DUPLICITY(1) User Manuals DUPLICITY(1)NAMEduplicity - Encrypted backup using rsync algorithm
SYNOPSISduplicity [options] source_directory target_url
duplicity [options] source_url target_directory
duplicity full [options] source_directory target_url
duplicity incremental [options] source_directory target_url
duplicity restore [options] source_url target_directory
duplicity verify [options] source_url target_directory
duplicity collection-status [options] target_url
duplicity list-current-files [options] target_url
duplicity cleanup [options] [--force] target_url
duplicity remove-older-than time [options] [--force] target_url
duplicity remove-all-but-n-full count [options] [--force] target_url
duplicity remove-all-inc-of-but-n-full count [options] [--force] tar‐
get_url
DESCRIPTION
Duplicity incrementally backs up files and directory by encrypting tar-
format volumes with GnuPG and uploading them to a remote (or local)
file server. Currently local, ftp, sftp/scp, rsync, WebDAV, WebDAVs,
Google Docs, HSi and Amazon S3 backends are available. Because duplic‐
ity uses librsync, the incremental archives are space efficient and
only record the parts of files that have changed since the last backup.
Currently duplicity supports deleted files, full Unix permissions,
directories, symbolic links, fifos, etc., but not hard links.
If you are backing up the root directory /, remember to --exclude
/proc, or else duplicity will probably crash on the weird stuff in
there.
EXAMPLES
Here is an example of a backup, using scp to back up /home/me to
some_dir on the other.host machine:
duplicity /home/me scp://uid@other.host/some_dir
If the above is run repeatedly, the first will be a full backup, and
subsequent ones will be incremental. To force a full backup, use the
full action:
duplicity full /home/me scp://uid@other.host/some_dir
Now suppose we accidentally delete /home/me and want to restore it the
way it was at the time of last backup:
duplicity scp://uid@other.host/some_dir /home/me
Duplicity enters restore mode because the URL comes before the local
directory. If we wanted to restore just the file "Mail/article" in
/home/me as it was three days ago into /home/me/restored_file:
duplicity-t 3D --file-to-restore Mail/article
scp://uid@other.host/some_dir /home/me/restored_file
The following command compares the files we backed up, so see what has
changed since then:
duplicity verify scp://uid@other.host/some_dir /home/me
Finally, duplicity recognizes several include/exclude options. For
instance, the following will backup the root directory, but exclude
/mnt, /tmp, and /proc:
duplicity--exclude /mnt --exclude /tmp --exclude /proc /
file:///usr/local/backup
Note that in this case the destination is the local directory
/usr/local/backup. The following will backup only the /home and /etc
directories under root:
duplicity--include /home --include /etc --exclude '**' /
file:///usr/local/backup
Duplicity can also access a repository via ftp. If a user name is
given, the environment variable FTP_PASSWORD is read to determine the
password:
FTP_PASSWORD=mypassword duplicity /local/dir
ftp://user@other.host/some_dir
ACTIONS
cleanup
Delete the extraneous duplicity files on the given backend.
Non-duplicity files, or files in complete data sets will not be
deleted. This should only be necessary after a duplicity ses‐
sion fails or is aborted prematurely. Note that --force will be
needed to delete the files rather than just list them.
collection-status
Summarize the status of the backup repository by printing the
chains and sets found, and the number of volumes in each.
full Indicate full backup. If this is set, perform full backup even
if signatures are available.
incr If this is requested an incremental backup will be performed.
Duplicity will abort if old signatures cannot be found. The
default is to switch to full backup under these conditions.
list-current-files
Lists the files currently backed up in the archive. The infor‐
mation will be extracted from the signature files, not the ar‐
chive data itself. Thus the whole archive does not have to be
downloaded, but on the other hand if the archive has been
deleted or corrupted, this command may not detect it.
remove-older-than time
Delete all backup sets older than the given time. Old backup
sets will not be deleted if backup sets newer than time depend
on them. See the TIME FORMATS section for more information.
