zero, the --com-

press option is implied.

--numeric-ids

With this option rsync will transfer numeric group and user IDs

rather than using user and group names and mapping them at both

ends.

By default rsync will use the username and groupname to deter-

mine what ownership to give files. The special uid 0 and the

special group 0 are never mapped via user/group names even if

the --numeric-ids option is not specified.

If a user or group has no name on the source system or it has no

match on the destination system, then the numeric ID from the

source system is used instead. See also the comments on the

"use chroot" setting in the rsyncd.conf manpage for information

on how the chroot setting affects rsync's ability to look up the

names of the users and groups and what you can do about it.

--timeout=TIMEOUT

This option allows you to set a maximum I/O timeout in seconds.

If no data is transferred for the specified time then rsync will

exit. The default is 0, which means no timeout.

--address

By default rsync will bind to the wildcard address when connect-

ing to an rsync daemon. The --address option allows you to

specify a specific IP address (or hostname) to bind to. See

also this option in the --daemon mode section.

--port=PORT

This specifies an alternate TCP port number to use rather than

the default of 873. This is only needed if you are using the

double-colon (::) syntax to connect with an rsync daemon (since

the URL syntax has a way to specify the port as a part of the

URL). See also this option in the --daemon mode section.

--sockopts

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. This only affects direct socket

connections to a remote rsync daemon. This option also exists

in the --daemon mode section.

--blocking-io

This tells rsync to use blocking I/O when launching a remote

shell transport. If the remote shell is either rsh or remsh,

rsync defaults to using blocking I/O, otherwise it defaults to

using non-blocking I/O. (Note that ssh prefers non-blocking

I/O.)

-i, --itemize-changes

Requests a simple itemized list of the changes that are being

made to each file, including attribute changes. This is exactly

the same as specifying --out-format='%i %n%L'. If you repeat

the option, unchanged files will also be output, but only if the

receiving rsync is at least version 2.6.7 (you can use -vv with

older versions of rsync, but that also turns on the output of

other verbose messages).

The "%i" escape has a cryptic output that is 9 letters long.

The general format is like the string YXcstpogz, where Y is

replaced by the type of update being done, X is replaced by the

file-type, and the other letters represent attributes that may

be output if they are being modified.

The update types that replace the Y are as follows:

o A < means that a file is being transferred to the remote

host (sent).

o A > means that a file is being transferred to the local

host (received).

o A c means that a local change/creation is occurring for

the item (such as the creation of a directory or the

changing of a symlink, etc.).

o A h means that the item is a hard link to another item

(requires --hard-links).

o A . means that the item is not being updated (though it

might have attributes that are being modified).

The file-types that replace the X are: f for a file, a d for a

directory, an L for a symlink, a D for a device, and a S for a

special file (e.g. named sockets and fifos).

The other letters in the string above are the actual letters

that will be output if the associated attribute for the item is

being updated or a "." for no change. Three exceptions to this

are: (1) a newly created item replaces each letter with a "+",

(2) an identical item replaces the dots with spaces, and (3) an

unknown attribute replaces each letter with a "?" (this can hap-

pen when talking to an older rsync).

The attribute that is associated with each letter is as follows:

o A c means the checksum of the file is different and will

be updated by the file transfer (requires --checksum).

o A s means the size of the file is different and will be

updated by the file transfer.

o A t means the modification time is different and is being

updated to the sender's value (requires --times). An

alternate value of T means that the time will be set to

the transfer time, which happens anytime a symlink is

transferred, or when a file or device is transferred

without --times.

o A p means the permissions are different and are being

updated to the sender's value (requires --perms).

o An o means the owner is different and is being updated to

the sender's value (requires --owner and super-user priv-

ileges).

o A g means the group is different and is being updated to

the sender's value (requires --group and the authority to

set the group).

o The z slot is reserved for future use.

One other output is possible: when deleting files, the "%i"

will output the string "*deleting" for each item that is being

removed (assuming that you are talking to a recent enough rsync

that it logs deletions instead of outputting them as a verbose

message).

--out-format=FORMAT

This allows you to specify exactly what the rsync client outputs

to the user on a per-update basis. The format is a text string

containing embedded single-character escape sequences prefixed

with a percent (%) character. For a list of the possible escape

characters, see the "log format" setting in the rsyncd.conf man-

page.

Specifying this option will mention each file, dir, etc. that

gets updated in a significant way (a transferred file, a recre-

ated symlink/device, or a touched directory). In addition, if

the itemize-changes escape (%i) is included in the string, the

logging of names increases to mention any item that is changed

in any way (as long as the receiving side is at least 2.6.4).

See the --itemize-changes option for a description of the output

of "%i".

The --verbose option implies a format of "%n%L", but you can use

--out-format without --verbose if you like, or you can override

the format of its per-file output using this option.

Rsync will output the out-format string prior to a file's trans-

fer unless one of the transfer-statistic escapes is requested,

in which case the logging is done at the end of the file's

transfer. When this late logging is in effect and --progress is

also specified, rsync will also output the name of the file

being transferred prior to its progress information (followed,

of course, by the out-format output).

--log-file=FILE

This option causes rsync to log what it is doing to a file.

This is similar to the logging that a daemon does, but can be

requested for the client side and/or the server side of a non-

daemon transfer. If specified as a client option, transfer log-

ging will be enabled with a default format of "%i %n%L". See

the --log-file-format option if you wish to override this.

Here's a example command that requests the remote side to log

what is happening:

rsync -av --rsync-path="rsync --log-file=/tmp/rlog" src/ dest/

This is very useful if you need to debug why a connection is

closing unexpectedly.

--log-file-format=FORMAT

This allows you to specify exactly what per-update logging is

put into the file specified by the --log-file option (which must

also be specified for this option to have any effect). If you

specify an empty string, updated files will not be mentioned in

the log file. For a list of the possible escape characters, see

the "log format" setting in the rsyncd.conf manpage.

--stats

This tells rsync to print a verbose set of statistics on the

file transfer, allowing you to tell how effective the rsync

algorithm is for your data.