Note, this action cannot be combined with backup or other
actions, such as cleanup. Note also that --force will be needed
to delete the files rather than just list them.
remove-all-but-n-full count
Delete all backups sets that are older than the count:th last
full backup (in other words, keep the last count full backups
and associated incremental sets). count must be larger than
zero. A value of 1 means that only the single most recent backup
chain will be kept. Note that --force will be needed to delete
the files rather than just list them.
remove-all-inc-of-but-n-full count
Delete incremental sets of all backups sets that are older than
the count:th last full backup (in other words, keep only old
full backups and not their increments). count must be larger
than zero. A value of 1 means that only the single most recent
backup chain will be kept intact. Note that --force will be
needed to delete the files rather than just list them.
verify Enter verify mode instead of restore. If the --file-to-restore
option is given, restrict verify to that file or directory.
duplicity will exit with a non-zero error level if any files are
different. On verbosity level 4 or higher, log a message for
each file that has changed.
OPTIONS--allow-source-mismatch
Do not abort on attempts to use the same archive dir or remote
backend to back up different directories. duplicity will tell
you if you need this switch.
--archive-dir path
The archive directory. NOTE: This option changed in 0.6.0. The
archive directory is now necessary in order to manage persis‐
tence for current and future enhancements. As such, this option
is now used only to change the location of the archive direc‐
tory. The archive directory should not be deleted, or duplicity
will have to recreate it from the remote repository (which may
require decrypting the backup contents).
When backing up or restoring, this option specifies that the
local archive directory is to be created in path. If the ar‐
chive directory is not specified, the default will be to create
the archive directory in ~/.cache/duplicity/.
The archive directory can be shared between backups to multiple
targets, because a subdirectory of the archive dir is used for
individual backups (see --name ).
The combination of archive directory and backup name must be
unique in order to separate the data of different backups.
The interaction between the --archive-dir and the --name options
allows for four possible combinations for the location of the
archive dir:
1. neither specified (default)
~/.cache/duplicity/hash-of-url
2. --archive-dir=/arch, no --name
/arch/hash-of-url
3. no --archive-dir, --name=foo
~/.cache/duplicity/foo
4. --archive-dir=/arch, --name=foo
/arch/foo
--asynchronous-upload
(EXPERIMENTAL) Perform file uploads asynchronously in the back‐
ground, with respect to volume creation. This means that duplic‐
ity can upload a volume while, at the same time, preparing the
next volume for upload. The intended end-result is a faster
backup, because the local CPU and your bandwidth can be more
consistently utilized. Use of this option implies additional
need for disk space in the temporary storage location; rather
than needing to store only one volume at a time, enough storage
space is required to store two volumes.
--dry-run
Calculate what would be done, but do not perform any backend
actions
--encrypt-key key
When backing up, encrypt to the given public key, instead of
using symmetric (traditional) encryption. Can be specified mul‐
tiple times.
--encrypt-secret-keyring filename
This option can only be used with --encrypt-key, and changes the
path to the secret keyring for the encrypt key to filename This
keyring is not used when creating a backup. If not specified,
the default secret keyring is used which is usually located at
.gnupg/secring.gpg
--encrypt-sign-key key
Convenience parameter. Same as --encrypt-key key --sign-key key.
--exclude shell_pattern
Exclude the file or files matched by shell_pattern. If a direc‐
tory is matched, then files under that directory will also be
matched. See the FILE SELECTION section for more information.
--exclude-device-files
Exclude all device files. This can be useful for security/per‐
missions reasons or if rdiff-backup is not handling device files
correctly.
--exclude-filelist filename
Excludes the files listed in filename. See the FILE SELECTION
section for more information.
--exclude-filelist-stdin
Like --exclude-filelist, but the list of files will be read from
standard input. See the FILE SELECTION section for more infor‐
mation.
--exclude-globbing-filelist filename
Like --exclude-filelist but each line of the filelist will be
interpreted according to the same rules as --include and
--exclude.
--exclude-if-present filename
Exclude directories if filename is present. This option needs to
come before any other include or exclude options.
--exclude-other-filesystems
Exclude files on file systems (identified by device number)
other than the file system the root of the source directory is
on.
--exclude-regexp regexp
Exclude files matching the given regexp. Unlike the --exclude
option, this option does not match files in a directory it
matches. See the FILE SELECTION section for more information.
--extra-clean
When cleaning up, be more aggressive about saving space. For
example, this may delete signature files for old backup chains.
See the cleanup argument for more information.
--file-to-restore path
This option may be given in restore mode, causing only path to
be restored instead of the entire contents of the backup ar‐
chive. path should be given relative to the root of the direc‐
tory backed up.
--full-if-older-than time
Perform a full backup if an incremental backup is requested, but
the latest full backup in the collection is older than the given
time. See the TIME FORMATS section for more information.
--force
Proceed even if data loss might result. Duplicity will let the
user know when this option is required.
--ftp-passive
Use passive (PASV) data connections. The default is to use pas‐
sive, but to fallback to regular if the passive connection fails
or times out.
--ftp-regular
Use regular (PORT) data connections.
--gio Use the GIO backend and interpret any URLs as GIO would.
--ignore-errors
Try to ignore certain errors if they happen. This option is only
intended to allow the restoration of a backup in the face of
certain problems that would otherwise cause the backup to fail.
It is not ever recommended to use this option unless you have a
situation where you are trying to restore from backup and it is
failing because of an issue which you want duplicity to ignore.
Even then, depending on the issue, this option may not have an
effect.
Please note that while ignored errors will be logged, there will
be no summary at the end of the operation to tell you what was
ignored, if anything. If this is used for emergency restoration
of data, it is recommended that you run the backup in such a way
that you can revisit the backup log (look for lines containing
the string IGNORED_ERROR).
If you ever have to use this option for reasons that are not
understood or understood but not your own responsibility, please
contact duplicity maintainers. The need to use this option under
production circumstances would normally be considered a bug.
--imap-mailbox option
Allows you to specify a different mailbox. The default is
"INBOX". Other languages may require a different mailbox than
the default.
--gpg-options options
Allows you to pass options to gpg encryption. The options list
should be of the form "opt1=parm1 opt2=parm2" where the string
is quoted and the only spaces allowed are between options.
--include shell_pattern
Similar to --exclude but include matched files instead. Unlike
--exclude, this option will also match parent directories of
matched files (although not necessarily their contents). See
the FILE SELECTION section for more information.
--include-filelist filename
Like --exclude-filelist, but include the listed files instead.
See the FILE SELECTION section for more information.
--include-filelist-stdin
Like --include-filelist, but read the list of included files
from standard input.
--include-globbing-filelist filename
Like --include-filelist but each line of the filelist will be
interpreted according to the same rules as --include and
--exclude.
--include-regexp regexp
Include files matching the regular expression regexp. Only
files explicitly matched by regexp will be included by this
option. See the FILE SELECTION section for more information.
--log-fd number
Write specially-formatted versions of output messages to the
specified file descriptor. The format used is designed to be
easily consumable by other programs.
--log-file filename
Write specially-formatted versions of output messages to the
specified file. The format used is designed to be easily con‐
sumable by other programs.
--name symbolicname
Set the symbolic name of the backup being operated on. The
intent is to use a separate name for each logically distinct
backup. For example, someone may use "home_daily_s3" for the
daily backup of a home directory to Amazon S3. The structure of
the name is up to the user, it is only important that the names
be distinct. The symbolic name is currently only used to affect
the expansion of --archive-dir , but may be used for additional
features in the future. Users running more than one distinct
backup are encouraged to use this option.
If not specified, the default value is a hash of the backend
URL.
--no-encryption
Do not use GnuPG to encrypt files on remote system. Instead
just write gzipped volumes.
--no-print-statistics
By default duplicity will print statistics about the current
session after a successful backup. This switch disables that
behavior.
--null-separator
Use nulls (\0) instead of newlines (\n) as line separators,
which may help when dealing with filenames containing newlines.
This affects the expected format of the files specified by the
--{include|exclude}-filelist[-stdin] switches as well as the
format of the directory statistics file.
--numeric-owner
On restore always use the numeric uid/gid from the archive and
not the archived user/group names, which is the default behav‐
iour. Recommended for restoring from live cds which might have
the users with identical names but different uids/gids.
--num-retries number
Number of retries to make on errors before giving up.
--old-filenames
Use the old filename format (incompatible with Windows/Samba)
rather than the new filename format.
--rename orig new
Treats the path orig in the backup as if it were the path new.
Can be passed multiple times. An example:
duplicity restore --rename Documents/metal Music/metal
scp://uid@other.host/some_dir /home/me
--rsync-options options
Allows you to pass options to the rsync backend. The options
list should be of the form "opt1=parm1 opt2=parm2" where the
option string is quoted and the only spaces allowed are between
options. The option string will be passed verbatim to rsync,
after any internally generated option designating the remote
port to use. Here is a possibly useful example:
duplicity --rsync-options="--partial-dir=.rsync-partial"
/home/me scp://uid@other.host/some_dir
--s3-european-buckets
When using the Amazon S3 backend, create buckets in Europe
instead of the default (requires --s3-use-new-style ). Also see
the EUROPEAN S3 BUCKETS section.