The current statistics are as follows:

o Number of files is the count of all "files" (in the

generic sense), which includes directories, symlinks,

etc.

o Number of files transferred is the count of normal files

that were updated via the rsync algorithm, which does not

include created dirs, symlinks, etc.

o Total file size is the total sum of all file sizes in the

transfer. This does not count any size for directories

or special files, but does include the size of symlinks.

o Total transferred file size is the total sum of all files

sizes for just the transferred files.

o Literal data is how much unmatched file-update data we

had to send to the receiver for it to recreate the

updated files.

o Matched data is how much data the receiver got locally

when recreating the updated files.

o File list size is how big the file-list data was when the

sender sent it to the receiver. This is smaller than the

in-memory size for the file list due to some compressing

of duplicated data when rsync sends the list.

o File list generation time is the number of seconds that

the sender spent creating the file list. This requires a

modern rsync on the sending side for this to be present.

o File list transfer time is the number of seconds that the

sender spent sending the file list to the receiver.

o Total bytes sent is the count of all the bytes that rsync

sent from the client side to the server side.

o Total bytes received is the count of all non-message

bytes that rsync received by the client side from the

server side. "Non-message" bytes means that we don't

count the bytes for a verbose message that the server

sent to us, which makes the stats more consistent.

-8, --8-bit-output

This tells rsync to leave all high-bit characters unescaped in

the output instead of trying to test them to see if they're

valid in the current locale and escaping the invalid ones. All

control characters (but never tabs) are always escaped, regard-

less of this option's setting.

The escape idiom that started in 2.6.7 is to output a literal

backslash (\) and a hash (#), followed by exactly 3 octal dig-

its. For example, a newline would output as "\#012". A literal

backslash that is in a filename is not escaped unless it is fol-

lowed by a hash and 3 digits (0-9).

-h, --human-readable

Output numbers in a more human-readable format. This makes big

numbers output using larger units, with a K, M, or G suffix. If

this option was specified once, these units are K (1000), M

(1000*1000), and G (1000*1000*1000); if the option is repeated,

the units are powers of 1024 instead of 1000.

--partial

By default, rsync will delete any partially transferred file if

the transfer is interrupted. In some circumstances it is more

desirable to keep partially transferred files. Using the --par-

tial option tells rsync to keep the partial file which should

make a subsequent transfer of the rest of the file much faster.

--partial-dir=DIR

A better way to keep partial files than the --partial option is

to specify a DIR that will be used to hold the partial data

(instead of writing it out to the destination file). On the

next transfer, rsync will use a file found in this dir as data

to speed up the resumption of the transfer and then delete it

after it has served its purpose.

Note that if --whole-file is specified (or implied), any par-

tial-dir file that is found for a file that is being updated

will simply be removed (since rsync is sending files without

using the incremental rsync algorithm).

Rsync will create the DIR if it is missing (just the last dir --

not the whole path). This makes it easy to use a relative path

(such as "--partial-dir=.rsync-partial") to have rsync create

the partial-directory in the destination file's directory when

needed, and then remove it again when the partial file is

deleted.

If the partial-dir value is not an absolute path, rsync will add

an exclude rule at the end of all your existing excludes. This

will prevent the sending of any partial-dir files that may exist

on the sending side, and will also prevent the untimely deletion

of partial-dir items on the receiving side. An example: the

above --partial-dir option would add the equivalent of

"--exclude=.rsync-partial/" at the end of any other filter

rules.

If you are supplying your own exclude rules, you may need to add

your own exclude/hide/protect rule for the partial-dir because

(1) the auto-added rule may be ineffective at the end of your

other rules, or (2) you may wish to override rsync's exclude

choice. For instance, if you want to make rsync clean-up any

left-over partial-dirs that may be lying around, you should

specify --delete-after and add a "risk" filter rule, e.g. -f 'R

.rsync-partial/'. (Avoid using --delete-before or --delete-dur-

ing unless you don't need rsync to use any of the left-over par-

tial-dir data during the current run.)

IMPORTANT: the --partial-dir should not be writable by other

users or it is a security risk. E.g. AVOID "/tmp".

You can also set the partial-dir value the RSYNC_PARTIAL_DIR

environment variable. Setting this in the environment does not

force --partial to be enabled, but rather it affects where par-

tial files go when --partial is specified. For instance,

instead of using --partial-dir=.rsync-tmp along with --progress,

you could set RSYNC_PARTIAL_DIR=.rsync-tmp in your environment

and then just use the -P option to turn on the use of the

.rsync-tmp dir for partial transfers. The only times that the

--partial option does not look for this environment value are

(1) when --inplace was specified (since --inplace conflicts with

--partial-dir), and (2) when --delay-updates was specified (see

below).

For the purposes of the daemon-config's "refuse options" set-

ting, --partial-dir does not imply --partial. This is so that a

refusal of the --partial option can be used to disallow the

overwriting of destination files with a partial transfer, while

still allowing the safer idiom provided by --partial-dir.

--delay-updates

This option puts the temporary file from each updated file into

a holding directory until the end of the transfer, at which time

all the files are renamed into place in rapid succession. This

attempts to make the updating of the files a little more atomic.

By default the files are placed into a directory named ".~tmp~"

in each file's destination directory, but if you've specified

the --partial-dir option, that directory will be used instead.

See the comments in the --partial-dir section for a discussion

of how this ".~tmp~" dir will be excluded from the transfer, and

what you can do if you wnat rsync to cleanup old ".~tmp~" dirs

that might be lying around. Conflicts with --inplace and

--append.

This option uses more memory on the receiving side (one bit per

file transferred) and also requires enough free disk space on

the receiving side to hold an additional copy of all the updated

files. Note also that you should not use an absolute path to

--partial-dir unless (1) there is no chance of any of the files

in the transfer having the same name (since all the updated

files will be put into a single directory if the path is abso-

lute) and (2) there are no mount points in the hierarchy (since

the delayed updates will fail if they can't be renamed into

place).

See also the "atomic-rsync" perl script in the "support" subdir

for an update algorithm that is even more atomic (it uses

--link-dest and a parallel hierarchy of files).

-m, --prune-empty-dirs

This option tells the receiving rsync to get rid of empty direc-

tories from the file-list, including nested directories that

have no non-directory children. This is useful for avoiding the

creation of a bunch of useless directories when the sending

rsync is recursively scanning a hierarchy of files using

include/exclude/filter rules.

Because the file-list is actually being pruned, this option also

affects what directories get deleted when a delete is active.