--s3-unencrypted-connection
Don't use SSL for connections to S3.
This may be much faster, at some cost to confidentiality.
With this option, anyone who can observe traffic between your
computer and S3 will be able to tell: that you are using Duplic‐
ity, the name of the bucket, your AWS Access Key ID, the incre‐
ment dates and the amount of data in each increment.
This option affects only the connection, not the GPG encryption
of the backup increment files. Unless that is disabled, an
observer will not be able to see the file names or contents.
--s3-use-new-style
When operating on Amazon S3 buckets, use new-style subdomain
bucket addressing. This is now the preferred method to access
Amazon S3, but is not backwards compatible if your bucket name
contains upper-case characters or other characters that are not
valid in a hostname.
--scp-command command
Deprecated and ignored. The sftp/scp backend does no longer use
an external scp client program.
--sftp-command command
Deprecated and ignored. The sftp/scp backend does no longer use
an external sftp client program.
--sign-key key
This option can be used when backing up, restoring or verifying.
When backing up, all backup files will be signed with keyid key.
When restoring, duplicity will signal an error if any remote
file is not signed with the given keyid. key should be an 8
character hex string, like AA0E73D2. Should be specified only
once because currently only one signing key is supported. Last
entry overrides all other entries.
see also A NOTE ON SYMMETRIC ENCRYPTION AND SIGNING
--ssh-askpass
Tells the sftp/scp backend to use FTP_PASSWORD from the environ‐
ment, or, if that is not present, to prompt the user for the
remote system password. This password is also used for ssh keys
that are passphrase-protected. Without this option the password
is expected in the url.
--ssh-options options
Allows you to pass options to the ssh/scp/sftp backend. The
options list should be of the form "-oopt1=parm1 -oopt2=parm2"
where the option string is quoted and the only spaces allowed
are between options. Options must be given in the long option
format described in ssh_config(5). The sftp/scp backend cur‐
rently supports only one ssh option, IdentityFile like in this
example:
duplicity --ssh-options="-oIdentityFile=/my/backup/id" /home/me
sftp://uid@other.host/some_dir
--short-filenames
If this option is specified, the names of the files duplicity
writes will be shorter (about 30 chars) but less understandable.
This may be useful when backing up to MacOS or another OS or FS
that doesn't support long filenames.
--tempdir directory
Use this existing directory for duplicity temporary files
instead of the system default, which is usually the /tmp direc‐
tory. This option supersedes any environment variable.
-ttime, --time time, --restore-time time
Specify the time from which to restore or list files.
--time-separator char
Use char as the time separator in filenames instead of colon
(":").
--timeout seconds
Use seconds as the socket timeout value if duplicity begins to
timeout during network operations. The default is 30 seconds.
--use-agent
If this option is specified, then --use-agent is passed to the
GnuPG encryption process and it will try to connect to gpg-agent
before it asks for a passphrase for --encrypt-key or --sign-key
if needed.
Note: GnuPG 2 and newer ignore this option and will always use a
running gpg-agent if no passphrase was delivered.
--use-scp
If this option is specified, then the sftp/scp backend will use
the scp protocol rather than sftp for backend operations. The
default is to use sftp, because it does not suffer from shell
quoting issues like scp.
--verbosity level, -vlevel
Specify output verbosity level (log level). Named levels and
corresponding values are 0 Error, 2 Warning, 4 Notice (default),
8 Info, 9 Debug (noisiest).
level may also be
a character: e, w, n, i, d
a word: error, warning, notice, info, debug
The options -v4, -vn and -vnotice are functionally equivalent,
as are the mixed/upper-case versions -vN, -vNotice and -vNOTICE.
--version
Print duplicity's version and quit.
--volsize number
Change the volume size to number Mb. Default is 25Mb.
ENVIRONMENT VARIABLES
TMPDIR, TEMP, TMP
In decreasing order of importance, specifies the directory to
use for temporary files (inherited from Python's tempfile mod‐
ule).
FTP_PASSWORD
Supported by most backends which are password capable. More
secure than setting it in the backend url (which might be read‐
able in the operating systems process listing to other users on
the same machine).
PASSPHRASE
This passphrase is passed to GnuPG. If this is not set, the user
will be prompted for the passphrase.
SIGN_PASSPHRASE
The passphrase to be used for --sign-key , if SIGN_PASSPHRASE is
not set but PASSPHRASE is set, the latter will be used. Other‐
wise, if no passphrase is available, the user will be prompted
for it.
URL FORMAT
Duplicity tries to maintain a standard URL format as much as possible.
The generic format for a URL is:
scheme://user[:password]@host[:port]/[/]path
It is not recommended to expose the password on the command line since
it could be revealed to anyone with permissions to do process listings,
however, it is permitted. Consider setting the environment variable
FTP_PASSWORD instead, which is supported by most, but not all backends.
Regardless of its name it can be used with other backends.
In protocols that support it, the path may be preceded by a single
slash, '/path', to represent a relative path to the target home direc‐
tory, or preceded by a double slash, '//path', to represent an absolute
filesystem path.
Formats of each of the URL schemes follow:
cf+http://container_name
file:///some_dir
ftp[s]://user[:password]@other.host[:port]/some_dir
hsi://user[:password]@other.host/some_dir
imap[s]://user[:password]@host.com[/from_address_prefix]
see also A NOTE ON IMAP
using rsync daemon
rsync://user[:password]@host.com[:port]::[/]module/some_dir
using rsync over ssh (only key auth)
rsync://user@host.com[:port]/relative_path
rsync://user@host.com[:port]//absolute_path
s3://host/bucket_name[/prefix]
s3+http://bucket_name[/prefix]
see also A NOTE ON EUROPEAN S3 BUCKETS
Ubuntu One
u1://host/volume_path
u1+http://volume_path
see also A NOTE ON UBUNTU ONE
scp://.. or ssh://.. are synonymous with
sftp://user[:password]@other.host[:port]/[/]some_dir
see also --use-scp
tahoe://alias/directory
webdav[s]://user[:password]@other.host/some_dir
gdocs://user[:password]@other.host/some_dir
TIME FORMATSduplicity uses time strings in two places. Firstly, many of the files
duplicity creates will have the time in their filenames in the w3 date‐
time format as described in a w3 note at http://www.w3.org/TR/NOTE-
datetime. Basically they look like "2001-07-15T04:09:38-07:00", which
means what it looks like. The "-07:00" section means the time zone is
7 hours behind UTC.
Secondly, the -t, --time, and --restore-time options take a time
string, which can be given in any of several formats:
1. the string "now" (refers to the current time)
2. a sequences of digits, like "123456890" (indicating the time in
seconds after the epoch)
3. A string like "2002-01-25T07:00:00+02:00" in datetime format
4. An interval, which is a number followed by one of the characters
s, m, h, D, W, M, or Y (indicating seconds, minutes, hours,
days, weeks, months, or years respectively), or a series of such
pairs. In this case the string refers to the time that preceded
the current time by the length of the interval. For instance,
"1h78m" indicates the time that was one hour and 78 minutes ago.
The calendar here is unsophisticated: a month is always 30 days,
a year is always 365 days, and a day is always 86400 seconds.
5. A date format of the form YYYY/MM/DD, YYYY-MM-DD, MM/DD/YYYY, or
MM-DD-YYYY, which indicates midnight on the day in question,
relative to the current time zone settings. For instance,
"2002/3/5", "03-05-2002", and "2002-3-05" all mean March 5th,
2002.
FILE SELECTIONduplicity accepts the same file selection options rdiff-backup does,
including --exclude, --exclude-filelist-stdin, etc.
When duplicity is run, it searches through the given source directory
and backs up all the files specified by the file selection system. The
file selection system comprises a number of file selection conditions,
which are set using one of the following command line options:
--exclude, --exclude-device-files, --exclude-filelist, --exclude-
filelist-stdin, --exclude-globbing-filelist, --exclude-regexp,
--include, --include-filelist, --include-filelist-stdin, --include-
globbing-filelist, and --include-regexp. Each file selection condition
either matches or doesn't match a given file. A given file is excluded
by the file selection system exactly when the first matching file
selection condition specifies that the file be excluded; otherwise the
file is included.
For instance,
duplicity--include /usr --exclude /usr /usr
scp://user@host/backup
is exactly the same as
duplicity /usr scp://user@host/backup
because the include and exclude directives match exactly the same
files, and the --include comes first, giving it precedence. Similarly,
duplicity--include /usr/local/bin --exclude /usr/local /usr
scp://user@host/backup
would backup the /usr/local/bin directory (and its contents), but not
/usr/local/doc.