However, keep in mind that excluded files and directories can

prevent existing items from being deleted (because an exclude

hides source files and protects destination files).

You can prevent the pruning of certain empty directories from

the file-list by using a global "protect" filter. For instance,

this option would ensure that the directory "emptydir" was kept

in the file-list:

--filter 'protect emptydir/'

Here's an example that copies all .pdf files in a hierarchy,

only creating the necessary destination directories to hold the

.pdf files, and ensures that any superfluous files and directo-

ries in the destination are removed (note the hide filter of

non-directories being used instead of an exclude):

rsync -avm --del --include='*.pdf' -f 'hide,! */' src/ dest

If you didn't want to remove superfluous destination files, the

more time-honored options of "--include='*/' --exclude='*'"

would work fine in place of the hide-filter (if that is more

natural to you).

--progress

This option tells rsync to print information showing the

progress of the transfer. This gives a bored user something to

watch. Implies --verbose if it wasn't already specified.

While rsync is transferring a regular file, it updates a

progress line that looks like this:

782448 63% 110.64kB/s 0:00:04

In this example, the receiver has reconstructed 782448 bytes or

63% of the sender's file, which is being reconstructed at a rate

of 110.64 kilobytes per second, and the transfer will finish in

4 seconds if the current rate is maintained until the end.

These statistics can be misleading if the incremental transfer

algorithm is in use. For example, if the sender's file consists

of the basis file followed by additional data, the reported rate

will probably drop dramatically when the receiver gets to the

literal data, and the transfer will probably take much longer to

finish than the receiver estimated as it was finishing the

matched part of the file.

When the file transfer finishes, rsync replaces the progress

line with a summary line that looks like this:

1238099 100% 146.38kB/s 0:00:08 (xfer#5, to-check=169/396)

In this example, the file was 1238099 bytes long in total, the

average rate of transfer for the whole file was 146.38 kilobytes

per second over the 8 seconds that it took to complete, it was

the 5th transfer of a regular file during the current rsync ses-

sion, and there are 169 more files for the receiver to check (to

see if they are up-to-date or not) remaining out of the 396

total files in the file-list.

-P The -P option is equivalent to --partial --progress. Its pur-

pose is to make it much easier to specify these two options for

a long transfer that may be interrupted.

--password-file

This option allows you to provide a password in a file for

accessing a remote rsync daemon. Note that this option is only

useful when accessing an rsync daemon using the built in trans-

port, not when using a remote shell as the transport. The file

must not be world readable. It should contain just the password

as a single line.

--list-only

This option will cause the source files to be listed instead of

transferred. This option is inferred if there is a single

source arg and no destination specified, so its main uses are:

(1) to turn a copy command that includes a destination arg into

a file-listing command, (2) to be able to specify more than one

local source arg (note: be sure to include the destination), or

(3) to avoid the automatically added "-r --exclude='/*/*'"

options that rsync usually uses as a compatibility kluge when

generating a non-recursive listing. Caution: keep in mind that

a source arg with a wild-card is expanded by the shell into mul-

tiple args, so it is never safe to try to list such an arg with-

out using this option. For example:

rsync -av --list-only foo* dest/

--bwlimit=KBPS

This option allows you to specify a maximum transfer rate in

kilobytes per second. This option is most effective when using

rsync with large files (several megabytes and up). Due to the

nature of rsync transfers, blocks of data are sent, then if

rsync determines the transfer was too fast, it will wait before

sending the next data block. The result is an average transfer

rate equaling the specified limit. A value of zero specifies no

limit.

--write-batch=FILE

Record a file that can later be applied to another identical

destination with --read-batch. See the "BATCH MODE" section for

details, and also the --only-write-batch option.

--only-write-batch=FILE

Works like --write-batch, except that no updates are made on the

destination system when creating the batch. This lets you

transport the changes to the destination system via some other

means and then apply the changes via --read-batch.

Note that you can feel free to write the batch directly to some

portable media: if this media fills to capacity before the end

of the transfer, you can just apply that partial transfer to the

destination and repeat the whole process to get the rest of the

changes (as long as you don't mind a partially updated destina-

tion system while the multi-update cycle is happening).

Also note that you only save bandwidth when pushing changes to a

remote system because this allows the batched data to be

diverted from the sender into the batch file without having to

flow over the wire to the receiver (when pulling, the sender is

remote, and thus can't write the batch).

--read-batch=FILE

Apply all of the changes stored in FILE, a file previously gen-

erated by --write-batch. If FILE is -, the batch data will be

read from standard input. See the "BATCH MODE" section for

details.

--protocol=NUM

Force an older protocol version to be used. This is useful for

creating a batch file that is compatible with an older version

of rsync. For instance, if rsync 2.6.4 is being used with the

--write-batch option, but rsync 2.6.3 is what will be used to

run the --read-batch option, you should use "--protocol=28" when

creating the batch file to force the older protocol version to

be used in the batch file (assuming you can't upgrade the rsync

on the reading system).

-4, --ipv4 or -6, --ipv6

Tells rsync to prefer IPv4/IPv6 when creating sockets. This

only affects sockets that rsync has direct control over, such as

the outgoing socket when directly contacting an rsync daemon.

See also these options in the --daemon mode section.

--checksum-seed=NUM

Set the MD4 checksum seed to the integer NUM. This 4 byte

checksum seed is included in each block and file MD4 checksum

calculation. By default the checksum seed is generated by the

server and defaults to the current time() . This option is used

to set a specific checksum seed, which is useful for applica-

tions that want repeatable block and file checksums, or in the

case where the user wants a more random checksum seed. Note

that setting NUM to 0 causes rsync to use the default of time()

for checksum seed.

-E, --extended-attributes

Apple specific option to copy extended attributes, resource

forks, and ACLs. Requires at least Mac OS X 10.4 or suitably

patched rsync.

--cache

Apple specific option to enable filesystem caching of rsync file

i/o Otherwise fcntl(F_NOCACHE) is used to limit memory growth.

DAEMON OPTIONS

The options allowed when starting an rsync daemon are as follows:

--daemon

This tells rsync that it is to run as a daemon. The daemon you

start running may be accessed using an rsync client using the

host::module or rsync://host/module/ syntax.

If standard input is a socket then rsync will assume that it is

being run via inetd, otherwise it will detach from the current

terminal and become a background daemon. The daemon will read

the config file (rsyncd.conf) on each connect made by a client

and respond to requests accordingly. See the rsyncd.conf(5) man

page for more details.

--address

By default rsync will bind to the wildcard address when run as a

daemon with the --daemon option. The --address option allows

you to specify a specific IP address (or hostname) to bind to.

This makes virtual hosting possible in conjunction with the

--config option. See also the "address" global option in the

rsyncd.conf manpage.

--bwlimit=KBPS

This option allows you to specify a maximum transfer rate in

kilobytes per second for the data the daemon sends. The client

can still specify a smaller --bwlimit value, but their requested

value will be rounded down if they try to exceed it. See the

client version of this option (above) for some extra details.

--config=FILE

This specifies an alternate config file than the default. This

is only relevant when --daemon is specified. The default is

/etc/rsyncd.conf unless the daemon is running over a remote

shell program and the remote user is not the super-user; in that

case the default is rsyncd.conf in the current directory (typi-

cally $HOME).

--no-detach

When running as a daemon, this option instructs rsync to not

detach itself and become a background process. This option is

required when running as a service on Cygwin, and may also be

useful when rsync is supervised by a program such as daemontools

or AIX's System Resource Controller. --no-detach is also recom-

mended when rsync is run under a debugger. This option has no

effect if rsync is run from inetd or sshd.

--port=PORT

This specifies an alternate TCP port number for the daemon to

listen on rather than the default of 873. See also the "port"

global option in the rsyncd.conf manpage.

--log-file=FILE

This option tells the rsync daemon to use the given log-file

name instead of using the "log file" setting in the config file.

--log-file-format=FORMAT

This option tells the rsync daemon to use the given FORMAT

string instead of using the "log format" setting in the config

file. It also enables "transfer logging" unless the string is

empty, in which case transfer logging is turned off.

--sockopts

This overrides the socket options setting in the rsyncd.conf

file and has the same syntax.

-v, --verbose

This option increases the amount of information the daemon logs

during its startup phase. After the client connects, the dae-

mon's verbosity level will be controlled by the options that the

client used and the "max verbosity" setting in the module's con-

fig section.

-4, --ipv4 or -6, --ipv6

Tells rsync to prefer IPv4/IPv6 when creating the incoming sock-

ets that the rsync daemon will use to listen for connections.

One of these options may be required in older versions of Linux

to work around an IPv6 bug in the kernel (if you see an "address

already in use" error when nothing else is using the port, try

specifying --ipv6 or --ipv4 when starting the daemon).

-h, --help

When specified after --daemon, print a short help page describ-

ing the options available for starting an rsync daemon.

FILTER RULES

The filter rules allow for flexible selection of which files to trans-

fer (include) and which files to skip (exclude). The rules either

directly specify include/exclude patterns or they specify a way to

acquire more include/exclude patterns (e.g. to read them from a file).

As the list of files/directories to transfer is built, rsync checks

each name to be transferred against the list of include/exclude pat-

terns in turn, and the first matching pattern is acted on: if it is an

exclude pattern, then that file is skipped; if it is an include pattern

then that filename is not skipped; if no matching pattern is found,

then the filename is not skipped.

Rsync builds an ordered list of filter rules as specified on the com-

mand-line. Filter rules have the following syntax:

RULE [PATTERN_OR_FILENAME]

RULE,MODIFIERS [PATTERN_OR_FILENAME]

You have your choice of using either short or long RULE names, as

described below. If you use a short-named rule, the ',' separating the

RULE from the MODIFIERS is optional. The PATTERN or FILENAME that fol-

lows (when present) must come after either a single space or an under-

score (_). Here are the available rule prefixes:

exclude, - specifies an exclude pattern.

include, + specifies an include pattern.

merge, . specifies a merge-file to read for more rules.

dir-merge, : specifies a per-directory merge-file.

hide, H specifies a pattern for hiding files from the transfer.

show, S files that match the pattern are not hidden.

protect, P specifies a pattern for protecting files from dele-

tion.

risk, R files that match the pattern are not protected.

clear, ! clears the current include/exclude list (takes no arg)

When rules are being read from a file, empty lines are ignored, as are

comment lines that start with a "#".

Note that the --include/--exclude command-line options do not allow the

full range of rule parsing as described above -- they only allow the

specification of include/exclude patterns plus a "!" token to clear the

list (and the normal comment parsing when rules are read from a file).

If a pattern does not begin with "- " (dash, space) or "+ " (plus,

space), then the rule will be interpreted as if "+ " (for an include

option) or "- " (for an exclude option) were prefixed to the string. A

--filter option, on the other hand, must always contain either a short

or long rule name at the start of the rule.

Note also that the --filter, --include, and --exclude options take one

rule/pattern each. To add multiple ones, you can repeat the options on

the command-line, use the merge-file syntax of the --filter option, or

the --include-from/--exclude-from options.

INCLUDE/EXCLUDE PATTERN RULES

You can include and exclude files by specifying patterns using the "+",

"-", etc. filter rules (as introduced in the FILTER RULES section

above). The include/exclude rules each specify a pattern that is

matched against the names of the files that are going to be trans-

ferred. These patterns can take several forms:

o if the pattern starts with a / then it is anchored to a particu-

lar spot in the hierarchy of files, otherwise it is matched

against the end of the pathname. This is similar to a leading ^

in regular expressions. Thus "/foo" would match a file named

"foo" at either the "root of the transfer" (for a global rule)

or in the merge-file's directory (for a per-directory rule). An

unqualified "foo" would match any file or directory named "foo"

anywhere in the tree because the algorithm is applied recur-

sively from the top down; it behaves as if each path component

gets a turn at being the end of the file name. Even the unan-

chored "sub/foo" would match at any point in the hierarchy where

a "foo" was found within a directory named "sub". See the sec-

tion on ANCHORING INCLUDE/EXCLUDE PATTERNS for a full discussion

of how to specify a pattern that matches at the root of the

transfer.

o if the pattern ends with a / then it will only match a direc-

tory, not a file, link, or device.

o rsync chooses between doing a simple string match and wildcard

matching by checking if the pattern contains one of these three

wildcard characters: '*', '?', and '[' .

o a '*' matches any non-empty path component (it stops at

slashes).

o use '**' to match anything, including slashes.

o a '?' matches any character except a slash (/).

o a '[' introduces a character class, such as [a-z] or

[[:alpha:]].

o in a wildcard pattern, a backslash can be used to escape a wild-

card character, but it is matched literally when no wildcards

are present.

o if the pattern contains a / (not counting a trailing /) or a

"**", then it is matched against the full pathname, including

any leading directories. If the pattern doesn't contain a / or a

"**", then it is matched only against the final component of the

filename. (Remember that the algorithm is applied recursively

so "full filename" can actually be any portion of a path from

the starting directory on down.)

o a trailing "dir_name/***" will match both the directory (as if

"dir_name/" had been specified) and all the files in the direc-

tory (as if "dir_name/**" had been specified). (This behavior

is new for version 2.6.7.)