The include, exclude, include-globbing-filelist, and exclude-globbing-
filelist options accept extended shell globbing patterns. These pat‐
terns can contain the special patterns *, **, ?, and [...]. As in a
normal shell, * can be expanded to any string of characters not con‐
taining "/", ? expands to any character except "/", and [...] expands
to a single character of those characters specified (ranges are accept‐
able). The new special pattern, **, expands to any string of charac‐
ters whether or not it contains "/". Furthermore, if the pattern
starts with "ignorecase:" (case insensitive), then this prefix will be
removed and any character in the string can be replaced with an upper-
or lowercase version of itself.
Remember that you may need to quote these characters when typing them
into a shell, so the shell does not interpret the globbing patterns
before duplicity sees them.
The --exclude pattern option matches a file iff:
1. pattern can be expanded into the file's filename, or
2. the file is inside a directory matched by the option.
Conversely, --include pattern matches a file iff:
1. pattern can be expanded into the file's filename,
2. the file is inside a directory matched by the option, or
3. the file is a directory which contains a file matched by the
option.
For example,
--exclude /usr/local
matches /usr/local, /usr/local/lib, and /usr/local/lib/netscape. It is
the same as --exclude /usr/local --exclude '/usr/local/**'.
--include /usr/local
specifies that /usr, /usr/local, /usr/local/lib, and
/usr/local/lib/netscape (but not /usr/doc) all be backed up. Thus you
don't have to worry about including parent directories to make sure
that included subdirectories have somewhere to go. Finally,
--include ignorecase:'/usr/[a-z0-9]foo/*/**.py'
would match a file like /usR/5fOO/hello/there/world.py. If it did
match anything, it would also match /usr. If there is no existing file
that the given pattern can be expanded into, the option will not match
/usr.
The --include-filelist, --exclude-filelist, --include-filelist-stdin,
and --exclude-filelist-stdin options also introduce file selection con‐
ditions. They direct duplicity to read in a file, each line of which
is a file specification, and to include or exclude the matching files.
Lines are separated by newlines or nulls, depending on whether the
--null-separator switch was given. Each line in a filelist is inter‐
preted similarly to the way extended shell patterns are, with a few
exceptions:
1. Globbing patterns like *, **, ?, and [...] are not expanded.
2. Include patterns do not match files in a directory that is
included. So /usr/local in an include file will not match
/usr/local/doc.
3. Lines starting with "+ " are interpreted as include directives,
even if found in a filelist referenced by --exclude-filelist.
Similarly, lines starting with "- " exclude files even if they
are found within an include filelist.
For example, if file "list.txt" contains the lines:
/usr/local
- /usr/local/doc
/usr/local/bin
+ /var
- /var
then "--include-filelist list.txt" would include /usr, /usr/local, and
/usr/local/bin. It would exclude /usr/local/doc,
/usr/local/doc/python, etc. It neither excludes nor includes
/usr/local/man, leaving the fate of this directory to the next specifi‐
cation condition. Finally, it is undefined what happens with /var. A
single file list should not contain conflicting file specifications.
The --include-globbing-filelist and --exclude-globbing-filelist options
also specify filelists, but each line in the filelist will be inter‐
preted as a globbing pattern the way --include and --exclude options
are interpreted (although "+ " and "- " prefixing is still allowed).
For instance, if the file "globbing-list.txt" contains the lines:
dir/foo
+ dir/bar
- **
Then "--include-globbing-filelist globbing-list.txt" would be exactly
the same as specifying "--include dir/foo --include dir/bar --exclude
**" on the command line.
Finally, the --include-regexp and --exclude-regexp allow files to be
included and excluded if their filenames match a python regular expres‐
sion. Regular expression syntax is too complicated to explain here,
but is covered in Python's library reference. Unlike the --include and
--exclude options, the regular expression options don't match files
containing or contained in matched files. So for instance
--include '[0-9]{7}(?!foo)'
matches any files whose full pathnames contain 7 consecutive digits
which aren't followed by 'foo'. However, it wouldn't match /home even
if /home/ben/1234567 existed.
A NOTE ON EUROPEAN S3 BUCKETS
Amazon S3 provides the ability to choose the location of a bucket upon
its creation. The purpose is to enable the user to choose a location
which is better located network topologically relative to the user,
because it may allow for faster data transfers.
duplicity will create a new bucket the first time a bucket access is
attempted. At this point, the bucket will be created in Europe if
--s3-european-buckets was given. For reasons having to do with how the
Amazon S3 service works, this also requires the use of the --s3-use-
new-style option. This option turns on subdomain based bucket address‐
ing in S3. The details are beyond the scope of this man page, but it is
important to know that your bucket must not contain upper case letters
or any other characters that are not valid parts of a hostname. Conse‐
quently, for reasons of backwards compatibility, use of subdomain based
bucket addressing is not enabled by default.
Note that you will need to use --s3-use-new-style for all operations on
European buckets; not just upon initial creation.
You only need to use --s3-european-buckets upon initial creation, but
you may may use it at all times for consistency.
Further note that when creating a new European bucket, it can take a
while before the bucket is fully accessible. At the time of this writ‐
ing it is unclear to what extent this is an expected feature of Amazon
S3, but in practice you may experience timeouts, socket errors or HTTP
errors when trying to upload files to your newly created bucket. Give
it a few minutes and the bucket should function normally.
A NOTE ON IMAP
An IMAP account can be used as a target for the upload. The userid may
be specified and the password will be requested.
The from_address_prefix may be specified (and probably should be). The
text will be used as the "From" address in the IMAP server. Then on a
restore (or list) command the from_address_prefix will distinguish
between different backups.
A NOTE ON UBUNTU ONE
Connecting to Ubuntu One requires that you be running duplicity inside
of an X session so that you can be prompted for your credentials if
necessary by the Ubuntu One session daemon.
See https://one.ubuntu.com/ for more information about Ubuntu One.
A NOTE ON SYMMETRIC ENCRYPTION AND SIGNING
Signing and symmetrically encrypt at the same time with the gpg binary
on the command line, as used within duplicity, is a specifically chal‐
lenging issue. Tests showed that the following combinations proved
working.
1. Setup gpg-agent properly. Use the option --use-agent and enter both
passphrases (symmetric and sign key) in the gpg-agent's dialog.
2. Use a PASSPHRASE for symmetric encryption of your choice but the
signing key has an empty passphrase.
3. The used PASSPHRASE for symmetric encryption and the passphrase of
the signing key are identical.
KNOWN ISSUES / BUGS
Hard links currently unsupported (they will be treated as non-linked
regular files).
Bad signatures will be treated as empty instead of logging appropriate
error message.
OPERATION AND DATA FORMATS
This section describes duplicity's basic operation and the format of
its data files. It should not necessary to read this section to use
duplicity.
The files used by duplicity to store backup data are tarfiles in GNU
tar format. They can be produced independently by rdiffdir(1). For
incremental backups, new files are saved normally in the tarfile. But
when a file changes, instead of storing a complete copy of the file,
only a diff is stored, as generated by rdiff(1). If a file is deleted,
a 0 length file is stored in the tar. It is possible to restore a
duplicity archive "manually" by using tar and then cp, rdiff, and rm as
necessary. These duplicity archives have the extension difftar.
Both full and incremental backup sets have the same format. In effect,
a full backup set is an incremental one generated from an empty signa‐
ture (see below). The files in full backup sets will start with
duplicity-full while the incremental sets start with duplicity-inc.
When restoring, duplicity applies patches in order, so deleting, for
instance, a full backup set may make related incremental backup sets
unusable.
In order to determine which files have been deleted, and to calculate
diffs for changed files, duplicity needs to process information about
previous sessions. It stores this information in the form of tarfiles
where each entry's data contains the signature (as produced by rdiff)
of the file instead of the file's contents. These signature sets have
the extension sigtar.
Signature files are not required to restore a backup set, but without
an up-to-date signature, duplicity cannot append an incremental backup
to an existing archive.
To save bandwidth, duplicity generates full signature sets and incre‐
mental signature sets. A full signature set is generated for each full
backup, and an incremental one for each incremental backup. These
start with duplicity-full-signatures and duplicity-new-signatures
respectively. These signatures will be stored both locally and
remotely. The remote signatures will be encrypted if encryption is
enabled. The local signatures will not be encrypted and stored in the
archive dir (see --archive-dir ).
AUTHOR
Original Author - Ben Escoto <bescoto@stanford.edu>
Current Maintainer - Kenneth Loafman <kenneth@loafman.com>
SEE ALSOrdiffdir(1), python(1), rdiff(1), rdiff-backup(1).
Version 0.6.18 February 29, 2012 DUPLICITY(1)