Note that, when using the --recursive (-r) option (which is implied by

-a), every subcomponent of every path is visited from the top down, so

include/exclude patterns get applied recursively to each subcomponent's

full name (e.g. to include "/foo/bar/baz" the subcomponents "/foo" and

"/foo/bar" must not be excluded). The exclude patterns actually short-

circuit the directory traversal stage when rsync finds the files to

send. If a pattern excludes a particular parent directory, it can ren-

der a deeper include pattern ineffectual because rsync did not descend

through that excluded section of the hierarchy. This is particularly

important when using a trailing '*' rule. For instance, this won't

work:

+ /some/path/this-file-will-not-be-found

+ /file-is-included

- *

This fails because the parent directory "some" is excluded by the '*'

rule, so rsync never visits any of the files in the "some" or

"some/path" directories. One solution is to ask for all directories in

the hierarchy to be included by using a single rule: "+ */" (put it

somewhere before the "- *" rule), and perhaps use the

--prune-empty-dirs option. Another solution is to add specific include

rules for all the parent dirs that need to be visited. For instance,

this set of rules works fine:

+ /some/

+ /some/path/

+ /some/path/this-file-is-found

+ /file-also-included

- *

Here are some examples of exclude/include matching:

o "- *.o" would exclude all filenames matching *.o

o "- /foo" would exclude a file (or directory) named foo in the

transfer-root directory

o "- foo/" would exclude any directory named foo

o "- /foo/*/bar" would exclude any file named bar which is at two

levels below a directory named foo in the transfer-root direc-

tory

o "- /foo/**/bar" would exclude any file named bar two or more

levels below a directory named foo in the transfer-root direc-

tory

o The combination of "+ */", "+ *.c", and "- *" would include all

directories and C source files but nothing else (see also the

--prune-empty-dirs option)

o The combination of "+ foo/", "+ foo/bar.c", and "- *" would

include only the foo directory and foo/bar.c (the foo directory

must be explicitly included or it would be excluded by the "*")

MERGE-FILE FILTER RULES

You can merge whole files into your filter rules by specifying either a

merge (.) or a dir-merge (:) filter rule (as introduced in the FILTER

RULES section above).

There are two kinds of merged files -- single-instance ('.') and per-

directory (':'). A single-instance merge file is read one time, and

its rules are incorporated into the filter list in the place of the "."

rule. For per-directory merge files, rsync will scan every directory

that it traverses for the named file, merging its contents when the

file exists into the current list of inherited rules. These per-direc-

tory rule files must be created on the sending side because it is the

sending side that is being scanned for the available files to transfer.

These rule files may also need to be transferred to the receiving side

if you want them to affect what files don't get deleted (see PER-DIREC-

TORY RULES AND DELETE below).

Some examples:

merge /etc/rsync/default.rules

. /etc/rsync/default.rules

dir-merge .per-dir-filter

dir-merge,n- .non-inherited-per-dir-excludes

:n- .non-inherited-per-dir-excludes

The following modifiers are accepted after a merge or dir-merge rule:

o A - specifies that the file should consist of only exclude pat-

terns, with no other rule-parsing except for in-file comments.

o A + specifies that the file should consist of only include pat-

terns, with no other rule-parsing except for in-file comments.

o A C is a way to specify that the file should be read in a CVS-

compatible manner. This turns on 'n', 'w', and '-', but also

allows the list-clearing token (!) to be specified. If no file-

name is provided, ".cvsignore" is assumed.

o A e will exclude the merge-file name from the transfer; e.g.

"dir-merge,e .rules" is like "dir-merge .rules" and "- .rules".

o An n specifies that the rules are not inherited by subdirecto-

ries.

o A w specifies that the rules are word-split on whitespace

instead of the normal line-splitting. This also turns off com-

ments. Note: the space that separates the prefix from the rule

is treated specially, so "- foo + bar" is parsed as two rules

(assuming that prefix-parsing wasn't also disabled).

o You may also specify any of the modifiers for the "+" or "-"

rules (below) in order to have the rules that are read in from

the file default to having that modifier set. For instance,

"merge,-/ .excl" would treat the contents of .excl as absolute-

path excludes, while "dir-merge,s .filt" and ":sC" would each

make all their per-directory rules apply only on the sending

side.

The following modifiers are accepted after a "+" or "-":

o A "/" specifies that the include/exclude rule should be matched

against the absolute pathname of the current item. For example,

"-/ /etc/passwd" would exclude the passwd file any time the

transfer was sending files from the "/etc" directory, and "-/

subdir/foo" would always exclude "foo" when it is in a dir named

"subdir", even if "foo" is at the root of the current transfer.

o A "!" specifies that the include/exclude should take effect if

the pattern fails to match. For instance, "-! */" would exclude

all non-directories.

o A C is used to indicate that all the global CVS-exclude rules

should be inserted as excludes in place of the "-C". No arg

should follow.

o An s is used to indicate that the rule applies to the sending

side. When a rule affects the sending side, it prevents files

from being transferred. The default is for a rule to affect

both sides unless --delete-excluded was specified, in which case

default rules become sender-side only. See also the hide (H)

and show (S) rules, which are an alternate way to specify send-

ing-side includes/excludes.

o An r is used to indicate that the rule applies to the receiving

side. When a rule affects the receiving side, it prevents files

from being deleted. See the s modifier for more info. See also

the protect (P) and risk (R) rules, which are an alternate way

to specify receiver-side includes/excludes.

Per-directory rules are inherited in all subdirectories of the direc-

tory where the merge-file was found unless the 'n' modifier was used.

Each subdirectory's rules are prefixed to the inherited per-directory

rules from its parents, which gives the newest rules a higher priority

than the inherited rules. The entire set of dir-merge rules are

grouped together in the spot where the merge-file was specified, so it

is possible to override dir-merge rules via a rule that got specified

earlier in the list of global rules. When the list-clearing rule ("!")

is read from a per-directory file, it only clears the inherited rules

for the current merge file.

Another way to prevent a single rule from a dir-merge file from being

inherited is to anchor it with a leading slash. Anchored rules in a

per-directory merge-file are relative to the merge-file's directory, so

a pattern "/foo" would only match the file "foo" in the directory where

the dir-merge filter file was found.

Here's an example filter file which you'd specify via --filter=".

file":

merge /home/user/.global-filter

- *.gz

dir-merge .rules

+ *.[ch]

- *.o

This will merge the contents of the /home/user/.global-filter file at

the start of the list and also turns the ".rules" filename into a per-

directory filter file. All rules read in prior to the start of the

directory scan follow the global anchoring rules (i.e. a leading slash

matches at the root of the transfer).

If a per-directory merge-file is specified with a path that is a parent

directory of the first transfer directory, rsync will scan all the par-

ent dirs from that starting point to the transfer directory for the

indicated per-directory file. For instance, here is a common filter

(see -F):

--filter=': /.rsync-filter'

That rule tells rsync to scan for the file .rsync-filter in all direc-

tories from the root down through the parent directory of the transfer

prior to the start of the normal directory scan of the file in the

directories that are sent as a part of the transfer. (Note: for an

rsync daemon, the root is always the same as the module's "path".)

Some examples of this pre-scanning for per-directory files:

rsync -avF /src/path/ /dest/dir

rsync -av --filter=': ../../.rsync-filter' /src/path/ /dest/dir

rsync -av --filter=': .rsync-filter' /src/path/ /dest/dir

The first two commands above will look for ".rsync-filter" in "/" and

"/src" before the normal scan begins looking for the file in

"/src/path" and its subdirectories. The last command avoids the par-

ent-dir scan and only looks for the ".rsync-filter" files in each

directory that is a part of the transfer.

If you want to include the contents of a ".cvsignore" in your patterns,

you should use the rule ":C", which creates a dir-merge of the .cvsig-

nore file, but parsed in a CVS-compatible manner. You can use this to

affect where the --cvs-exclude (-C) option's inclusion of the per-

directory .cvsignore file gets placed into your rules by putting the

":C" wherever you like in your filter rules. Without this, rsync would

add the dir-merge rule for the .cvsignore file at the end of all your

other rules (giving it a lower priority than your command-line rules).

For example:

cat <<EOT | rsync -avC --filter='. -' a/ b

+ foo.o

:C

- *.old

EOT

rsync -avC --include=foo.o -f :C --exclude='*.old' a/ b

Both of the above rsync commands are identical. Each one will merge

all the per-directory .cvsignore rules in the middle of the list rather

than at the end. This allows their dir-specific rules to supersede the

rules that follow the :C instead of being subservient to all your

rules. To affect the other CVS exclude rules (i.e. the default list of

exclusions, the contents of HOME/.cvsignore, and the value of CVSIG-

NORE) you should omit the -C command-line option and instead insert a

"-C" rule into your filter rules; e.g. "--filter=-C".

LIST-CLEARING FILTER RULE

You can clear the current include/exclude list by using the "!" filter

rule (as introduced in the FILTER RULES section above). The "current"

list is either the global list of rules (if the rule is encountered

while parsing the filter options) or a set of per-directory rules

(which are inherited in their own sub-list, so a subdirectory can use

this to clear out the parent's rules).

ANCHORING INCLUDE/EXCLUDE PATTERNS

As mentioned earlier, global include/exclude patterns are anchored at

the "root of the transfer" (as opposed to per-directory patterns, which

are anchored at the merge-file's directory). If you think of the

transfer as a subtree of names that are being sent from sender to

receiver, the transfer-root is where the tree starts to be duplicated

in the destination directory. This root governs where patterns that

start with a / match.

Because the matching is relative to the transfer-root, changing the

trailing slash on a source path or changing your use of the --relative

option affects the path you need to use in your matching (in addition

to changing how much of the file tree is duplicated on the destination

host). The following examples demonstrate this.

Let's say that we want to match two source files, one with an absolute

path of "/home/me/foo/bar", and one with a path of "/home/you/bar/baz".

Here is how the various command choices differ for a 2-source transfer:

Example cmd: rsync -a /home/me /home/you /dest

+/- pattern: /me/foo/bar

+/- pattern: /you/bar/baz

Target file: /dest/me/foo/bar

Target file: /dest/you/bar/baz

Example cmd: rsync -a /home/me/ /home/you/ /dest

+/- pattern: /foo/bar (note missing "me")

+/- pattern: /bar/baz (note missing "you")

Target file: /dest/foo/bar

Target file: /dest/bar/baz

Example cmd: rsync -a --relative /home/me/ /home/you /dest

+/- pattern: /home/me/foo/bar (note full path)

+/- pattern: /home/you/bar/baz (ditto)

Target file: /dest/home/me/foo/bar

Target file: /dest/home/you/bar/baz

Example cmd: cd /home; rsync -a --relative me/foo you/ /dest

+/- pattern: /me/foo/bar (starts at specified path)

+/- pattern: /you/bar/baz (ditto)

Target file: /dest/me/foo/bar

Target file: /dest/you/bar/baz

The easiest way to see what name you should filter is to just look at

the output when using --verbose and put a / in front of the name (use

the --dry-run option if you're not yet ready to copy any files).

PER-DIRECTORY RULES AND DELETE

Without a delete option, per-directory rules are only relevant on the

sending side, so you can feel free to exclude the merge files them-

selves without affecting the transfer. To make this easy, the 'e' mod-

ifier adds this exclude for you, as seen in these two equivalent com-

mands:

rsync -av --filter=': .excl' --exclude=.excl host:src/dir /dest

rsync -av --filter=':e .excl' host:src/dir /dest

However, if you want to do a delete on the receiving side AND you want

some files to be excluded from being deleted, you'll need to be sure

that the receiving side knows what files to exclude. The easiest way

is to include the per-directory merge files in the transfer and use

--delete-after, because this ensures that the receiving side gets all

the same exclude rules as the sending side before it tries to delete

anything:

rsync -avF --delete-after host:src/dir /dest

However, if the merge files are not a part of the transfer, you'll need

to either specify some global exclude rules (i.e. specified on the com-

mand line), or you'll need to maintain your own per-directory merge

files on the receiving side. An example of the first is this (assume

that the remote .rules files exclude themselves):

rsync -av --filter=': .rules' --filter='. /my/extra.rules'

--delete host:src/dir /dest

In the above example the extra.rules file can affect both sides of the

transfer, but (on the sending side) the rules are subservient to the

rules merged from the .rules files because they were specified after

the per-directory merge rule.

In one final example, the remote side is excluding the .rsync-filter

files from the transfer, but we want to use our own .rsync-filter files

to control what gets deleted on the receiving side. To do this we must

specifically exclude the per-directory merge files (so that they don't

get deleted) and then put rules into the local files to control what

else should not get deleted. Like one of these commands:

rsync -av --filter=':e /.rsync-filter' --delete \

host:src/dir /dest

rsync -avFF --delete host:src/dir /dest

BATCH MODE

Batch mode can be used to apply the same set of updates to many identi-

cal systems. Suppose one has a tree which is replicated on a number of

hosts. Now suppose some changes have been made to this source tree and

those changes need to be propagated to the other hosts. In order to do

this using batch mode, rsync is run with the write-batch option to

apply the changes made to the source tree to one of the destination

trees. The write-batch option causes the rsync client to store in a

"batch file" all the information needed to repeat this operation

against other, identical destination trees.

To apply the recorded changes to another destination tree, run rsync

with the read-batch option, specifying the name of the same batch file,

and the destination tree. Rsync updates the destination tree using the

information stored in the batch file.

For convenience, one additional file is creating when the write-batch

option is used. This file's name is created by appending ".sh" to the

batch filename. The .sh file contains a command-line suitable for

updating a destination tree using that batch file. It can be executed

using a Bourne (or Bourne-like) shell, optionally passing in an alter-

nate destination tree pathname which is then used instead of the origi-

nal path. This is useful when the destination tree path differs from

the original destination tree path.

Generating the batch file once saves having to perform the file status,

checksum, and data block generation more than once when updating multi-

ple destination trees. Multicast transport protocols can be used to

transfer the batch update files in parallel to many hosts at once,

instead of sending the same data to every host individually.

Examples:

$ rsync --write-batch=foo -a host:/source/dir/ /adest/dir/

$ scp foo* remote:

$ ssh remote ./foo.sh /bdest/dir/

$ rsync --write-batch=foo -a /source/dir/ /adest/dir/

$ ssh remote rsync --read-batch=- -a /bdest/dir/ <foo

In these examples, rsync is used to update /adest/dir/ from

/source/dir/ and the information to repeat this operation is stored in

"foo" and "foo.sh". The host "remote" is then updated with the batched

data going into the directory /bdest/dir. The differences between the

two examples reveals some of the flexibility you have in how you deal

with batches:

o The first example shows that the initial copy doesn't have to be

local -- you can push or pull data to/from a remote host using

either the remote-shell syntax or rsync daemon syntax, as

desired.

o The first example uses the created "foo.sh" file to get the

right rsync options when running the read-batch command on the

remote host.

o The second example reads the batch data via standard input so

that the batch file doesn't need to be copied to the remote

machine first. This example avoids the foo.sh script because it

needed to use a modified --read-batch option, but you could edit

the script file if you wished to make use of it (just be sure

that no other option is trying to use standard input, such as

the "--exclude-from=-" option).

Caveats:

The read-batch option expects the destination tree that it is updating

to be identical to the destination tree that was used to create the

batch update fileset. When a difference between the destination trees

is encountered the update might be discarded with a warning (if the

file appears to be up-to-date already) or the file-update may be

attempted and then, if the file fails to verify, the update discarded

with an error. This means that it should be safe to re-run a read-

batch operation if the command got interrupted. If you wish to force

the batched-update to always be attempted regardless of the file's size

and date, use the -I option (when reading the batch). If an error

occurs, the destination tree will probably be in a partially updated

state. In that case, rsync can be used in its regular (non-batch) mode

of operation to fix up the destination tree.

The rsync version used on all destinations must be at least as new as

the one used to generate the batch file. Rsync will die with an error

if the protocol version in the batch file is too new for the batch-

reading rsync to handle. See also the --protocol option for a way to

have the creating rsync generate a batch file that an older rsync can

understand. (Note that batch files changed format in version 2.6.3, so

mixing versions older than that with newer versions will not work.)

When reading a batch file, rsync will force the value of certain

options to match the data in the batch file if you didn't set them to

the same as the batch-writing command. Other options can (and should)

be changed. For instance --write-batch changes to --read-batch,

--files-from is dropped, and the --filter/--include/--exclude options

are not needed unless one of the --delete options is specified.

The code that creates the BATCH.sh file transforms any fil-

ter/include/exclude options into a single list that is appended as a

"here" document to the shell script file. An advanced user can use

this to modify the exclude list if a change in what gets deleted by

--delete is desired. A normal user can ignore this detail and just use

the shell script as an easy way to run the appropriate --read-batch

command for the batched data.

The original batch mode in rsync was based on "rsync+", but the latest

version uses a new implementation.

SYMBOLIC LINKS

Three basic behaviors are possible when rsync encounters a symbolic

link in the source directory.

By default, symbolic links are not transferred at all. A message

"skipping non-regular" file is emitted for any symlinks that exist.

If --links is specified, then symlinks are recreated with the same tar-

get on the destination. Note that --archive implies --links.

If --copy-links is specified, then symlinks are "collapsed" by copying

their referent, rather than the symlink.

rsync also distinguishes "safe" and "unsafe" symbolic links. An exam-

ple where this might be used is a web site mirror that wishes ensure

the rsync module they copy does not include symbolic links to

/etc/passwd in the public section of the site. Using

--copy-unsafe-links will cause any links to be copied as the file they

point to on the destination. Using --safe-links will cause unsafe

links to be omitted altogether. (Note that you must specify --links

for --safe-links to have any effect.)

Symbolic links are considered unsafe if they are absolute symlinks

(start with /), empty, or if they contain enough ".." components to

ascend from the directory being copied.

Here's a summary of how the symlink options are interpreted. The list

is in order of precedence, so if your combination of options isn't men-

tioned, use the first line that is a complete subset of your options:

--copy-links

Turn all symlinks into normal files (leaving no symlinks for any

other options to affect).

--links --copy-unsafe-links

Turn all unsafe symlinks into files and duplicate all safe sym-

links.

--copy-unsafe-links

Turn all unsafe symlinks into files, noisily skip all safe sym-

links.

--links --safe-links

Duplicate safe symlinks and skip unsafe ones.

--links

Duplicate all symlinks.

DIAGNOSTICS

rsync occasionally produces error messages that may seem a little cryp-

tic. The one that seems to cause the most confusion is "protocol ver-

sion mismatch -- is your shell clean?".

This message is usually caused by your startup scripts or remote shell

facility producing unwanted garbage on the stream that rsync is using

for its transport. The way to diagnose this problem is to run your

remote shell like this:

ssh remotehost /bin/true > out.dat

then look at out.dat. If everything is working correctly then out.dat

should be a zero length file. If you are getting the above error from

rsync then you will probably find that out.dat contains some text or

data. Look at the contents and try to work out what is producing it.

The most common cause is incorrectly configured shell startup scripts

(such as .cshrc or .profile) that contain output statements for non-

interactive logins.

If you are having trouble debugging filter patterns, then try specify-

ing the -vv option. At this level of verbosity rsync will show why

each individual file is included or excluded.

EXIT VALUES

0 Success

1 Syntax or usage error

2 Protocol incompatibility

3 Errors selecting input/output files, dirs

4 Requested action not supported: an attempt was made to manipu-

late 64-bit files on a platform that cannot support them; or an

option was specified that is supported by the client and not by

the server.

5 Error starting client-server protocol

6 Daemon unable to append to log-file

10 Error in socket I/O

11 Error in file I/O

12 Error in rsync protocol data stream

13 Errors with program diagnostics

14 Error in IPC code

20 Received SIGUSR1 or SIGINT

21 Some error returned by waitpid()

22 Error allocating core memory buffers

23 Partial transfer due to error

24 Partial transfer due to vanished source files

25 The --max-delete limit stopped deletions

30 Timeout in data send/receive

ENVIRONMENT VARIABLES

CVSIGNORE

The CVSIGNORE environment variable supplements any ignore pat-

terns in .cvsignore files. See the --cvs-exclude option for more

details.

RSYNC_RSH

The RSYNC_RSH environment variable allows you to override the

default shell used as the transport for rsync. Command line

options are permitted after the command name, just as in the -e

option.

RSYNC_PROXY

The RSYNC_PROXY environment variable allows you to redirect your

rsync client to use a web proxy when connecting to a rsync dae-

mon. You should set RSYNC_PROXY to a hostname:port pair.

RSYNC_PASSWORD

Setting RSYNC_PASSWORD to the required password allows you to

run authenticated rsync connections to an rsync daemon without

user intervention. Note that this does not supply a password to

a shell transport such as ssh.

USER or LOGNAME

The USER or LOGNAME environment variables are used to determine

the default username sent to an rsync daemon. If neither is

set, the username defaults to "nobody".

HOME The HOME environment variable is used to find the user's default

.cvsignore file.

FILES

/etc/rsyncd.conf or rsyncd.conf

SEE ALSO

rsyncd.conf(5) fcntl(2)

BUGS

times are transferred as *nix time_t values

When transferring to FAT filesystems rsync may re-sync unmodified

files. See the comments on the --modify-window option.

file permissions, devices, etc. are transferred as native numerical

values

see also the comments on the --delete option

Please report bugs! See the website at http://rsync.samba.org/

VERSION

This man page is current for version 2.6.9 of rsync.

INTERNAL OPTIONS

The options --server and --sender are used internally by rsync, and

should never be typed by a user under normal circumstances. Some

awareness of these options may be needed in certain scenarios, such as

when setting up a login that can only run an rsync command. For

instance, the support directory of the rsync distribution has an exam-

ple script named rrsync (for restricted rsync) that can be used with a

restricted ssh login.

CREDITS

rsync is distributed under the GNU public license. See the file COPY-

ING for details.

A WEB site is available at http://rsync.samba.org/. The site includes

an FAQ-O-Matic which may cover questions unanswered by this manual

page.

The primary ftp site for rsync is ftp://rsync.samba.org/pub/rsync.

We would be delighted to hear from you if you like this program.

This program uses the excellent zlib compression library written by

Jean-loup Gailly and Mark Adler.

THANKS

Thanks to Richard Brent, Brendan Mackay, Bill Waite, Stephen Rothwell

and David Bell for helpful suggestions, patches and testing of rsync.

I've probably missed some people, my apologies if I have.

Especial thanks also to: David Dykstra, Jos Backus, Sebastian Krahmer,

Martin Pool, Wayne Davison, J.W. Schultz.

AUTHOR

rsync was originally written by Andrew Tridgell and Paul Mackerras.

Many people have later contributed to it.

Mailing lists for support and development are available at

http://lists.samba.org

本文参与 腾讯云自媒体同步曝光计划,分享自作者个人站点/博客。
原始发表:2020-03-19 ,如有侵权请联系 cloudcommunity@tencent.com 删除

本文分享自 作者个人站点/博客 前往查看

如有侵权,请联系 cloudcommunity@tencent.com 删除。

本文参与 腾讯云自媒体同步曝光计划  ,欢迎热爱写作的你一起参与!

评论
登录后参与评论
0 条评论
热度
最新
推荐阅读
相关产品与服务
文件存储
文件存储(Cloud File Storage,CFS)为您提供安全可靠、可扩展的共享文件存储服务。文件存储可与腾讯云服务器、容器服务、批量计算等服务搭配使用,为多个计算节点提供容量和性能可弹性扩展的高性能共享存储。腾讯云文件存储的管理界面简单、易使用,可实现对现有应用的无缝集成;按实际用量付费,为您节约成本,简化 IT 运维工作。
领券
问题归档专栏文章快讯文章归档关键词归档开发者手册归档开发者手册 Section 归档